Glass Wolf Question
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Silver Member Username: Lil_jonPost Number: 104 Registered: Jul-05 | I can never rember to call RE and ask what will the RMS be on there New XXX have you called them and asked? Im hoping its 2000 watts RMS I would love to hook an orion 2500d to it. |
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Anonymous | why component sub manufacturers dont use the AES or EIA spec. for sub power???? thermical spec is correct whis AES ou EIA... RMS ou max is not signifiant...because not indicate the range fréquency and time for mesure.. I am french thank for your forum very very good |
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Silver Member Username: SouthernrebelMonroe, Louisiana USA Post Number: 940 Registered: Mar-04 | I dont think RE has released any specs on the new X.X.X. All I know is it has like 5" peak to peak excursion. Depending on how the specs look...i may have to pick up a 18" when they are released.  |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9828 Registered: Dec-03 | yeah I haven't heard too much regarding the new XXX specs yet. I'll have to call and talk to someone there when I get some time. As for speaker specs and power handling, I've written an article about power handling specs on speakers here: http://www.wickedcases.com/caraudio/speakerpwr.html If you want good power measure for within-linear performance use DUMAX ratings, but the issue with power needed versus thermal ratings is that the power needed fluctuates drastically based on both frequency being produced, and enclosure design. It's not a purely mechanical factor based solely on the speaker's anechoic specs. |
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thxrd Unregistered guest | yes ,thank, but the loudspeaker has two limit for the power... 1) mécanichal (ok fréquency /enclosure design I know 2) but the second is thermical limit of voice coil.. this mesure is not very easy but is a "standard mesure" the name in the audio pro world is :power AES or EIA it is very very clear 2 hours or 8 hours between 40 at 400hz... at ??? watts sinus or pink noise this limit is clear... the marging is 3 OR 6 db for crest factor the degrees of voice coil is max 150° at this day the max really technically possible is about 1000W ... after it is impossible to dissipate the heat... but it is possible to powered at 2000W for one ou two secondes.. but this capabilities is not sure and not réalistic why manufacturer for car audio sub not use this mesure??? the X max is not sufficient.. because at very low fréquency he depand of enclosure..ok and if he is necessairy to powered at 2000 or 3000 w for maximum X displacement the breakink is not méchanical but thermical... in my opinion, the fantastic X max (RE /adire ect...) are possible only for 1 or 2 secondes.. I modelise this parameters and all the sofware confirm this opinion... what do you think Roland |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9865 Registered: Dec-03 | you apparently didn't bother to read my article on thermal power handling specs I posted for you. power handling ratings on speakers ARE thermal ratings, since those are fixed values, unlike mechanical power handling which fluctuates based on teh enclosure. I'm aware of AES and EIA (electronics industry association)and for some things, the EIA specs are just too slack (THD measure for example) but anyway the fact is, higher quality companies do use standardized means of testing products for across the board comparisons, such as EIA, FCC, CEA2006, and DUMAX. Low quality companies use whatever they can to bolster their numbers to impress people who make the mistake of buying products solely based on numbers and not actual quality. To tell you the truth, specs only tell you so much. I can show you speakers and amplifiers with specs far "inferior" to other products in various catagories but in reality, even with worse numbers on paper, these products are more expensive, better made, and better performing in every way. |
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Unregistered guest | interesting response but not really clear more clear question if I powered a RE XXX 18" at 75 hz (or 200hz )in closed enclosure (small) at 2500W(real watt!!! ) by example: how many time before the voice coil burning... my opinion and my personnal test (with very big pro audio amp and calibrated real power): 2 /3 secondes... for the better 4" voice coil...in the world... the théorical X max is one spec but the thermical limite ( Power + time ) is a other important spec.. because not use the sub for run spl but for real permanent ultrabass use the AES ou EIA specs include thermical compressions.. not only distortion... the thermical compression is very important spec.. because incate the thermical limite.. one other remarque :nothing manufacturer indicate the X dammage (in car audio only..)why??? for the tumult(ADIRE) the X dammage and the X max is very very similar(1mm between each)I test personnaly (15") the X max is only théoric!!!because 1mm before the dammage is not serious situation for HP and ADIRE is very sérious manufacturer.. also RE.. I think all manufacturers exaggerate the specs (all spec) include the "sérious" manufacturers... I am AES menber for 30 years and I know very very good the AES Specs (and EIA) sorry for my very bad english |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9886 Registered: Dec-03 | "if I powered a RE XXX 18" at 75 hz (or 200hz )in closed enclosure (small) at 2500W(real watt!!! ) by example: how many time before the voice coil burning..." I wouldn't drive an 18" at those frequencies with any amount of power. The cone flutter alone would be horrendous. An 18" sub like that wshould be crossed over at about 50Hz, 18dBA/octave. On a XXX, the continuous power handling is 1600 watts, 2500 peak. You should not be feeding the sub any more than 1600 watts RMS anyway. The XXX isn't an SPL sub, it's purely a SQ sub. Xmax, Xmech, Xsus, and Xmag are all measured using a DUMAX machine, so all of those measurements are not at all theoretical, but objective, linear measurements, all made with the driver kept linear. Basically your argument is strictly that nobody uses your AES ratings and because you're a member it irks you. I understand. What speaker manufacturers ARE doing now is using the most accurate measure system for speakers around, which are DUMAX specs. Those can NOT be fudged, faked, or exaggerated. They're tested by a calibrated machine, and all TS specs are derived mathematically from there. I've been in the EIA myself being an electrical engineer, so I'm quite familiar with standards organizations, but the plain truth is the only way to get universal comparable specs on products is to have government regulatory control over the industry, and I'd just as soon not have to deal with that. I think my article was quite clear, but for the record, since I don't know what dammage is in French (one language I don't speak.. sorry.) here are Excursion specs commonly used in the US: Xmag Excursion limit due to the magnetic limitations of the driver's motor. Xmag is defined as the displacement at which the BL product has fallen to 70% of its value at the cone's rest position. Xmax Linear (one-way) travel of the cone. Xmax is used to determine the maximum linear SPL capability of the driver, and can be defined in a number of ways. The DUMAX definition is objectively the best one, and it is defined as the shorter of the Xmag and Xsus values, in each direction of cone travel. This definition is more useful than the older definition of Xmax, which was solely dependent on the length of the voice-coil vs. the length of the gap. Xmech Maximum physical excursion capability of the driver. Exceeding Xmech normally results in damage to the driver.Excursion limit due to the driver's suspension. Xsus The point at which the compliance of the suspension has decreased to 25% of the value at the cone's rest position. |
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Bronze Member Username: JakeyplaysbassPost Number: 20 Registered: Jul-05 | haha wow way over my head... |
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thxrd Unregistered guest | Yes yes; the X dammage is X mech in US... but my question is always the same.. nothing manufacturer indicate the X mech(in car audio and very few in audio pro) and very very few use Dumax (personnaly I use DUMAX BUT SINCERELY the dumax and X max are very simalar in fact.. and I have no questions on this subject.. and your response for the power is clear, but , my question is also very clear 1600W is not sufficient and not clear because not precise condition for mesure .. EIA?? /AES 8 hours?? /AES 2 hours?? / fréquency range??? crest factor ??? ect... 2500w peak is not signifiant...which conditions??? (nothing manufacturer for sub car audio precise the conditions..) and if I test at 75HZ (ou 200hz ou 55 hz) it is just for eliminate the mechanical excursion probleme at very low fréquency my project is super sub for home cinéma (8 X 18")(the enclosure is totaly in wall and in concrete and variable to 3 at 11 M3) drive by very hight power amplifier ( PRO audio Chevin or Crest.. 6 at 10 KW RMS ) and the fréquency range is 10 at 55 /60 hz I use the digital pro crossover BSS at 36 db/OCt NTM 366(New Tiele Method) my question is not for technical response (dumax /X sus/ ect... because I am engineer in pro audio and acoustic consultant but in France (and europe ) the real big subwoofer for very low frequency (car audio) is not present on the market and test ou comparison is impossible and your forum speak about many subwoofer (RE /Adire/tréo ect..) for me your experience is important but I want your User opinion... By example: you think really 1,5 inch one way X max is serious /and reliable ??? or juste just quasi equivalent at X mech anf just for 1 ou 2 secondes??? you think really voice coil support 1600W (for RE by example or other) real... how many times ???in your opinion my email is: thxrd@club-internet.fr |
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Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9944 Registered: Dec-03 | ok now it's making sense.. having context helps me understand what you want to do. RE tests tehir subs at continuous power handling for 8 hours straight if I recall, so it's pretty much indefinite. I know the Xmech and Xmax are accurate on the RE XXX because I use two 12" XXX subs in my car in an aperiodic enclosure, and the subs have been measured for specs on a DUMAX machine, so all excursion measurements are "within linear range" or in other words, without liosing linearity which is the ideal way to measure those specs for a driver. I think the reason many companies only advertise Xmax (as useless as it really is since motor topology affects the actual output as much as excursion does) is because people assume the bigger the Xmax, the louder the subwoofer. One reason power handling and power required is so high for a XXX sub is due to the XBL^2 motor. The sub is designed for sound quality, using stacked multiple small gaps in the magnetic field to maintain linearity at high excursions, so you keep a great BL curve across teh frequency spectrum for a sub, and the sub never leaves it's gap at high excursion the way conventional motor designs will, but you pay for that with poor efficiency needing more power, and reduced output even with it's high excursion.. The bright side is great linearity and a very accurate sub |
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thxrd Unregistered guest | yes, very good it is exactly my probleme because if it is really possible the RE XXX support 1600W real at very low frequency the thermical compression is very important (4 or 5 db)... and the real max SPL is reduce...so the real total linéar excursion is not really usable or very very few times before heating the voice coil and compression in fact the best spec is the real max SPL at low frequency ( between 30 at 100Hz pink noise 6 db crest factor by example) include the thermical compression... (normalised close enclosure at 0 ,707 spécific for each HP..) this test is included in AES test ... this test is very realistic because the max SPL is very very important (also other spec... of course.. but this spec is vital) what do yo think about 6174 Mc cauley (18") if you compare RE XXX (18") and 6174 for very low fréquency (15 to 60 hz)in your opinion which is the best...(not for SPL car audio but for my use.. and we suppose in each situation the perfect enclosure ..of course thank for your responses.. Roland |
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Silver Member Username: Lil_jonPost Number: 105 Registered: Jul-05 | GW is there 1 site that you created that i can install my 1st with? |
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thxrd Unregistered guest | you have a opinion or not??? if you want mail directly to me my mail is thxrd@club-internet.fr thank |
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