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New member Username: RjohnphilPost Number: 1 Registered: Sep-12 | I am having a problem with a couple of zones in my new Niles ZR6 Multizone receiver. - Fried the amp of my first ZR6 after a week. Niles replaced. - My friend assumed the problem related to a few "shiners" that had shorted my speakers. I wasn't convinced. Fixed the shiners however. - New amp immediately shut down with amp failure message. None of the zones were even powered on. Just connected the speakers and keypads, turned on the power the system immediately shut down. It went into protect and is fine. - Narrowed the problem down to two zones with pairs of Jamo IC606 speakers incorrectly set to 4 ohm rather than 8. These speakers, run in parallel had an impedance of 2. Assumed that caused the amp failure. Switched impedance to 8. Amp still fails when these two zones are hooked up. - Test Jamo's with my old Denon AVR 3600. They work fine in their location in the ceiling. - Tested the Jamos with a short length of speaker wire right at the back of the Niles. They won't work. - Got a new pair of Jamo IC408s. Tested them with short speaker wire at the back of the Niles. They work fine. - Installed new Jamos in the ceiling and hook to Niles. Niles amp fails. Pull Jamos out of the ceiling and test them now at the back of the Niles. Niles amp now fails with the speakers that minutes before had worked perfectly. - My friend also tested the Jamo IC606s that I pulled out of the ceiling and replaced and they work fine on his Niles ZR6. - I am pretty ignorant but this is a mystery to me as it seems like I have tested all of the possible variables. The speaker wires run to the ceiling for these two zones work with my Denon and I test continuity with an ohm meter. Any thoughts on how to proceed with this would be appreciated. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17421 Registered: May-04 | . You've essentially covered the bases with your testing. Have you unplugged the unit and allowed it to sit for a few minutes to see if it resets itself? Is there a reset process mentioned in the owner's manual of the receiver? Who did the pre-wire/install? Do you have any recourse through their warranty? Or, is this a system you've sort of put together from pieces and they have no responsibility other than getting wire from point A to point B? If you are left to figure this out on your own and this is what you've done ... " Got a new pair of Jamo IC408s. Tested them with short speaker wire at the back of the Niles. They work fine. - Installed new Jamos in the ceiling and hook to Niles. Niles amp fails. Pull Jamos out of the ceiling and test them now at the back of the Niles. Niles amp now fails with the speakers that minutes before had worked perfectly.", then I'd call the receiver unstable and I'd contact Niles tech support. Posssibly they will have an answer, or possibly they will have another reciever to send out. I really see nothing else you can check yourself at this point other than the reset. . |
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New member Username: RjohnphilPost Number: 2 Registered: Sep-12 | Thanks Jan, This is new construction. I ran all of the wire myself and installed everything. I will do as you suggested. I have talked to Niles support and they haven't mentioned a reset on the ZR6. They told me that they thought my Denon was probably a more rebust unit and that is why it was able to power the speakers in their ceiling location. Thought it could still be a wiring issue somehow. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17427 Registered: May-04 | . Doesn't suggesting the Denon is "more robust" say their unit is a piece-o'-crap? I haven't worked with Niles since I stopped selling audio several years ago - long before Niles was peddling their own receiver line. But any time a manufactuer suggested another line was "more robust" than their own I certainly would have taken that as saying their line was not at all "robust" - sort of puny in fact. Particularly when the comparison was still to another mass market line. "Robustness" comes from the power supply of the component which is the source of current delivery to the output stages of the amplifier. As nominal impedance drops higher current levels are required of the power supply to maintain the same amount of "power" according to Ohm's Law. If the power supply cannot deliver those higher current levels, or the output stages of the amplifier are internally current limited in an attempt to minimize failure, then the amp will shut down to protect itself from implosive - and at times explosive - damage. Admittedly, most mass market receivers, and especially multi-zone HT recievers, are not built for sustained high current delivery. However, unless you are asking for fairly high volume levels from the amplifier, IMO most amps today should be able to drive a fairly consistent 4 Ohm load without immediate shut down. I'm not at all familair with Jamos' current line of in wall speakers so possibly there's an issue with the speaker that would make this something other than a fairy consistent load. However, the fact one mass market amp can handle the load without apparent problems while the Niles immediately shuts down - or won't even power up - does not, to me, say much for the Niles design and exectution. When you say, " Narrowed the problem down to two zones with pairs of Jamo IC606 speakers incorrectly set to 4 ohm rather than 8. These speakers, run in parallel had an impedance of 2. Assumed that caused the amp failure. Switched impedance to 8.", where did you make the switch? Are you using autoformer type volume controls in each room? Is this just a "protection" type load resistor thrown in series with the speaker load? Or, was the switch made on the amplifier itself? If the autoformer vc was loading the amp, the actual load on the amp should have remained relatively high and stable. If the switch is on the amplifier, this is merely a current limiting device which will not allow the power supply to produce, or pass to the outputs, sufficient amperage to drive low impedance loads. This, the latter method, is a pretty cheap way of getting around having a not so great power supply in your amplifier. I guess I should ask, why run these two pairs of speakers in parallel? Why not make a series connection which would raise the total impedance load on those channels of the amplifier and make the system more stable? . |
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New member Username: RjohnphilPost Number: 3 Registered: Sep-12 | Jan, The speakers themselves have a switch that allows you to change from 4 to 8 ohm. Regarding the series vs. parallel connection, as far as I know that is the way that Niles is configured with their modular plugs. I did pull the plug on the niles last night and it had no effect. The system flashed amp failure immediately after cycling through its initial start-up stuff. Do you have any thoughts on why the Niles worked fine with the replacement speakers when I plugged them in out of the box directly to the back of the unit. Amp failed when trying them out in the ceiling and now it fails as well when I test them directly at the back of the unit. Thanks |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17428 Registered: May-04 | . "The speakers themselves have a switch that allows you to change from 4 to 8 ohm. Regarding the series vs. parallel connection, as far as I know that is the way that Niles is configured with their modular plugs." If I understand that correctly, the speakers have a switch which allows for the impedance change? How is that accomplished? Just a load resistor inserted in line? That would be the most econimical way for Jamos to do this. Also, the least efficient. Or, is there a small transformer mounted on the speaker? I'm sorry to say I'm rather glad I'm not selling audio today. This stuff has gone from being silly to be completely ridiculous IMO. So the Niles modular plugs do what? One way they are in parallel and another way they are in series? Please explain. "Do you have any thoughts on why the Niles worked fine with the replacement speakers when I plugged them in out of the box directly to the back of the unit. Amp failed when trying them out in the ceiling and now it fails as well when I test them directly at the back of the unit." You mean other than this? And this; http://www.cpsc.gov/cpscpub/prerel/prhtml10/10724.html These are old recall notices but they might have something to do with your current problem. I'd like to think no manufacturer is foisting off junk gear but I know that isn't always the case considering how mass market components are designed and assembled today. And Niles hasn't had to remove the receiver from the market so that must mean the component has some merit. The Niles site's blurb states the amp is "stable" down to four Ohm loads. I'm going to assume you've completely wrung out the wiring to make certain there are no posibilities for even a single crossed conductor. And that each and every connection you've made is absolutely 100% good without stray strand(s) of cabiling which might cause a shorted output. If you did the wiring before the drywall went up, a common problem is a staple has been run through the wiring somewhere along the run. The next question would be regarding the guage of the cabling. If there is sufficient resistance in the cable over a very long run, then the total impedance of the load will drop and could be enough to cause the amp to fail. That's not likely since that would still suggest an amplifier that is barely hanging on to stability by its fingernails. Why the amp ran with the speakers directly connected to its outputs would, at first, suggest the amp can handle the load though you might not have been playing at a high a volume in this set up. That the amp shut down once it was connected to the wiring would, of course, suggest a problem in the wiring. Return to my above questions for that. However, once the amp shut down I suspect sufficient damage was done to the output stages to have the amp see a dangerous situation from then on. Some amps have what's called "crowbar" type protection circuitry which will cause a shut down until that protection is removed or reset. My guess would be the Niles has such protection to keep it from being permanently damaged when it's been connected to faulty wiring or a too low impedance load. Both conditions are fairly common when installs are done by minimum wage staff who have just today been promoted to "installer" class after the last guy threw his wire strippers through the front window of the shop. I've seen lots of boggered installs done by not so bright workers so most audio component companies that have to deal with these situations have built in protections which minimize the damage to their gear. Like I said, I haven't worked with Niles in years so I can't say anything specific but that would be my guess, Niles just doesn't want someone to set off the protection, reset the amp and then try again without correcting the problem first. That answer would imply Niles has a reset function. Only they can answer that question. If, on another hand, the second Niles receiver is defective as it came from the manufacturer, then I would begin to question the value of the Niles receiver when there are other alternatives. Possibly not as neat and one package solutions, but solutions. As I used to tell my clients, any component sounds better in your home than it does in my repair shop. . |
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Gold Member Username: MagfanUSA Post Number: 2890 Registered: Oct-07 | Sounds almost like the old 'nail thru the wire' trick. |
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New member Username: RjohnphilPost Number: 4 Registered: Sep-12 | It doesn't seem likely. The zones are near each other but separate. They worked initially and failed at the same time. They are the only zones with the Jamo IC606s. Both zones worked as well with my Denon. |