SissySIT

I'm getting around to building my R1 SissySIT, however my current (Abbas Audio) DACs have hot outputs, around 4.5 Vrms (according to Mr. Abbas, i have not measured them), and i'd rather not throw most of the signal away by attenuation. Unsure of the output impedance of the DACs, i will try to find out (tube buffers on output). I guess i could wire the autoformer differently to lower the gain, very grateful for any suggestions.
I have the same Abbas OPS and have you ever measured it’s output? I’ve never seen more than a couple to 2.5VAC with actual music.
 
In context, I hope it was clear that I meant replacing something else with Keratherm , after getting it

I did bought 86/82 from Conrad, several times

again, for clarity sake - Keratherm is best , if you have torque thingie , so that way being able to avoid overcompressing it ( screw side going down comparing to pin side of mosfet case)

if you don't have torque thingie, use Al Oxide pads with good (data is necessary, so no name ) goop

if not having any of these , use mica + good goop
 
I have gifts from behind the iron curtain….with HA optionals! Nice, very complete gift!


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I'm sure it has been asked 1000 times, but is it reasonable to bias Sissy at 2,1X A in negative rail?
My 4U 400 "9140" sinks are definitely hot, but not unbearably so (mounted on Keratherm).
No thermal runaway, but bias is still rising a bit after 60-90 minutes.
 
A friend of mine got a used R.2 version which I need to connect with an active front end instead of its buffer and trafo(so I need to disable this part).
I searched for the schematic but wasn’t able to find it..
Can anyone share a link with it?
Thanks.

There are a few caps here and there that are not soldered so a general inspection and cleaning would be a must even if the previous owner used the amp like this.
 

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