Official Epik Subwoofer Thread - Page 698 - AVS Forum | Home Theater Discussions And Reviews
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post #20911 of 20915 Old Today, 04:42 PM
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Originally Posted by daveds50 View Post
careful with that... that is a myth that someone made up a long time ago, that has been proven wrong over and over. sure, with too little power, some people without any self control will severely clip the amp and will overheat the voice coil. but it sounds like crap and they should have known better.

however, i can overheat the voice coil even faster overpowering, and often do so on purpose just for fun. no driver has lasted here more than 10 seconds at 29,000 watts true RMS. in fact, no driver so far has lasted more than 1 minute at 8,000 true RMS yet.

and then we could get into the concert stage amps that come here... they often do blow up the output stage due to frying the voice coils from raw power.
Its not a myth. I do acknowledge both are possible but FAR MORE people destroy drivers from exceeding the amplifier capability than by exceeding the driver capability. By the way, what's the dB level at 29,000 watt? 200dB?

I also said this in that post:

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Originally Posted by Dreamliner View Post
Honestly, unless your ears are bleeding, your not going to blow up your woofers, especially if you run your receiver calibration (Audyssey on Denon, for example). If you were on the verge of destroying your subs, you would hear it; hearing distortion from playing too loud with an under-powered amplifier or hearing distortion from over-exerting the drivers with too much power. To over-exert these drivers though, it would be seriously uncomfortably loud.
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post #20912 of 20915 Old Today, 05:18 PM
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Originally Posted by Dreamliner View Post
Its not a myth. I do acknowledge both are possible but FAR MORE people destroy drivers from exceeding the amplifier capability than by exceeding the driver capability. By the way, what's the dB level at 29,000 watt? 200dB?

I also said this in that post:
I won't be experimenting with this but I think you would bottom out the sub drivers producing a loud "BAM!". This could be destructive depending on the design of the voice coils.
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post #20913 of 20915 Old Today, 05:37 PM
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Its not a myth. I do acknowledge both are possible but FAR MORE people destroy drivers from exceeding the amplifier capability than by exceeding the driver capability. By the way, what's the dB level at 29,000 watt? 200dB?

I also said this in that post:
only 128dB before smoking. there is only so much that can be done with a single 12 inch 4000 watt driver. when it was in a van with sixteen 15 inch drivers it did 172dB. i did not own the van, but they were my amps... and i was nowhere near the van when they did that run. i have an insane amount of high end car and home audio equipment in my shop that i have been collecting since the mid 1970's.

when i first heard that myth, it was about 20 years ago. a person told me that when i was fixing his Marantz 100 watt x 2 amp. he was using some Seas midrange and tweeters that were rated at 70 watts RMS. ( and yes, they are crossovered perfectly, as verified by my oscilloscope ) i told him to check his speakers with a multimeter because the output section of the amp in one channel was toast. of course, he knew more than anyone in the world about audio and ignored me.

so after the amp was fixed, he hooked it up and immediately fried the same channel.

i went there to check his system and sure enough, one of the midranges was dead shorted. the voice coil was cooked.

so of course, he again did not listen, and replaced it with the exact same speaker.

one month later, the other channel blew out... the same damage.

so i actually gave him a set of 100 watt RMS Dynaudio speakers, and he has been using them for the last 20 years, with the same amp. i took his speakers, and replaced the bad one, and have been using them on my 1977 mid line Pioneer ( 45 watts x 2 ) that i have in my shop office since then too.

you may not think it is a myth, but i can give at least 50 examples with my customers that prove it is a myth.

but yes, clipping an amp is just as destructive. but at least i can hear the clipping before it happens.

there is actually a lot of audio myths... one "expert" in the past on a forum, tried to tell me one... about an amp that i was the sole engineer for.



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Originally Posted by Engineer99 View Post
I won't be experimenting with this but I think you would bottom out the sub drivers producing a loud "BAM!". This could be destructive depending on the design of the voice coils.
not this one though. specifically designed SPL driver that has at least 3 inches of travel before total mechanical limit. normal operation at 4000 watts RMS is 1.6 Xmax. i built the driver.
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post #20914 of 20915 Old Today, 05:47 PM
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Originally Posted by daveds50 View Post
only 128dB before smoking. there is only so much that can be done with a single 12 inch 4000 watt driver. when it was in a van with sixteen 15 inch drivers it did 172dB. i did not own the van, but they were my amps... and i was nowhere near the van when they did that run. i have an insane amount of high end car and home audio equipment in my shop that i have been collecting since the mid 1970's.



when i first heard that myth, it was about 20 years ago. a person told me that when i was fixing his Marantz 100 watt x 2 amp. he was using some Seas midrange and tweeters that were rated at 70 watts RMS. ( and yes, they are crossovered perfectly, as verified by my oscilloscope ) i told him to check his speakers with a multimeter because the output section of the amp in one channel was toast. of course, he knew more than anyone in the world about audio and ignored me.



so after the amp was fixed, he hooked it up and immediately fried the same channel.



i went there to check his system and sure enough, one of the midranges was dead shorted. the voice coil was cooked.



so of course, he again did not listen, and replaced it with the exact same speaker.



one month later, the other channel blew out... the same damage.



so i actually gave him a set of 100 watt RMS Dynaudio speakers, and he has been using them for the last 20 years, with the same amp. i took his speakers, and replaced the bad one, and have been using them on my 1977 mid line Pioneer ( 45 watts x 2 ) that i have in my shop office since then too.



you may not think it is a myth, but i can give at least 50 examples with my customers that prove it is a myth.



but yes, clipping an amp is just as destructive. but at least i can hear the clipping before it happens.



there is actually a lot of audio myths... one "expert" in the past on a forum, tried to tell me one... about an amp that i was the sole engineer for.











not this one though. specifically designed SPL driver that has at least 3 inches of travel before total mechanical limit. normal operation at 4000 watts RMS is 1.6 Xmax. i built the driver.
Your example seems to indicate matching drivers to amps but the actual output of amplifies often do not match their ratings (quality amps often exceeding their rating by a fairly large margin). How would you reconcile that in your example?

My point is simply this: if you don't distort, you won't fry it.

If you disagree, what would you recommend?
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post #20915 of 20915 Old Today, 06:58 PM
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Originally Posted by Dreamliner View Post
Your example seems to indicate matching drivers to amps but the actual output of amplifies often do not match their ratings (quality amps often exceeding their rating by a fairly large margin). How would you reconcile that in your example?

My point is simply this: if you don't distort, you won't fry it.

If you disagree, what would you recommend?
the Marantz amp is 100.46 right channel, 100.58 left channel. i still have the paperwork for that repair. for those amps that are known to measure higher than advertised, just get what matches close to what they actually do. the actual numbers are all out there. there are also a lot of upper end amps that are advertised as true spec... example, 147 watts x 2.

i dont tell people to match exactly. just do not vary by a whole lot. too overpowered and the voice coils will eventually overheat. too much under, and some people will clip the amp. both will destroy speakers.

distortion can be heard, clipping also, but it is not always apparent that a voice coil is overheating until it is too late. some speakers sound just fine with too much power until they dont. some amps are so clean, that you will have no idea that you are sending way more power than the speaker can handle.

ok, back on subject. i used to service pallets of iNuke amps... way more of them then i care to think about. while i was never interested in doing any actual tests on them, i do know that when compared to a real quality amp that i have tested, the iNukes were definitely weaker when they advertise the same power. but then again, the iNukes are 1/10th the price, so that is to be expected.

still, if going way over on the advertised power, best to be careful, and i would recommend not playing at a high level for extended periods. i cannot count how many speakers i have overheated when i burn in amps. ( you ought to hear my shop when 30 subs are pounding at the same time ) lets just say i take quite a load to the recycling center every month.
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