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Old 23rd August 2011, 03:17 PM   #2261
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Where do you get the *2 from in your equation?

It'll draw about 200mA with 8 ohms speakers, so around 110 hours of expectable playing time. Remember that is 110 hours at maximum volume, more than enough for an entire festival.

The piezos you refer to are both crap but the QLM-1005 is the least shitty.
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Old 23rd August 2011, 03:40 PM   #2262
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from yours believe it's written on page 32 on the roskilde forum (http://roskilde-festival.dk/forum/mm...tereo/page/31/)

as long as it plays the entire festival

Last edited by Lars Jensen; 23rd August 2011 at 04:04 PM.
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Old 23rd August 2011, 03:42 PM   #2263
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from yours believe it's written on page 32 on the roskilde forum
Doubtful unless I calculated it for someone who had 2x 22aH batteries

EDIT: or as in this case where it was a car battery where the capacity is roughly 2/3rds, in which case you forgot the *2 is from the 2/3rds calculation

Last edited by Saturnus; 23rd August 2011 at 03:51 PM.
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Old 23rd August 2011, 04:04 PM   #2264
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EDIT: or as in this case where it was a car battery where the capacity is roughly 2/3rds, in which case you forgot the *2 is from the 2/3rds calculation
gotta see my calculations through apparentley, sorry about that one..

and what is the absolute most important thing in the piezo finding?

Last edited by Lars Jensen; 23rd August 2011 at 04:10 PM.
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Old 23rd August 2011, 04:51 PM   #2265
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and what is the absolute most important thing in the piezo finding?
Availability appearantly. All recommended piezos are not to be found on sale anywhere, so basically what you're left with is cheap Motorola/CTR replicas.

I neither have the time nor the willingness to listen my way through the sea of those in order to find some that might be half decent.

So pressume that they're all crap but given the directions herein on usage should be acceptable for the use.
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Old 23rd August 2011, 05:29 PM   #2266
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Originally Posted by Saturnus View Post
Availability appearantly. All recommended piezos are not to be found on sale anywhere, so basically what you're left with is cheap Motorola/CTR replicas.

I neither have the time nor the willingness to listen my way through the sea of those in order to find some that might be half decent.

So pressume that they're all crap but given the directions herein on usage should be acceptable for the use.
totally understand that you don't want to listen to litterally thousands of piezo's, think we'll go with the best of the crappy ones from the previous note, and then hope it works fine
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Old 24th August 2011, 06:56 AM   #2267
osny is offline osny  Sweden
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It seems to be an amp specific problem for the Lepai amp at around 75-80% of volume bass starts to disappear and treble gets nasty. Nothing you can do about that except for changing amp.

But it is a good idea to dampen the back side of the piezos.
Is this true?
And if, do you have the same problem?
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Old 24th August 2011, 08:11 AM   #2268
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I don't have a Lepai amp, so no, but the problem is described in the thread about the Lepai amp.
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Old 25th August 2011, 01:05 PM   #2269
ThokN is offline ThokN  Denmark
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Is this true?
And if, do you have the same problem?
It's true with mine, and also my friend's. We used it with the Monacor SP-60/4's and not HP-10W, so don't know if that's the reason.

AFAIK, PressureFM, also at this board, build a typical boominator with the Lepai, and sounded fine as I remember, but he knows.
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Old 25th August 2011, 01:14 PM   #2270
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It's true with mine, and also my friend's. We used it with the Monacor SP-60/4's and not HP-10W, so don't know if that's the reason.

AFAIK, PressureFM, also at this board, build a typical boominator with the Lepai, and sounded fine as I remember, but he knows.
It does crap out at around 75% and distort like crazy but the pre-amp and other components in the Lepai is subpar to begin with. The pre-amp chip is not even "qualified" to be used for music but you can read more about it in the Lepai thread. Better off grabbing the AMP6B I suppose. I had both the Lepai and AMP6B at Roskilde though. Always good to have a backup, especially when someone spills soap-bubble water all over your Boominator

However I'm using real tweeters and not piezo's.
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