What goes in, comes out.

Is this amp OK?
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Tom Smit
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What goes in, comes out.

#1 Post by Tom Smit »

I just recently hooked up a Behringer EP4000, sent 30hz into the board, maxed the channel, maxed the main out into the DCX2496 and measured the voltage coming out of the EP4000 (no cab hooked up). The voltage was 117v. I set the limiter to 50v for the LAB12 inside the T60.
I haven't looked into why the voltage got that high. Any comments?
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Radian
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Re: What goes in, comes out.

#2 Post by Radian »

117V ....that's peppy! :twisted:

Bridge mode maybe? Check the the DIP switches on the back panel. 6&7 should normally be set to "off".
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Bill Fitzmaurice
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Re: What goes in, comes out.

#3 Post by Bill Fitzmaurice »

Radian wrote:117V ....that's peppy! :twisted:

Bridge mode maybe? Check the the DIP switches on the back panel. 6&7 should normally be set to "off".
Either that or the amp is blown and you were reading the voltage out of the wall. An amp capable of 117v would have to be rated for 1700 watts into 8 ohms.

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Tom Smit
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Re: What goes in, comes out.

#4 Post by Tom Smit »

Nope, not bridged. And not blown. I got to listen to the T60 afterwards (utilizing only one channel for it) and everything worked well.

EP4000 is claimed to put out 4000 watts, peak, bridged. Or 2400 watts RMS, 1khz, bridged. At 8 ohms, it's more like 550 per channel.
TomS

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Bill Fitzmaurice
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Re: What goes in, comes out.

#5 Post by Bill Fitzmaurice »

Tom Smit wrote: At 8 ohms, it's more like 550 per channel.
The most you should read is 66v ch. You must have it bridged, don't do that.

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Tom Smit
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Re: What goes in, comes out.

#6 Post by Tom Smit »

Bill Fitzmaurice wrote:
Tom Smit wrote: At 8 ohms, it's more like 550 per channel.
The most you should read is 66v ch. You must have it bridged, don't do that.
I just read this and thought, Nope, wasn't bridged at all. I took one wire off the binding post (channel 2)which was going to the sub. I plugged and NL2-with-pigtail into a Speakon jack on channel 2 and measured that pigtail voltage.
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Rune Bivrin
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Re: What goes in, comes out.

#7 Post by Rune Bivrin »

There's always the possibility of a busted DVM. Although it's a fairly unusual failure mode, unless it's simply the battery that's flat.

Or with every gain knob maxed you had clipping, and the DVM is misinterpreting what it gets at 30Hz. Most cheap DVM:s are calibrated to assume sine at 50-60Hz.
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Re: What goes in, comes out.

#8 Post by 88h88 »

I had similar fun with a QSC GX5 which managed to somehow output well over 100v. This was great fun whilst trying to set my limiter as no matter what I did, the voltage was enough to fry my drivers. Turns out my friend had for some reason decided to test the mains voltage with it and managed to fry the internals...

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New meter and I was back in the game.
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