Dual Ruby Problem

[RDV]

I'm running a second Ruby without the buffer section. One input to original board to JFET buffer, then where the out from the volume pot(from buffer to pin 2 on chip) is I have a wire from pin 2 of the other 386 to make a dual mono Ruby with both channels running individual speakers from the same buffer/cap/volume pot.

Now that you're perhaps very confused, this is my problem; it works, but one of the amps has a buzz that is part the sound when you're playing. A sort of flatulent flutter that sounds a bit like transistor mis-biasing, though it can't be that. I'm suspicious of the 220uF on the output of the second 386. Could a bad electro cause that sort of farty/fluttery sound?

I have tried different 386s and different ways of hooking the two together and it still happens & it's driving me to distraction. I simply have got to go to bed so I can go to work in the morning.

Could a fella get a couple of opinions? Please?

Thanks!

RDV

Goodnight

[Travis]

I breadboarded the Ruby last night, and had the same results you described when I removed the buffer.  I was using a REALLY low output single coil, and assumed that was the problem.  With even a slight boost in signal before the unbuffered Ruby the problem went away.

[RDV]

But I'm going into the 2nd Ruby with the volume control which is coming off the buffer. The first one sounds fine, which to me means(since it does it with different 386s) that perhaps there is a problem with the 220uF outcap. I gonna replace it when I get home.

Regards

RDV

[RDV]

It wasn't the 220uF cap. It was fine.

When I decided to put 2 Rubys in one box, I brought the other board back from the dead using solder braid to clean it up so I could re-solder everything. Well, I resoldered everything real nice, but forgot to tie pins 3 & 4 back together. DOH! The untied inverted input was the noise culprit, and that's that. YAWN!

Regards

RDV(cheap cap boy)