has anyone done a power increase on a power amp before without a bunch of headaches?? I have a old acoustic control model 400 I and rebuilding the preamp / biasing circuit boards for, the amp currently runs 110 VDC on it rails, the preamp/biasing design im and going to incorporate runs on 75 VDC, the transistors in both final stages and preamp stages will handle the increased voltage, I do know I have to make a change to 2 resistors for the power supply to my OP amp to run correctly. im concerned about the pre amp transistors biasing.. or am I just being a wuss?? any sugestions??
It's usually a bad idea. More voltage means more power, which means more transistors to handle that power, which means the driver stage needs to be stronger...
the output stage im using is from the unit that had the 110VDC power supply the preamp is the only difference.
is the 110Vdc a single polarity supply?
or
is it a dual +-110Vdc supply?
or
is it a split into dual +-55Vdc?
These three options are very different, as far as the amplifier design is concerned.
or
is it a dual +-110Vdc supply?
or
is it a split into dual +-55Vdc?
These three options are very different, as far as the amplifier design is concerned.
yes its a single 110V supply, meaning theres 110 VDC+ and - not 55V, this amp is 2 mono blocks in 1 case with 2 independent supplys. this amp has the supply it was born with, the transistors are the ones it was born with, they were running 110V before, in just changing the preamp/biasing section im borrowing from another amplifier design that runs 75VDC on its rails,the 75V amp uses identical output transistors and is a simpler circuit when it comes to the preamp circuit. I can lower the voltage to 75VDC and build this amplifier with no problem, I just wanted to try to use the 110VDC if I could for a little more power.
Just changing the pre amp part won't get you any more power.
The only reason I could think of from the info you have given, to change the pre amp part, is that the pre amp part that was in the 110V amp has blown. Is this the case?
The only reason I could think of from the info you have given, to change the pre amp part, is that the pre amp part that was in the 110V amp has blown. Is this the case?
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I know that.....l im not a dummy here... I am changing the preamp/ biasing section because the pre amp that was originally with this amp if VERY unstable and very noisy.. more power is not all I am after here, clean signal and reliability is.. i just wanted to use the power supply that was already installed in this unit. the preamp section I AM GOING TO BUILD is biased for 75VDC with its resistors now. thanks anyway...
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