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Will hookig up only 2 channels on a 3 amp hurt the

Hi every one, another rookie question from yours truly, I have a dbx BX-3 power amp which can be ran in 2, 3, or 4 channel configurations. I'm using the amp for my main speakers, and have the inputs connected to my Yamaha receiver. I've attempted to place the amp in a 2 channel configuration for more power as the manual show's,
but I get a slit buzzing sound from the left speaker when I do this. To get rid of the buzzing sound, I've used the 3 channel configuration, but without a center channel. That's still running through my receiver. I hope I'm making myself clear. So, to my quesion. Could it hurt my main speakers by using the 3 channel configuration with out the bridged 3rd channel? Remeber, I'm a rookie
so please be nice.:)
dbx

Showing 2 responses by sean

sean
6,231 posts
 
There is no problem with doing what you are doing in terms of leaving a channel "dead".

Since i am not familiar with this amp ( have seen one but never used or read about them ), when you go into two channel mode, are you bridging the four channels down to two or just selecting two and leaving the other two dead ?

Out of curiosity, where did you purchase this amp from ? The place that i saw this amp at had told me that one of the channels had a hum or buzz in it, so this could either be the same amp or it might be a common problem to that piece of gear. Sean
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sean
6,231 posts
 
You might have something defective in one channel that is "out of balance" with the other channel that it is being bridged with. As such, have you tried running all four of the channels individually ? You can do this one at a time, two at a time, all four, etc... What i'm trying to find out is if they all work fine independently, then there is something wrong either in the bridging circuitry or one of the channels is out of "balance" with the other one. As far as "balancing", it could simply be a matter of a loose screw or ground inside the amp. It could also be something as complex as a few transistors that have "gone soft". If that is the case, it would need professional help.

Have you tried running it as a three channel amp yet and checked each of those three channels ? It is possible that the bridging configuration between the two and three channel modes ties the individual channels together in a different manner. This might solve your problem and the amp would work fine. You could also just use two out of the four channels as you would normally unless you need at least one high power channel ( like for a sub, etc... ). Sean
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