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I have blown 4 Black Widows when I ran PV speakers.     Lonman seems to think that they may have blown from being under powered.   This is a very viable condition for speaker damage, as is overpower.    This could be the case in the BWs.   But I have been running Yamahas for the past 14 years with out ever blowing one.   So I don't know the real cause for their failure.   I am considering a two amp system.   That was the reason for the "Amp Power" thread.     Still don't like the idea of having to use two different circuits, when most of the time they barely have one.  I have only ever tripped two breakers in 14 years.

Let's just say, i've only blown 1 18" sub that I was running on an 800 watt amp (bridged), this was a PV 18' Black Widow.  I replaced the basket & upgraded the amp to push 1450 watts & haven't had a problem since - 5 years now.  I'm not saying the Yamaha system is bad at all, I actually think it's a nice system, just know it'd sound much better bi-amp'd.

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I agree that it would make a sound difference, I just don't want to think about the hassle of two different circuits, in a one circuit bar.       I blew 4 in a year and a half.   After the last one I dumped them.    I bought another Yamaha set exactlly like the PVs.   Never had an issue with a blown speaker, again.

And that is wehre I disagree with him, I respect his opinion and experience, but it isn't under-poering the spekers that killed them, but over-driving the amp to the point of distortion. I am not saying that you aren't doing your job well, either, but that there is enough distortion from overdriving an amplifier to cause speaker damage in many cases, before the distortion is audible to human ears.  Careful watching of levels can prevent this from happening. If there si no clipping anywhere in th signal chain and the amplifier isn't being driven to the point of clipping, then there is no reason to thing a small amplifier will cause a big speaker to fail. Period.

 

I maintain that distortion was the culprit. You have  likely learned two things since then: 1.  I bet you watch  you levels more carefully, whether you realize it or not, and 2. you buy better speakers than you did 15 years ago.



Sorry to have strayed from the original topic, but I couldn't let it go. On the subject of bi-amping, once you do it, you will NEVER look back. I used to Bi-amp until someone stole my amps and speakers from a friends garage, several years ago.  In the interest of what I thought would be easier setup, I bought some JBLs with dual 15s and horns in each enclosure, thinking that it would be simpler than my old setup.  I was wrong.  The sound never approached the quality that I had before, and the speakers were heavy, bulky and clunky.

I have since retired the JBLs to storage and started bi-amping again. On a similar amount of power, I get better, smoother frequency response, in a little over half the weight and space.  My point is that if you add a single subwoofer and amplifier and keep your two amps and  crossover in the same rack, then the only extra setup required at each show is placing the subwoofer somewhere and running one more speaker cable.  TRUST me, it is well worth the extra effort.

While two circuits are a good idea, you CAN run 2 amps on 1 circuit.  You may not technically get the 'full' power out of the system, but chances are you aren't going to be pushing your system to the maximum either so you would run no chance of blowing a breaker.  I have 4 amps running on 1 20 amp circuit (but also ran the same system on 15 amp breakers with no probs as well) along with the rest of the system & a big screen TV since 2000 & never had a problem - in a '1 circuit bar' as you stated, chances are you wouldn't even need to bring the sub half of the system anyway so that 2nd amp wouldn't be needed nor would the sub.
Again, I said the Yamahas are a nice sytem, but are capable of so much more sound wise.

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Right but if the amp would have been of correct power to begin with (thus underpowered) the volume wouldn't have been turned up to the point of clipping - but yes you are correct on the overdriving of the amp, the amp was still too underpowered for the speaker in question to get the desired volume.

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I switched speakers, not the amp.   Bought the same setup from Yamaha.   I did nothing different other than speakers.    Ran at the same volumes and amp settings.   Added nor eliminated no other equipment.   Same cables, same amp, same mixer, same effects.    I don't remember the wattage rating for the Black Widows.   The yamahas are rated tops and bottoms 500 each with 1000 max.    I don't see how one set kept blowing and the other never has.

Most likely if your mains & your subs - the Peaveys - were Black Widow equipped (not knowing models can only speculate with standard BW ratings), the subs alone would have needed 1000 watts each by themselves at 8 ohms.  If your tops were also Black Widow equipped they would have required approx 750-1000 watts by themselves at 8 ohms.  When you put them both together in series they are now 4 ohms needed anywhere from 1750-2000 watts to be ran efficiently - thus you were probably overdriving the amp (underpowered for the set-up) as your Crown only pushes 900 watts into 4 ohms.  The Yamaha system you got now, the tops require about 500 watts, the subs require about 600 watts (both into 8 ohms) combine them together makes 4 ohms needing approx 1100 watts, your amp pushes 900 watts into 4 ohms, still a little underpowered - however a better match for the speaker system which is why you probably haven't blown them.

BTW I was double checking the specs on your subs & noticed they don't have a built in crossover in them, you are essentially trying to push a full range signal through them making them reproduce frequencies they are designed to do.  They should be crossed over somewhere around 90 hz & right now they are pushing frequencies up to 2000 hz interfering with the full range tops that are already reproducing those frequencies.  Which means your tops are also trying to reproduce the low frequencies as well - they are basically cancelling each other out.  Once you get the system crossed over properly, you will hear a dramatic increase in sound quality & sonic clarity.
You want the subs to only push the low frequencies & your tops to push the rest of the frequencies where the sub is crossed over at.

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