Try an in line attenuator.... worked for me and here's the link.
http://www.diyaudio.com/forums/showthread.php?postid=547614#post547614
http://www.diyaudio.com/forums/showthread.php?postid=547614#post547614
Bridged lm3886 with 13 voltage gaincarlosfm said:Do you know the gain of the preamp?
What gain does your power amp have?
preamp has a gain of 2 its the opa2134 with buf634 3k in feedback and 2.k resistor from feedback to ground.
rabbitz said:Try an in line attenuator.... worked for me and here's the link.
Thanks I used that idea a few times
jaudio said:Bridged lm3886 with 13 voltage gain
Change it for 10x gain per chip.
jaudio said:preamp has a gain of 2 its the opa2134 with buf634 3k in feedback and 2.k resistor from feedback to ground.
That's 2.5x gain.
Sorry I meant 2.7k instead of 2kcarlosfm said:
Change it for 10x gain per chip.
That's 2.5x gain.
I really dont want to do that because I will have to change resistors for 20 chips.
I will remove the resistors from feedback and feedback to ground in the opa2134 and buf634 preamp then replace it with wire.
Do you see any problems?
jaudio said:I really dont want to do that because I will have to change resistors for 20 chips.
Anyway, you have a higher than normal gain for a power amp.
It's your choice, but keeping things this way means that you are not going to be able to connect any "standard" preamp to your power amps.
jaudio said:I will remove the resistors from feedback and feedback to ground in the opa2134 and buf634 preamp then replace it with wire.
Do you see any problems?
Change the 2.7k resistor for 5.6k, that should be enough (~1.5x) , I think you don't need to go unity-gain.
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