|
Gold Member Username: Larry_rNaples, FL Post Number: 2163 Registered: Oct-04 | For you long-suffering audio-friends - as You know, I've replaced both tweeters in the B&W 705s - and frankly they sound a lot cleaner. BUT The L-hand one remains screechy on the very high notes, especially strings. SIGH. I switched the speaker outs L to R on the amp, and the screechy highs stayed with the same speaker. Then I e-mailed B&W and my friendly tech said to swap out the tweeters (again!) to see if the sound stayed with the L-hand speaker. IT DID. OK - B&W is off for the weekend, so I'm left wondering - could it be the CROSSOVER? I've read several places where they can deteriorate over time. . . ANY HELP WELCOME HERE - i'M GETTING A BIT DESPERATE. And spending too much money! Respectfully. . .LarryR |
|
Silver Member Username: HawkbillyNova Scotia Canada Post Number: 889 Registered: Jul-07 | Potentially. That speaker takes some wild impedance swings, and above 10khz slopes from 6 down to 4 ohms at 20khz. Is it possible that the amp is strained above its limits at higher volumes and is clipping into the speaker ? Overall though, JA @ Stereophile didn't note that they were particularly difficult to drive. But if the amp has an issue it could be the culprit. |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14725 Registered: May-04 | . You are surmising a very unlikely scenario, LR. A few crossover components can deteriorate over long periods of time, several decades but not several years. The prime candidates for replacement after many years of service would be capacitors. Inductors are simply coils of wire and their values do not swing even over many decades and they are all but immune from physical damage resulting from high input voltage. Resistors employed in passive speaker crossovers are typically meant to absorb higher wattage than those used in active electronic circuits. This means most resistors found in crossovers will be a ceramic type rated for possibly ten or more watts - more than sufficient for the actual wattage coming into the circuit. Once again ceramic resistors are good for a virtual eternity and it is very difficult to damage them without subjecting them to outright abuse. That leaves only capacitors as the likely suspect for any crossover problems and they are also rated at high wattage and not likely to go defective in a few years time. That's not to say there might not be a defective component in your speaker but that it is highly unlikely. Amplifiers are not frequency selective therefore swapping speaker leads would generally not lead to any conclusive evidence pertaining to a speaker. Pull both speakers out into the center of the room and place them immediately side by side. If possible, place the amplifier into a mono mode to ensure both speakers are seeing identical signals. While playing a selection that shows the discrepancy pan back and forth with the balance control. You are listening to a mostly classical and operatic selection of material. This places the strings in the left hand channel in almost every case. You have a room with obvious problems. If you even suspect the one speaker has a problem, swap the speakers themself side to side so the offending speaker is not playing those high frequency instruments and is not residing in a location which might acerbate the problem. Those two tests should give you a better idea of where the problem resides. I assume Mer hears the same problems you do. . |
|
Gold Member Username: Mike3Wylie, Tx USA Post Number: 2365 Registered: May-06 | What about measuring the voltage at the input to the tweeters using a demo CD, ideally running a constant tone in mono? Assuming speaker swaps have proven that the problem follows the speaker. |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14728 Registered: May-04 | . If the problem follows the speaker, the service tech will know what tests to run to satisfy B&W's warranty. The shop will have better equipment for such purposes than a test CD. . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2164 Registered: Oct-04 | Thanx, all. Here's what I've done today. 1 - ran the Oppo-provided tone testing disc many times. In each case, with the speakers side by side, the L-hand one got a distorted sound above what I am guessing is about 5,000 Hz. Although the tone CD did not use violins, there was some screech in the left speaker every time. 2 - Traded amp-out connections, realizing, as Jan so rightly said, that the strings are nearly always on the L-hand side. When the R-hand speaker was playing the L channel (with high strings) the screech was gone on that side, but resided still in the L-hand speaker. 3 - Switched the tweeters. This did not make any sonic difference - the screech remained on the L-hand speaker. 4 - I have no way of doing voltage testing. . .SIGH. 5 -Did the Vigne Swing - or, set speakers out and did the monaural balance shifting. The L-hand speaker still has screech in the highs, whilst the R-hand one is much "warmer" and neutral-sounding. Both tweeters are brand new from B&W - even with a "tested" sticker on them! (whooppee - that means, uh. . . .) OK - I'm out of tests - the B&W tech will surely get back to me on Monday. Meanwhile, I hate to take the speakers into the local shop - they charge $75 take-in fee, plus whatever else might be needed. SIGH. But it may come to that. . . Respectfully. . .LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2165 Registered: Oct-04 | Sorry - Chris H - I see no way that the amp is clipping. It's a 100-watt-ch NAD 763, and I'm only running the volume up to "average" listening levels - not really high volume at all. Plus, I'm listening to small orchestra or chamber groups - not Rock or Jazz. But I'm open to all comments! Respectfully. . .LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2166 Registered: Oct-04 | Jan - I keep forgetting stuff. You may remember that when the NAD was going bad it gave off loud buzzing noises that Mer heard, but I did not. Until the one night when there was this terrific BANG coming from the living room - and the NAD was dead. Bad solder joint on the "anode" was the way it was explained to me. The B&W tech said there could well have been a momentary voltage surge at that point. Don't know. But it was after that event that the speaker got so "screechy" that I noticed it immediately. That "might" have done in either a tweeter or crossover? Asking, 'cause I haven't the foggiest idea. I'm a music guy, not an electronics guy. SIGH. Respectfully. . .LarryR |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14730 Registered: May-04 | . There's no way to tell, Larry, even if they decide a cap or the driver has gone "all mavericky on ya". Caps (the most logical component to fail) in speakers normally can handle some fairly high voltages for a reasonable amount of time. Buzzes and bangs tend not to be high frequency in nature so I wouldn't expect that to be causational. You just never know unless there is an obvious conclusion to be drawn such as a cap has just overstayed its welcome by a dozen years. Customers typically wanted a reason for a failure and, like a cause of death in an 88 year old, the best answer oftentimes was, "It stopped working". Parts fail no matter the pedigree of the company, that's why all manufacturers of any decent quality have tech support. Sometimes the best answer is just that the manufacturer can't predict, after throwing the switch 500k times on the test bench, that it won't fail on the 500,005th time. Nothing the user could do would have prevented it. If the tweeter or crossover is defective, B&W should repair the unit and you might as well just listen to your music and not give it another thought. I'm sure should they determine there is something you have done to cause the problem, they will inform you of your error and how to prevent its reocurrence. As is, it doesn't sound like anything you could have prevented or predicted. . . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2167 Registered: Oct-04 | Well, Jan - the B&W guy should get back to me on Monday. And then I may or may not take into our local shop again - where I really don't trust their expertise, but it's the only game in town. I'm just getting way, way too frustrated, and that's not good. thanks for all your comments, however. I do appreciate. . . Respectfully. . .LarryR |
|
Gold Member Username: My_rantzGold CoastAustralia Post Number: 3092 Registered: Nov-05 | Larry any news from B&W? Have you tried the above suggestions using the dedicated 2 channel analogue outputs from the Oppo? Just to test the dacs - as you know they use 2 sets of quad dacs for the dedicated stereo outputs. This will just test that the multi channel dac isn't the problem. Providing of course that dac's can cause such a problem - as a certain someone on this forum will happily tell you, I wouldn't have a clue. |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2168 Registered: Oct-04 | G-day, all - the very cooperative and knowledgeable tech with B&W DID indeed give me an e-shout minutes ago. He had me download the 705 tech sheet - and then told me to take apart the "offending" speaker. The crossover is attached to the backplate where the speaker wires enter. After I get the plate off and disconnect the wires to tweeter and woofer he'll "lead me through" testing with my volt/ohm meter. Which I can barely understand, but will give it my all. Will let you know the results - in about six hours. SIGH. Respectfully. . .LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2169 Registered: Oct-04 | I think I've got in way over my head. The B&W tech never hinted at how difficult "just taking off the back plate and crossover" would be. The four wires are soldered to the plate, so I had to dig into the speaker and dig out about a half-ton of white fuzzy stuff (hope I eventually get it stuffed back in the right place!) and then un-plug the spade connectors on woofer and tweeter. Easier said. . .had to remove the upper tweeter housing, un-do the connectors, then clean out a huge gob of black horrible sticky gunk. SIGH. Then one of the spades on the woofer wouldn't let go, and it was a tussle! I'll never get those back on!!! So now the crossover sits on my desk, wires protruding, waiting for Eric at B&W to put me through whatever paces. Maybe after this I'll sell everything and get an iPod with Bose speakers and be happy???? Respectfully. . . .LarryR |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14731 Registered: May-04 | . " ... had to remove the upper tweeter housing, un-do the connectors, then clean out a huge gob of black horrible sticky gunk." You might want to ask the tech about this "gunk". Depending on where it was when you encountered it, it might be the ferro-fluid damping from the driver's voice coil. That would explain the less than great sound. If this is the case, it would place the gunk somewhere around the connection between the driver assembly and the front mounting plate in most cases though it shouldn't appear to be a material used to seal the driver's frame to the baffle. There is typically less than a teaspoonful of this fluid in a driver, so judge for yourself what you might have encountered but it would be worth asking. I'm rather surprised the tech suggested you do this yourself. Speaker disassembly and re-assssembly can get rather tedious and somewhat similar to taking a door panel off your car. You might get it off but getting back together is another story. Do be careful with the push on connectors. It's very easy to bend a terminal and then you could find yourself with more problems. The white fluffy stuff is (hopefully) polyfill or a similar material as not many speaker manufacturers use fiberglass at this time. You'll want to ask about any specific instructions on replacing the material in the cabinet to ensure proper damping. For the most part enclosures just get stuffed in no particular order but every now and then a designer wants a particular method used to ensure the repair coincides with the original design. Of all the things to consider here, a defective converter would have even lower odds of being the cause of your problem than would a polar bear wearing a bowler hat and spats showing up at your house with fresh mangoes and a new B&W driver. Not entirely impossible but best not to wait for it to happen. Has the problem just started with the introduction of the Oppo? . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2170 Registered: Oct-04 | Good comments, with thanks, Jan. First, the problem was there before the Oppo's introduction. Second, the black gunk is some sort of tar that is used to seal up the hole in the cabinet where the tweeter wires emerge. Too bad they didn't use a blu-tak type of stuff - the black gunk gets stuck on everything - had to use mineral spirits to get it off wires = and me! GRIN I put the ohm meter on the caps and resistors, and sent the info to B&W by e-mail. We'll see what they say, but it would appear that everything works. I hope I did the caps right - shorted them out, then put on the leads to watch the numbers climb - then the meter went back to "OL" which I guess is OK? The tech - or you - may answer that. The wadding isn't (apparentl) fiberglass - and as to jamming it back into place - well, I wish myself luck! And yes, I must be doubly careful with the spade connectors - especially on the woofer, where it's almost impossible to reach. SIGH. Wish me luck - but it looks like you were right - it's not the crossover. I've tried everything that you and all others have urged - but to no avail. I do know a guy who has dynamite, however. . . . .GRIN (??) Respectfully. . .LarryR |
|
Silver Member Username: MagfanUSA Post Number: 996 Registered: Oct-07 | for fine electronics I'm not in love with the 'short the cap and watch it charge' test. And given typical capacitor tolerance, 10% typical and UP, I don't know if comparing the 'good' to 'bad' side would give you any usable info. Does B&W use 5% caps? Any 'bulging' ends on the tubular caps? |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14732 Registered: May-04 | . "I hope I did the caps right - shorted them out, then put on the leads to watch the numbers climb - then the meter went back to "OL" which I guess is OK? The tech - or you - may answer that." Depends on what the tech suggested. Normally, it would be best to test a capacitor out of circuit as other components can affect the meter's readings. However, with a simple device such as a crossover, the tech must be certain nothing is in line to give false measurements. "OL" is what you should finally arrive at when measuring caps with a simple DVOM. This, of course, only indicates whether the cap has opened internally and not whether it has changed value. The logic here, I suspect, would be it is highly unlikely the cap has changed value by any significant amount in such a short time span. As Leo suggests you could disassemble the "good" speaker and compare measurements but IMO that would be low on my priority list considering the difficulties involved in the first go'round. A visual examination for any brown substance at the leads of the cap or bulging enclosures is about the best you can usually do after the DVOM shows the cap to be in operating condition. Good luck, Lar, I know it's frustrating to hunt down gremlins. The good news is you don't appear to be in any danger from spats wearing polar bears bearing dangerous mangoes. . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2171 Registered: Oct-04 | My pay grade ends way under your level, Jan! GRIN The test was done in accordance with B&W standard bench test, I guess - as I have no more esoteric instruments. 10% 5% - sorry - I don't know. The caps, BTW are rectangular 4.7uF and 10.0uF 100V MEBs, if that means anything more to you than it does to me. SIGH. Still waiting for B&Ws answer to my readings - then it will be "stuff and prod" for the next several hours as I try to get six quarts back into a two-quart enclosure. Oh, yes, Mer did resolve one of my truly angering problems - getting the connectors on the nearly-hidden tabs - she brought out a fine pair of locking forceps! Lock them onto the stub of the spade connector and the hunt-n-peck is greatly reduced. Can reach way beyond where my hands can easily go. GRIN Respectfully. . .LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2172 Registered: Oct-04 | Yeah, Jan - nothing in line - that's why he insisted that I remove the crossover from the speakers, I guess. Heck, I only do what I'm told here, as this is one area where I get so nervous the bathroom calls quite often. GRIN (?) So I wait for the final word from B&W - then where do I go? Crazy, I guess. I have nothing left to test. If it's the Oppo the sibilance and fuzziness would have changed speakers when I switched outputs. And the NAD would surely have distortion all up and down the spectrum if that was the problem - and unless the shop did a sloppy job, they tested it out "clean and clear" (they claim) when they re-did the solder joint. I just don't understand it. The offending speaker always sounds as though the treble is boosted and the upper freqs have a "sizzle" to them, especially on stringed instruments. The crossover on the 705s is 3700Hz - rather high, I know. I'm open to ANY answers! SIGH Respectfuly. . .LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2173 Registered: Oct-04 | The final blow has been struck. Eric, at B&W, says all the readings look good, so I'm left right back where I started. I finally got all the stuffings back in the speaker cabinet - but if I hadn't had a Mer-supplied pair of locking forceps I would NEVER have gotten the woofer connectors on. What a challenge! Well - I guess that about wraps up this thread. I'll go on and do some more testing, but I really don't have anyplace to go! Maybe an iPod and some earphones? Respectfully. . .Larry the Frustrated Silver Lounge Lizard. |
|
Silver Member Username: MagfanUSA Post Number: 997 Registered: Oct-07 | Cap Test is done with the resistance scale. The meter puts a small current thru the device under test to determine resistance......voltage drop method? With a cap, it'll go to OL when the cap is charged and there is no longer any current flow.....like an open resistor. If caps are in parallel and one is fused open, the test may still give a 'good' indication since the bad cap is like...not in the circuit. When the probes are applied, the value should rise in steps over a few seconds. The 10mfd should take longer than the 4.7mfd to charge and reach OL. The perfect cap test using a DVM is, as Jan implied, with one leg of the cap lifted. The Perfecter test would be to use a capacitance meter to actually measure the value of the cap. In your case 4.7mfd or 10mfd....the mfd being Micro Farad...a unit of measure. Have you tried the speaker since reassembly? Wacky small chance the problem was an oxidized / loose connection....didn't think so! I hope you put the connectors back where they came from. An out of phase condition will drive you nuts after the original problem gets resolved. I still think you've got a bad cap. It happens, even in new electronics. |
|
Silver Member Username: EzntnGreeneville, TN Post Number: 178 Registered: Apr-09 | I finally got all the stuffings back in the speaker cabinet - but if I hadn't had a Mer-supplied pair of locking forceps I would NEVER ...... hemostats LR .. used for enjoying that last small bit of ..... 'erbage now we know ... |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2174 Registered: Oct-04 | Hemostats - ah,yes - guess that's what they are. SIGH. Never used them to hold anything other than electronics,though. GRIN Ahem. . . Anyway, the B&W has two different sizes of woofer tabs, so there's no way to put the leads on wrong. And the tweeter wires and tabs are color-coded, red and black. Yes, I put the speakers back in service - but the problem remains. It's not so bad I can't live with it, but naggy, anyway. SIGH. Don't know where to turn next. Should I take the speaker into the shop and have them go through the crossover tests all over again? A lot of money they want - minimum of $175 - to test it. Frustration. . . I'm still wondering if it could be the NAD - but at this point I'm too tired out to care tonight. More thinking tomorrow. Thanks for all of your suggestions. . .truly. Respectfully. . .LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2175 Registered: Oct-04 | Forgot - one last question. What would the result be IF one capacitor is "bad?" I just don't know. LR |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14733 Registered: May-04 | . Call your friend in the studio and ask him about various methods to test for actual frequency deviation. If you have a SPL meter, you might possibly perform a very basic test yourself though, to be honest, the RS SPL meter isn't sophisticated enough to tell you much in this sort of test. You'll need to set the speakers up one by one in a spot at the same distance from the meter. Changing the location of the speakers or the location of the meter will negate any measurement deviations. Then you'll need a test tone with either a frequency sweep or steps at non-specific frequencies. If you have no test disc but you have the ability to use computer generated tones, place something on the order of "tone generator" or "frequency generator" in a search engine to find a freeware based product. You're going to have to prove there is a problem with the driver before you can procede. Having some sort of proof there is a frequency deviation between the two tweeters is the best way I can think to begin. Proving there is a "sizzle" is far more difficult unless you pay the tech to go over the speaker in the shop. Unfortunately, if you can't establish a deviation from normal in the tweeter on your own, your only recourse IMO is to allow the shop to go through the speaker - which still may turn up nothing. "What would the result be IF one capacitor is 'bad'?" Capacitors can be used to block either high or low frequencies depending on their application in a crossover. In this case it is fairly common to use a cap to block low frequencies from entering the tweeter (making it part of a "hi-pass" filter). In other words, if the value of the cap had drifted, it might lower the crossover point to the tweeter. Thing is, it would have to drift rather far to have any real effect on the performance of the driver (which is why the tech didn't have you measure for value just operation). The tolerances on the cap allow for a rather wide deviation from the factory spec to begin with. This sort of drift (allowing more energy into the tweeter below the normal 3700Hz filter) would place slightly too much energy in the upper range of, say, violins. http://www.psbspeakers.com/audio-topics/The-Frequencies-of-Music ("The offending speaker always sounds as though the treble is boosted and the upper freqs have a "sizzle" to them, especially on stringed instruments." That is an almost exact description of the sound of early digital recordings or digital recordings compressed to make them more palatable to the average listener.) If the cap had opened, there would be no sound from the driver in most instances. Or, depending on the crossover, it would allow much lower frequencies into the tweeter which would make for a very unhappy tweeter. That would be the only other option for a cap in most common crossovers. If the cap had drifted far enough to alter the value of the crossover, the slightly lower frequencies reaching the tweeter would have a very minimal chance of overdriving the tweeter if you were blasting away at the volume control. Otherwise, there isn't much a high pass filter capacitor might affect that I can think of. The component used to set relative levels betweens drivers in a speaker system is a resistor (normally placed in series with the driver). If the resistor measured its correct value - as indicated by the B&W tech, there isn't much chance the resistor has drifted either as this normally takes decades to occur and the tolerances on the resistors are pretty broad in most cases making values less than spot on to begin with. Raspy sounds are most commonly the fault of the driver itself. As I said, it's very difficult to damage the crossover components. The driver is far more delicate but you've not indicated anything that would suggest you've used the system in a way that would damage a tweeter. Have you ever played the system loud enough for the amplifier to clip for an extended time? This is what damages tweeters. If you haven't clipped the amp for a few minutes, then that would tend to rule out a damaged driver. Then the next option would be a defective driver was installed. This, however, would rule out a defective tweeter; "Then I e-mailed B&W and my friendly tech said to swap out the tweeters (again!) to see if the sound stayed with the L-hand speaker. IT DID." If it isn't the tweeter and it's not the crossover and changing speaker cabling side to side hasn't resolved the problem, there's nothing particular left that would have the effect you're describing, Larry. New speaker cabling might be your answer, try something like the 16 AWG Home Depot orange outdoor extension cord with the ends cut off (use two of the three conductors). It has a nice smooth sound and won't cost you an arm and a leg. Exactly when did you begin to notice this problem? What occurred just prior to you first noticing the problem? . |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14737 Registered: May-04 | . "This sort of drift (allowing more energy into the tweeter below the normal 3700Hz filter) would place slightly too much energy in the upper range of, say, violins." Just to be clear, this would affect the upper fundamentals of the violin in particular. With a harmonically rich instrument such as the violin I don't know that I would call this effect "sizzle". When I hear that term I think more towards a driver that is not operating as it should or one tipped up rather high in level. Cranking a treble control to the max could lean toward a "sizzley" high frequency content. Treble controls normally have their knee frequency positioned around 5kHz though some do place that point much lower in the range. To repeat, resistors in the crossover determine relative levels between drivers. . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2176 Registered: Oct-04 | You see? This is why I come on this Forum. Answers. Maybe more answers than there are questions, but welcome answers, anyway! GRIN OK - I don't have an SPL meter, but I did set the speakers side by side and run through the Oppo's frequency sweep disc - three times. As the disc sends the sounds to the mains channels alternately, I'm guessing that their levels are constant? In each case the "offending" speaker's high frequencies - those that the tweeter is supposed to produce - were slightly louder and had a bit of a ragged edge to them. Hard to exactly describe. I switched out the TWEETERS and the sound differences remained the same, so obviously it's not the tweeter's fault? I hope I'm answering your questions/comments, Jan. Speaker wire? Well, I'm using some rather new (6 mo. old) 10awg cable from Blue Jeans Cables. I also have a pair of their 12AWG cables, which I've alternately put into play - with no difference. Have not gone down to 16awg. . . As to when the problem became most noticeable - ummmm - I think it may always have been there, but perhaps I just noticed it more (?) after the NAD "blew up." The repair shop guy claimed that, when he re-did the cracked solder joint, he "swept" the whole amp and found it fine. I gotta trust him in this, though I'm willing to take the NAD in again for another check-up if there's any chance it might be the culprit. Frankly, to my (limited) way of thinking,the only plausible culprit here is the crossover - despite following the B&W tech's directions as to measurements and inspection. The caps,BTW, on the B&W crossover,are not cylinders,as you usually find, but rectangles soldered to the board. Never seen that before. They are not "bulging" or discolored at all. I tried to call Mark, out in LA, but was told that he's on vacation in New Zealand - won't be back until mid-April. (must be nice) As to running up the amp - not hardly no way. I may have on occasion run it fairly high, but never to the point where it might have any negative effect on the speakers. I never "blast" the system. Well - I may just take the speakers into the repair shop and ask them to play CDs with which I'm very familiar - see if the speakers sound different there - and if the tech there can detect the sort of distortion I claim - just by listening to them. If they sound much clearer there I'll know it's the amp - maybe. SIGH. I appreciate the extensive responses, and hope that all this frustration goes away soon! Respectfully. . .LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2177 Registered: Oct-04 | Crossed paths - yes, Jan - you've hit the nail right on the head. The speaker sounds as though I had the treble control on that one only set about 4-6db higher than on the other speaker. I think Art once described the sound as "glare." When a violin in a chamber group is playing - and I have the amp set on mono out - I turn from one speaker to the other - and the L-hand one always has higher, "sizzley" frequencies, whilst the other one is smoother and "warmer" (for lack of better word) sound. I have gone over every possible tone setting on the Oppo and the NAD, and ALL are set to FLAT position. When I do turn up the treble control, the L-hand speaker gets very, very Bright. I'm trying to give you good anwers - but maybe I'm failing. Respectfully. . .LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2178 Registered: Oct-04 | Let me now throw in a monkey wrench. Just a few minutes ago I thought I'd do another "what the heck" test - so I put on one of the worst-offending CDs. One that highlights high violin in a chamber group. It's a Hyperion recording, done in 2004 - some of my fav chamber music. But today I started the playback COLD. By that I mean I turned on the amp and Oppo, and hit "play." Now Hear This. At this very moment, both speakers are putting out fairly consistent - equal-sounding music. The L-hand one's highs are coming out only slightly more pronounced than the R-hand one, mainly because the L-hand channel has most of the violin music, whilst the R-hand one centers on the cello. OK - how come the speakers are sounding "better" when running COLD than they usually do. I ordinarily leave the kit on for at least ten minutes before playing anything. How's that for turkeys? GRIN I don't get it - Period. Respectfully. . .LarryR |
|
Silver Member Username: HawkbillyNova Scotia Canada Post Number: 891 Registered: Jul-07 | Faulty circuit boards will behave sometimes when they are cold, but go squirelly when they heat up. Were the xover components mounted on a circuit board ? When you did you testing were you testing only individual components, as opposed to the circuit ? Just to recap, the issue stays with the speaker enclosure, not the tweeter, correct ? When you switch terminals on the amp, the issue also stays with the enclosure, correct ? |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2179 Registered: Oct-04 | Chris - yes, the Xover components are mounted on a small circuit board that's bolted right to the back plate of the speaker. I tested the components on the board - which was not connected to anything at the time. The issue stays with the enclosure. I have, as you know, replaced Both tweeters from B&W, and the issue appears to always stay with the particular "box." I'd really like to hear these speakers with another AV receiver - I may take them into the dealer/shop tomorrow. . .or not. I'm getting too tired of all this frustration! GRIN Respectfully. . .LarryR PS - I'll post what's going on once the kit heats up - in a half hour or so. If the speakers get worse then I'll know that heat somewhere along the line is responsible? Or not. . . |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14738 Registered: May-04 | . It's very difficult to suggest where you head next when exchanging information over the forum. Without hearing the system a lot of this is merely guesswork about possibilities. Cold solder joints get reformed as they heat up and should they be opening up a bit, that could account for your "sizzely" sounds. If you assume the cold solder joint is opening up with heat, you would then assume the issue might be a cold solder joint at the resistor (which sets the level to the tweeter) since an opened joint would take the resistor out of circuit and allow for the higher level of the tweeter as more voltage flows. You would assume the signal would be at its best quality when the solder joint is cold and it would then worsen - making for a "sizzley" sound - as it heats up. If you assumed the tweeter was being somewhat overdriven by the higher voltage input as the solder joint opened - which is a very unlikely scenario IMO, then you might get to the point where you could reason the solder joint is raising level and making for worse sound as the joint is affected by heat. That would take a lot of assuming. Poor signal transfer in the warmed solder joint might get you where you need to go for this problem. That's still a lot of assuming IMO. One issue here is that both the receiver and the speaker have undergone repairs and either - or both - could be subject to poor solder connections. The problem does tend to stay with the speaker enclosure so you would lean towards the issue being restricted to the speaker and not involving the amp. Larry, if you have a medium wattage soldering iron around 30 watt range, you could remove the crossover one more time and retouch all the solder connections on the board. You shouldn't be in any danger of damaging the speaker in this manner, just heat the joints (place the tip of the iron directly on the lead out just above the circuit board) until they begin to soften and then allow them to reform without moving any wires or components. Without a soldering iron the best you could do would be to remove the crossover once again and under bright light and some magnification check for what would appear to be any cracks in the solder joints on either side of the crossover board. Otherwise, we're getting to the point where the repair shop is the only other option. . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2180 Registered: Oct-04 | Sorry to be away so long - but I had to go out grocery shopping. As poor Mer puts in 50-plus-hour work weeks, I do the shopping and cooking so I can hold my head up as "contributing something." SIGH. Jan - your points are all well-taken. I did examine the crossover under bright light, but not with magnification. I even wiggled the resistors and caps - very solid. Right now I'm of a mind to take the speakers in for a test drive at the shop, then if they say it's all in my head, I take in the NAD for another probing. This afternoon, when I came home, I'd left the NAD/Oppo on for more than 4 hours, and when I played several discs - the old bug-a-boo of high freq "splatter" was back. As it sometimes but not always does, the solo violin was now in the background, and distorted. All the lower tones were coming through in what I guess was normal level. I don't understand this at all. Maybe I'm just jinxed! GRIN I'd do more experimenting tomorrow, but have to take the Prius up to the shop - 25-th-mile servicing. Not bad for a car that'll be three years old in June. We'll make up for the low mileage later this year, however, when we drive out to (and, sigh, back from) Santa Fe. Until I get the speakers in the shop for their sound-appraisal, I've really got nothing more to add. Thanks SO MUCH for all the suggestions - and lessons! Respectfully. . .LarryR |
|
Silver Member Username: EzntnGreeneville, TN Post Number: 179 Registered: Apr-09 | Good luck in your audio quest LR, this has to be frustrating. To & from Santa Fe , from SW Fla? Talk about extremes in humidity ... you might need to join in on Nuck's road trip .. just to acclimate |
|
Silver Member Username: MagfanUSA Post Number: 1000 Registered: Oct-07 | Florida, eh? Now I know what happened. Some kind of power glitch. Florida has more thunder/lightning storms than almost anywhere. Almost certain than anywhere in the continental US. When I lived there we called FPL, Florida Power and LIght something more .... exact. We called 'em 'Florida Flicker and Flash' It is very impressive to be driving across the state from say....YeeHaw Junciton, West toward Tampa / St Pete, and see the whole sky light up with lightning as the evening storm comes ashore. Larry.... You been zapped. |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2181 Registered: Oct-04 | My friend, I've been zapped more times than you can count! GRIN I've got double layers of power surge protection on all my stuff, so I don't think that's the problem - I'm beginning to think it's all in my head! UH... No - I'm going to take the speakers into the shop for a listening-test, probably Thursday, and then go from there. There's a gremlin in my head that says "the crossover is the only possibility here" - but then for all I know it could be the output from the new Oppo. HIGHLY unlikely - but I may hook up the old 980 this ayem and give it a play - just to see. . . .OH, DOUBLE-SIGH. If what Jan has told me in past postings is correct - and I have no reason to doubt that - there is no way that the amp could be frequency-specific: either the whole spectrum is distorted or its not. OK - that would surely follow with the Oppo, wouldn't it? I mean, a DAC will either output good or bad signal - not some of it good, some of it bad? Right? So to my feeble mind, either the crossover is bad or I am simply not hearing ALL of the distortion in the L-hand channel. I've tried SO HARD to listen critically. . . Well - some coffee is needed. Respectfully. . .LarryR PS - thanks to ALL for the knowledge that I've gained here!! REally. . . |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14739 Registered: May-04 | . "If what Jan has told me in past postings is correct - and I have no reason to doubt that - there is no way that the amp could be frequency-specific: either the whole spectrum is distorted or its not." Amplifiers either tend to work or they don't when it comes to frequency response. There are a few exceptions to that rule but they would not appear to be in place here. I will give you one scenario where the amplifier might be at fault in a circumstance where the client claims to hear small differences between channels after a repair has taken place. "As to when the problem became most noticeable - ummmm - I think it may always have been there, but perhaps I just noticed it more (?) after the NAD "blew up." The repair shop guy claimed that, when he re-did the cracked solder joint, he "swept" the whole amp and found it fine. I gotta trust him in this, though I'm willing to take the NAD in again for another check-up if there's any chance it might be the culprit." I somewhat hate to provide this information as it can lead to some heated arguments that most often cannot be resolved but here goes ... Electronic components have what are called "equivalents". Obviously, a film resistor is a film resistor as far as specs are concerned and a designer's choice for a metal film resistor in one location in a circuit, say, a phono pre amp, should be respected when replacements are made. More broadly a resistor is a resistor and substituting a wire wound resistor for a film resistor will not affect static measurements such as frequency response, particularly in a crossover where the choice of suitable components is somewhat limited. Most semi-conductors have equivalents and the most commonly used in audio are transistors which come into and go out of production over the years and are available in several varities from several manufacturers at any one time. The service manuals for any product will guide the service tech to three or four transistors which are considered to be equivalent to one another when used in a circuit. It does not appear to have happened in your repair, Larry, but on occasion when the techs would repair an amplifier after having substituted an "equivalent" transistor the client would claim the amplifier didn't sound as it had before the repair. This might happen in one out of 1000 repairs on amplifiers and tyically it appeared more often when the amplifier had outlived its original transistors' manufacturing life. The problem was slight and I can't recall anyone ever claiming to hear 4-6dB boost in frequency response due to an equivalent component being inserted. Those using tubes would be more familiar with the "sound" of one tube not being exactly identical to another tube of the same type. This is the sort of minor difference you can also find in "equivalent" transistors. So, the situation is quite rare to begin with, it does not appear to have occurred in this case and normally has no real resolution in the end. You can certainly ask the tech if there might be anything they did inside the amp which could cause a change in response but I strongly suspect the answer will be "no" and from the other things you've said I would have to believe them. It appears they did not install any active devices such as transistors. Simply resoldering a bad connection would not cause a frequency response shift in an amplifier. And, just to be clear, even if such a substitution had been made to a transistor, the shop is absolutely within its rights to do such an exchange and NAD has provided guidance and given permission to do such exchanges. As far as NAD and the shop would be concerned the repair was done as it should be. Additionally, you will get no traction telling most techs that one transistor "sounds" different than another equivalent transitor. Unless the shop or the technician offers there could be something they did to the amplifier, I wouldn't even cross the threshold of "equivalents", Larry. Here's the simple test - which I believe you have already performed - to determine whether the amplifier could be involved in this issue, swap speaker leads channel to channel. Repeat this set up ... "Pull both speakers out into the center of the room and place them immediately side by side. If possible, place the amplifier into a mono mode to ensure both speakers are seeing identical signals. While playing a selection that shows the discrepancy pan back and forth with the balance control." ... and after confirming the problem is evident in one channel, swap the leads to both speakers. If the sound from one channel does not transfer to the other speaker, then the amplifier has become a very unusual suspect in this case. . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2182 Registered: Oct-04 | Thanks (again) Jan. Mer, knowing the level of my desperation, suggested one thing which I had not done: just switch the RCAs on the Oppo input into the NAD. I did this, and then did my usual test with two chamber CDs that I know well, and love for their overall clarity. When I switched R-L connectors, the high violins - obviously - now came through the R-hand speaker. In both CDs, the high violin sound on the R-hand speaker was clear and, to my hearing, without much distortion. Not the boosted high sound that comes from the L-hand speaker. I then switched the RCAs back to their normal position - double checking the inputs to be sure the plugs were correctly sited - and then played the CDs again. Whoosh - the very high violin sounds were again sizzle-prone and sounded (again) as though I'd boosted the treble by 4db or more. I checked the tone controls on the NAD - three times - and they were set at 0, or "flat." I know what you've been telling me, Jan (even though I sometimes don't understand all the physics involved) and despite having taken out and "measured" the L-hand speaker crossover - seeing no discoloration or bulging - having the B&W tech tell me that the readings are "OK," (his cryptic comment) I have no reason now to suspect ANYTHING BUT the crossover. I've read Jan's last several postings many times, and have followed the suggestions of everybody kind enough to post on this thread. SIGH. Bottom line: should I now take the speakers in to the shop for their own listening tests? I think that's about all that's left - other than ordering a new crossover from B&W ($68.00) Mer has gently suggested that I'm starting to spend way too much money on the speakers. . . . . . Respectfully. . .LarryR |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14740 Registered: May-04 | . I think another opinion on this is in line. |
|
Gold Member Username: MagfanUSA Post Number: 1001 Registered: Oct-07 | I don't mean to be trite, but once sorted out you won't have to mess with any of this again for quite a while. hopefully ever. "When you have eliminated the impossible, whatever remains, however improbable, must be the truth?" Sherlock Holmes: At this point, I'd load the speakers into the van and take them someplace for a test. If you still have the original tweeters......I'd bring them, too. One last 'Hail Mary'. Has all your speaker wire swapping been done at the speaker? If yes, than I'd try swapping at the amp. |
|
Gold Member Username: My_rantzGold CoastAustralia Post Number: 3095 Registered: Nov-05 | I'm sorry Larry, but I read through your last post three times. You swapped the RCA L&R connections from the Oppo to the NAD and the offending sound was not audible. When you swapped them back to their normal position it came back. Did you swap the connections at the Oppo end or the NAD end. Or both??? If the former, then doesn't this make the Oppo a suspect? |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2183 Registered: Oct-04 | Ok, guyz - here's what I did today, before I evacuated the premises and took the car in for service. (Grin) Switched out the RCA plugs where they connected from the Oppo into the NAD. Played the two CDs, and proved to myself that the distortion stayed with the L-hand speaker - did NOT migrate to the R-hand speaker, even though the high frequency side of the CD was now there, as in "this is the side with the high violins." When I switched back to the normal connections, the problems remained with the L-hand speaker. No matter what I do - the distortion and turned-up treble, whatever you want to label it, stayed always with the L-hand speaker. I switched cables, though frankly I found this a foolish gesture. But I did it, anyway. NO CHANGE. Now - good folks - in my feeble-minded way of thinking - the ONLY possible problem could be in the offending speaker's crossover. I've isolated absolutely everything else. Tested and tested and tested, and there is a constant problem here. So - my question: should I take the speakers into the shop and pay them $75 just to take them in and listen to them - plus $175 minimum if they have to replace a component? Or - should I call B&W and get a replacement crossover for the "offending" speaker and see/hear what happens??? Either way, I'm out a lot of money that Mer is beginning to complain about - which is NOT good! SIGH. sigh. DOUBLE SIGH. Respectfully. . . LarryR |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14741 Registered: May-04 | . Is Mer in agreement there is a problem? |
|
Platinum Member Username: NuckPost Number: 14822 Registered: Dec-04 | Is there anybody else to drop by and give a critical lisen? Prompted by Jan's post above. I really mean it Lar, wish I was there. |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2184 Registered: Oct-04 | Unfortunately, none of our Swampville friends is able to help out. They're mostly pop and "oldies" fans who have no concept of opera or chamber music. Mer does, indeed, realize that there's a problem - but (ahem) she's going through a very rough time right now - art isn't coming as it should, and the Art Center and its problems. . .well, let's just say things aren't too great around here at the moment. So, she's not really "tuned in" to my problems. DOUBLE SIGH. I've tried to get her to do some critical listening, but can only push things so far with out other kinds of "distortion" coming into the pikchure, if you catch my drift. So - I'm left with a coin-toss. Heads I take in the speakers for some further testing - and at a minimum $75 cost. Or I toss out $68 plus a bit of shipping for a new crossover - and hope for the best? The shop will charge me a minimum of $175 to test and replace the crossover, BTW - plus the cost of the crossover itself. It's that much of a birchy job. I've read on several forums about people who have crossovers that become "screechy" - but usually because they over-drive the speakers with rock music. SIGH. So, what's a poor(er) old mope to do? Flip a coin? Respectfully. . .LarryR |
|
Gold Member Username: MagfanUSA Post Number: 1003 Registered: Oct-07 | Wow, decisions.....decisions. Can't any of your friends that are at least familiar with MUSIC hear what is wrong, too? Believe me, Opera and I don't get along well, but I'd sure like to give it a shot. One last try:: Replace interconnects. Borrow some if you have to. Try to borrow some speaker cables as well. If, as I fear, there is no change in result, you may end up having to bite the bullet. I know things are tight, heck, if you looked in my wallet you'd go pale. ( no cracks from peanut gallery, please) I'm so broke I can't pay attention. I've been pulling weeds for the last week. If you want to try a DIY, pay somebody the 75$ to tell you the x-over is toast. Buy the part and than save yourself what looks to be well over 200$ by so doing. Might they do a house call to hear the system as installed? Naples is kind of upscale and I know it's changed a LOT since I lived down there. So worst case you drive the Alley over to Miami for a spin down Calle Ocho. Can any of your swampville buds help with an amp or source to test against your current equipment? |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2185 Registered: Oct-04 | Believe it or not, none of our "local" friends have any idea about HiFi stuff. The one guy who did got divorced and lost everything - and the one guy who Mer knows, and who had a great kit, has gone "Nawth" for the summer. SIGH. I switched out interconnects - but not speaker cable, which is nearly new and couldn't - in my own way of thinking - cause the highs-only problem. Yeah,Naples is very upscale - except the area of Collier County where we live. I think you'd call it the "service employees" area. GRIN We're used to kitchen doors. . . . . Anyway - I'll sleep on everything and make a final decision in the ayem. I have to go cautiously here - Mer got very upset with me when I had the speaker all "gutted" and lying in pieces on the dining room table. I don't know what she'd do if I told her that I'd have to buy new speakers!! (don't wanna know. . .) REspectfully. . .LarryR |
|
Gold Member Username: My_rantzGold CoastAustralia Post Number: 3097 Registered: Nov-05 | Switched out the RCA plugs where they connected from the Oppo into the NAD. Played the two CDs, and proved to myself that the distortion stayed with the L-hand speaker - did NOT migrate to the R-hand speaker, even though the high frequency side of the CD was now there, as in "this is the side with the high violins." When I switched back to the normal connections, the problems remained with the L-hand speaker. No matter what I do - the distortion and turned-up treble, whatever you want to label it, stayed always with the L-hand speaker. Larry, maybe to satisfy yourself fully, you could swap the RCA's from Oppo at the NAD once more, but this time swap the speakers as well. If the high frequency sound did not distort in the right hand speakers as you stated, then this time, since you swappped them, it should. Be sure to swap the speakers back again so you don't get them confused. Not that I think you would, but it's easy to get sidetracked. After everything else you have tried this should prove to you the problem lies somewhere in the left speaker, the crossover perhaps as you've investigated. Sorry to hear about Mer's problems, but tell her she at least needs to keep her man happy as it's no good having deux 'les miserables' dans la maison. Happy Easter anyway and same to all. |
|
Gold Member Username: MagfanUSA Post Number: 1005 Registered: Oct-07 | You know, the clue nobody has 'q'd in on is that when Larry started up from stone cold, it didn't do it. Something in THAT speaker is getting warm and for lack of a better word.....changing. I've got 1$cdn that says it's still that crossover. I can only think of 2 things to try. A/B the crossovers between speakers and see if it follows..... OR, run the speaker open with the crossover visible and spritz it with some canned air to chill it while it is making that 'noise'. Spray one part at a time and listen for a crackle. That's the offending part. |
|
Gold Member Username: My_rantzGold CoastAustralia Post Number: 3098 Registered: Nov-05 | That was discussed Leo, if you back up a few threads. Advice was given, however I think even Larry admits he may be getting over his head a little on actually taking action himself on certain things. Personally, with those speakers, and while endeavoring to maintain a reasonable resale value, I think if he is pretty certain he's narrowed down the problem, he's better letting a techie do the work rather than having some little accident and making matters worse. But that's my two cents worth. |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14742 Registered: May-04 | . Next new pieces of advice: First, a question; have you tried any other source? So far, all I've seen are CD's being used for testing - and that only from one CD player. You've indicated the problem existed before the introduction of the Oppo, now you need to test further. Certainly good source material should be a part of your testing but you also need to determine whether a problem is consistent with various source players. Does the same problem exist with FM? Assuming it does, we move on to ... Second, I mentioned earlier you could attempt to reseat a cold solder joint with a medium wattage soldering iron. You did not respond to that suggestion. I assume you're going to need a soldering iron to make any new primary connections to the crossover board should you decide to purchase a complete replacement. IMO, you should try to repair a faulty solder joint first. If that fails to solve the problem - and it might, cold solder joints can also ocur at the lead out from a component which you cannot repair, then your next logical step would be to swap the crossover boards between the two speakers. Your best diagnostic tool at this point is a speaker that is not having problems. Read the last sentence again. Obviously, should the problem move with the crossover board, you've diagnosed the general area of the problem. Success!!! If you get to the point where you have identified the general location of the problem, then you can move on to; 1) replace the entire board for a set cost, 2) try to further narrow down the specific component that is failing. Leo's suggestion for cooling the components is a good way to begin such tracing. From what you've said the resistor setting the tweeter level would be a first choice. Or you could buy a new resistor of the same value and make a simple replacement. All of this assumes you know how to solder well enough to not create a cold solder joint, Larry. If you don't or you are uncertain of your skills, then what good would it do you to order a new crossover anyway? Someone else is going to have to install it and you're right back at the service shop for that procedure. If you can solder, perform a few more simple tests to determine whether the crossover is the obvious culprit. This should take a morning's time. If you can't solder, then you need to pay a technician for their skills no matter where the problem exists. If the crossover board has push on terminals for its primary connections, swapping the boards between speakers is relatively easy. No further testing is required. The swap will determine the location of the problem well enough to tell you whether you should order a new crossover. You've reached s**t or get off the pot time, Larry. I'm sure things will be better with Mer if you get this resolved. . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2186 Registered: Oct-04 | AN EXHAUSTING MORNING! Well - after reading and re-reading all - have patience - here's how I spent my morning. Taking Jan's suggestion as to alternate sources - I tried FM, but our NPR station has gone all-chatter. Dialed around, but the only stations that come in clear have pop/rock or religious - and as you know, they're all compressed and tweaked. Not good choices, though I did try one, and found no speaker difference that I could easily determine. Not a good test, though - Rock doesn't have many violins! BIG GRIN OK, OK - then I went into storage and hauled out my old and trusty Oppo 980 - which I was going to donate to charity, but fortunately have not yet. Hooked it up and immediately was struck by the sonic differences between it and the 83SE! Wow! Anyway, I played the same discs on the 980 - and found LESS distortion on the L-hand speaker, but it was still there. Swapped out the cables, and the high-freq fuzz remained with the same speaker, didn't swap with the cables. Put the 83SE back online and the L-hand speaker highs were again accentuated - but then ALL the highs in both speakers were more "there" than they are with the 980. As expected. . .better DACs?? OK - Mer went out to buy some art supplies (whew!) and I went a-hunting for my "old stuff," including an aged but still-good chisel-tipped soldering "pen." I hadn't used it in about ten years. . . Un-screwed the 705 back plate and got the crossover out far enough so I could tip it up and prop it so it wouldn't move. Heated up the pen and set it against the leads - apparently 14AWG! - going to the speakers. Watched the solder liquefy then quickly pulled the pen away and let the solder cool on all four leads. BTW, I'd put alligator clips on the wires to keep the heat from migrating toward the speakers. The wires heated up only slightly. Tested the joints - they did not look "crystally" and seemed very tight. Put the crossover back in place - tested all again - with THE SAME RESULTS. Obviously, the joints were/are OK. To switch out the entire crossovers would mean tearing apart each speaker, going down to the tabs on each, pulling out the wires - then reversing all. Unless absolutely NECESSARY I ain't gonna go there. No cold-spray available - sorry. Put the speakers out close together and put in the Aix records frequency sweep disc that came with the 83SE - ran each speaker up and down a half-dozen times and noted each time that the highest tones - above about 5kH - were slightly louder on the L-hand speaker. Reversed the channels and the sound levels remained the same - the L-hand speaker still slightly more "pronounced." Kept the speakers out close together (about 3 feet apart) and played a sensitive track on one of the discs - where the piano goes through a glissando and then the violin takes a cue and goes through several arpeggios - quite high notes. The music here is "fast and furious," and I thought this liddle, about 40-second, section would be a good A-B'er. In EVERY case - swap speaker leads or not - the L-hand speaker was more pronounced in the very high end, with a "ragged" quality to the very highest notes. Still thinking that theOppo might be at fault, I plugged back in the old 980 and ran through the same routine. Although the 980's high notes are nowhere as clear as the 83SEs, the same sonic problem persisted. After all this - I have little reason to conclude anything but that there must be something amiss with the crossover. I did e-mail Oppo, though, and await their (probably incredulous) reply. SIGH. Went into the kitchen and let the music play on - and noted with despair that the highest violin tones from the CD assaulted me much like the screech of our smoke alarms - very similar sound. DOUBLE SIGH. I then called the repair shop and talked with "Bob" the guy who does the testing. When I finished my description, and told him all I'd done - all he could say was "sounds like a bad tweeter." Yeah, one of my two brand new ones from B&W. . . He said he'd do basically what I've done - but would take out the crossover and put it on several of his testing gear - that he would, indeed, cost me three or four hours' labor, at $45 an hour - plus parts. He said he would not agree to a "simple listening test" because he would not be sure of anything without his "scope readings." SIGH. So there I am - Jan - I'm about to get off the pot and call B&W - and if they send a crossover and if it doesn't work and if I'm still sober - I'm thinking seriously of an iPod and some Bose speakers. . . . .GRIN???? Respectfully. . . what's-left-of-LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2187 Registered: Oct-04 | A BIG OOPS - SIGH Sorry, Jan - I simply overlooked the solder joint testing on the resistors themselves. I DID do that, as well as the leads to the speakers - and put the alligator clips between the board and the resistors. All joints were very difficult to reach - but I (think I) managed to re-heat all and let them cool slowly. If there were any cold joints, there are none now! Please just insert this into my last posting. Old men should double-edit their work before sending it out!!! GRIN Respectfully. . .LarryR |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14743 Registered: May-04 | . "I then called the repair shop and talked with "Bob" the guy who does the testing. When I finished my description, and told him all I'd done - all he could say was "sounds like a bad tweeter." Yeah, one of my two brand new ones from B&W. . . " Yes, it does sound like a bad tweeter simply because the tweeter is far more easily damaged than any crossover component. His comment, however, generally assumes damage which seems doubtful here. At best he has missed the fact you've swapped tweeters between cabinets at least once if not several times. And you are convinced the problem stayed in the one cabinet - right? If you want to do without your speakers for a week or so, ask B&W to check out the tweeter. It's relatively new and should be covered under a replacement parts warranty. I would hope B&W would perform the test without charge under warranty with you only being responsible for shipping both ways. The question here would be which tweeter do you send them if both appear to be functioning as intended? Otherwise, list out what you have done as best as possible in a logical order, send that list to B&W and ask for their advice with the idea you have apparently discounted all other possibilities beyond a defective crossover. I guess we never have established whether these speakers might still be in warranty under the original five year plan that comes with any B&W. Or, if we have at some other time, I don't remember the answer. None the less, replacement parts have their own warranty. At this point, Larry, I would order a new crossover unless B&W is gracious and has a better scheme. From what you've said, you could purchase a new crossover and a new tweeter if need be and still not arrive at the charges the shop would levy. . |
|
Gold Member Username: MagfanUSA Post Number: 1006 Registered: Oct-07 | I give. short of swapping the x-overs between speakers, I can't think of anything to do at this point. Larry already said that swapping tweeters didn't change the speaker with the problem. Back to X-over. No CANNED AIR?, Larry? :::::::::::::::::::::::::::::::::::::::::::::::::::: |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14744 Registered: May-04 | . I'm hoping you've covered this in your experiments, Larry. Just to further clarify where the problem might exist, have you listened to these same "test" CD's on any other system or through headphones? This could still be very much a digital recording issue and your selection of music so far has only shown the problem to exist with violins and orchestral compositions. Right? What is the one most common complaint from classical music listeners regarding CD sound? Harsh, raspy, spitty high frequencies centered around violins. From what you've stated, it would not appear to be a problem with the discs but you should make sure. You've eliminated everything else, Larry, go ahead and make certain this is not a problem with the source discs. Even some cheapo headphones from the $ store would start to tell you something. Or, have I got this wrong? Have you heard this problem with other types of material that you know to be a clean recording? . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2188 Registered: Oct-04 | First (BLUSH) Sorry, Leo - no canned air. I just use Swiffer cloths. OK, Jan - I've tried this experiment with several discs - both CD and SACD with one or more high-pitched string instruments involved. Always shows up - except for just two times when the problem "seemed" to go away when the kit was stone-cold. Today, however, I fired it up, and the problem was there from the start - even got a tad worse after an hour of heat-up. SIGH. Almost forgot (again) yes, I listened to the several test discs with my $200 Sennheiser earphones - both channels came through clear every time. I think that squelches the amp/player possibilities? Just asking. . . You may remember I bought these speakers used off AudiogoN - and they were made in 2003. No warranty, for sure. Well - I give. I'm on the phone to B&W. TRIPLE SIGH (haven't done one of those recently - GRIN) Respectfully. . .LarryR |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14745 Registered: May-04 | . "I think that squelches the amp/player possibilities? Just asking. . . " I would think so, Larry. This is where I have to defer to what you believe you are hearing. . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2189 Registered: Oct-04 | Ah, yes - what I think I believe that I may or may not be hearing. DOUBLE GRIN Well - I just e-mailed an order for the new crossover - if the B&W shipping is as before it will get here in about 10 days or so. At that time I shall install it, test it, and report on whether or NOT is resolves the problem. If it does not - well, I'll just listen with my "non-distorting" earphones! (have to toss in another triple-sigh - - sorry, Jan, for the "overload") Respectfully. . .LarryR the miserable |
|
Platinum Member Username: NuckPost Number: 14827 Registered: Dec-04 | I wish one of us could be there to concur Lar. Keep Mer happy mate, unless you like the couch. Kudos for pulling out the iron! |
|
Gold Member Username: MagfanUSA Post Number: 1010 Registered: Oct-07 | If you DON'T update this after the install of the crossover, I'm driving to Naples and picketing your house. SAVE the old crossover. B&W may be interested in it if it WAS the problem. They'll be able to tell you if / what is the problem. Jan was correct from square #1. This is NOT something that fails in anything less than the couple decade scale. |
|
Platinum Member Username: NuckPost Number: 14833 Registered: Dec-04 | Since your system is gonna be down anyhow, ship the tweets and have them tested gratis. If they say no, give them a list of members here that they might want to call, in regards to their future goodstanding in the audio circles. Lar, I emailed you my cell # to give them. |
|
Gold Member Username: MagfanUSA Post Number: 1013 Registered: Oct-07 | here here |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14748 Registered: May-04 | . "here here" Oh, no! Not the "here here" or "hear hear" debate again! This is worse than the cable threads. . |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2191 Registered: Oct-04 | "There, there" now, Jan! (a grin too big to fit on the page) |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2192 Registered: Oct-04 | Well, YOU brought it up, Jan! Quote: from Wikipedia - - Hear, hear is an expression used as a short repeated form of hear him, hear him. It represents a listener's agreement with the point being made by a speaker. It was originally an imperative for directing attention to speakers, and has since been used, according to the Oxford English Dictionary, as "the regular form of cheering in the House of Commons", with many purposes depending on the intonation of its user.[1] Its use in Parliament is linked to the fact that applause is normally (though not always) forbidden in the chambers of the House of Commons and House of Lords.[2] It is often incorrectly spelled "here here", especially on websites[ |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14752 Registered: May-04 | . Well, well! |
|
Platinum Member Username: NuckPost Number: 14840 Registered: Dec-04 | Huh... And hear I always spelled it 'hear hear' cause this is an audio forum. |
|
Gold Member Username: MagfanUSA Post Number: 1022 Registered: Oct-07 | Thanks for the grammer lesson. I'll check this out in my Strunk and White. |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2193 Registered: Oct-04 | I'll bet you'll find Strunk and White also urging you on to use correct grammAr in many applications where grammAr is important. (grin) |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14753 Registered: May-04 | . Grammer/grammar, it's all sow, sow. |
|
Gold Member Username: MagfanUSA Post Number: 1024 Registered: Oct-07 | No, I tend to make it up as I go along. It keeps my creative streak in czech.....or latvian? |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2194 Registered: Oct-04 | Hmmmm - it's getting to the point where I feel the need to wash my hands after dealing with this thread! DOUBLE GRIN Good humer, tho. . . . . Respectfully? LarryR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2195 Registered: Oct-04 | B&W seems to have disappeared. No answer to my e-order or follow-up e-mail last week. Hmmm. . . Oppo, meanwhile, took the time to send me a detailed "this is how your test for HF distortion" checklist. They said - first - if the sonic problem stays with the "offending" speaker when you switch channels or switch it out L-R in the room, the speaker is at fault. OK - so far I'm right. They had me do everything from all that Jan has suggested to taking down the Oppo's settings, returning it to factory default, and re-setting everything. Nothing changed. SIGH. So - Mer and I are spending a long weekend - waiting. I did get an e-posting from a guy in Chicago whom I trust HiFi-wise. He said flatly: "anytime I replace a tweeter I replace the crossover, as well." Interesting. He said he's found that there are more subtle crossover problems than most people realize. He also said "don't trust your meter readings on resistors/caps that are on the board or connected in any way to other components of the crossover - the only way to get a true value is to isolate the component completely." As I'm not going to un-solder anything, I'm stuck with my initial readings, which didn't seem far off the mark. Well - that's another topic for argument, I guess. I worked with him a long time ago - he's part-owner of a hi-end stereo emporium - and he said to tell all you Dawgs that the suggestions/information you've been feeding me are quite correct. He reads, but does not participate in, any audio forums for some reason. Perhaps sanity? GRIN For those who celebrate it - Happy Easter. Or Passover. Or a Holiday or your choosing. Mer says she's still trying to find a Pagan one. . . Respectfully. . .LarryR |
|
Gold Member Username: MagfanUSA Post Number: 1031 Registered: Oct-07 | The Seinfeld Solution: Festivus....The holiday for the rest of us. |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2196 Registered: Oct-04 | Yeah! I like it! Thanks. . .LR |
|
Gold Member Username: Larry_rNaples, FL Post Number: 2198 Registered: Oct-04 | So on April 1st (should-ah known better) I e-mailed an order to B&W for a new 705 crossover. Today, I e-mailed a "hello, did youz guyz get my crossover order?" An hour later I get this e-mail: "Did you want to order a crossover?" Well, I did my usual count-to-10 before answering - and put in an order for a crossover. Again. . . This may not bode well, eh? SIGH Respectfully (at least to y'all) LarryR |
|
Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 14761 Registered: May-04 | . The guy who's taking orders isn't the same guy who's building crossovers. |
|
Gold Member Username: MagfanUSA Post Number: 1040 Registered: Oct-07 | Or even the guy with the padded bag and roll of stamps, for that matter. |