PRR-176 REV 4 Build Thread ***Manual up!***1/16/14 - (chk 1st post)

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Yes it was stereo link.
In fact, the switch isn't only for linking, is for unlinking too!

so: 2 channels are working, compressing.
when I engage filters, a lot of compression and you???

I think I won't use 470R pad... I have to do some tests

and the last mystery... in bypass a looooooooooooooow sound...

Guys, I think we could ask some royalties to Abe about selling this rev4 pcbs!!! ;D
 
"so: 2 channels are working, compressing.
when I engage filters, a lot of compression and you???"

yes it's normal
for me I think is
pos 1 (L) no HPF
pos 2 (C) desser
pos 3 (R) 200 HPF.

I will try a solution for low signal in Bypass mode....
 
I think you're right sorry...
but I 've done yet my front panel with "no hpf" in middle pos  :mad:
how can I mod this in the circuit...
 
I can't work out how the filters work.  I would have thought they would be simple RC filters, but I can't work out which R?
 
Filters seem to work with addition in sidechain:

deesser: 1n
no hpf: 100n+1n
200hz: 1n+1u/50V

can I leave 22p with DOAs?
 
Very low output with rolled off low frequencies = output tx secondary has only one end connected. Check your wiring to the next device and of course any internal wiring. I had this problem with another project many years a go and it turned out to be my interface having TRS input socket but the ring portion wasn't connected anywhere! Hope this helps debugging.
 
Hi
My unit is working but I've a same problem of REV 2
I've brought 2x matched pair of RCA 6BC8, but in stereo mode the channels are unmatched...
Tubes problem?
I never managed to find a pair of really matched 6BC8.... :-X
What alternatives do we have?
there are several 6n5p matched pair on Ebay
Can these tube work?
Thanks
 
ilfungo said:
Hi
My unit is working but I've a same problem of REV 2
I've brought 2x matched pair of RCA 6BC8, but in stereo mode the channels are unmatched...
Tubes problem?
I never managed to find a pair of really matched 6BC8.... :-X
What alternatives do we have?
there are several 6n5p matched pair on Ebay
Can these tube work?
Thanks

Great!
Did you tried r50/r103, trimmers for output symetry?
Did you found bypass problem?

I'm actually looking for why, on channel 2, it's working with ne5534 on output but not with DOA :mad:
Do you use DOAs?
 
Great!
Did you tried r50/r103, trimmers for output symetry?
Did you found bypass problem?

I'm actually looking for why, on channel 2, it's working with ne5534 on output but not with DOA :mad:
Do you use DOAs?
[/quote]


Hi mrdarwin
I'm using a transformer output option, No trimmers for simmetry...
The bypass problem is still there....
I'm using a doa on output and is working...

Hi e.oelberg
Also mine are very hot also with big dissipators, but no problem after 2 houers of work...
I want try with T03 version of regulator.

For you on stereo mode the channels are matched?
 
Anyone using the Don Audio power transformer?  I assume the 18VAC 1.2A secondary is used for the tube heaters.  Is the 18VAC 0.4A secondary adequate for the op-amps?
 

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