SissySIT R.3

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"Don't let more dust gather."
Tell that to Mighty ZM! : P
(Greedy boyz be greedy)

Very interested in hearing your thoughts afterward. If I had a separate box for the PSU, a CLC would be my go-to. But, shoving them into the same chassis is challenging due to the extra stray magnetic flux caused from all that iron.

I believe there was another member building a SissySIT R.3 with one of Sami's SMPS. I'm curious if they ever wrapped it up...
 
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The MicroAudio SMPS is one of the few supplies that I haven’t tried yet. I also am planning to build an XA252, and haven’t ordered the big toroidal transformers yet. Hmmm..

My latest (re-)build of the supply in my M2x is a dual-mono CLC. I bypassed the inductors with resistors to control the Q factor and lower the impedance between the capacitor banks (less voltage drop). The L was Hammond 154B bypassed with 2.2 Ohms.
I was very pleased with the result.
 
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Nothing to see here... And I'm certainly not working on a more sinister version of my front end...:Popworm: :devilish::hot:
 

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Some progress, albeit slow. First channel nearly complete of my FE update project. I'm experimenting with the compensation values and method now. I know enough to be dangerous but I'm still a greenhorn in this arena. I've had my nose buried in Mr. Cordell's book, not fully understanding everything but some of the material is sticking. The circuit is looking pretty good, I think.. This is with 24V rails, 600 ohm / 1000 pF load. Gain is 6x. There is some rail sticking when it clips, but I can't imagine I will be bumping into that in use. So I probably won't worry about throwing more parts at it to fix that issue. There is a small bump on the leading edge of the square wave when I zoom in on the trace. Not sure if that's really a problem or not. Still trying to learn about this stuff. Had lots of overshoot on first power-up, but it was very stable otherwise. Miller cap is 33pF. A 4.7pF lead capacitor across the FB resistor squashed the overshoot, almost completely. Threw lots of tricks at this one... B. Hofer style feedback - 5 ppm resistor string, Darlington VAS, input degeneration, optimized grounds and pcb track decoupling, ground loop breaker, stock Stasis twice regulated bias voltage thing.. but IPS CCS gets it's own 3*Vbe drop.. 2nd and 3rd stage CCS bias voltage are shared from an HLMP-6000 LED. And a few other small tricks not mentioned. Maybe most of it doesn't really matter.. I'm just having fun with an audio hobby here..
 

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"What is the point of all this William? Why spend the time, money, and effort with a do-over? I thought you said it was pretty good already?...."

The goal was to improve the treble performance, the top couple of octaves. My previous FE was tombo's excellent input stage with super low distortion and perfect xformer coupling. The upper mids and treble performance of the "Blasphemy" were a big step up from my other attempts, subjectively, and kinda eye-opening. The midrange is fantastic with this Stasis FE, relaxed but very detailed, no fatigue and no complaints, but I wanted to see if the upper range could be improved. So, the story continues.. now to finish up channel #2 and see what happens...
 
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