I get rising resistance too. At a point I could measure 1,3,5 is around 12,7M; 12.6M; 40M; when tested from pins to heatsink screws. GND to metal case is not conected yet. Is that normal?
The second channel is mounted on the heatsink and giving same measurements. 1,3,5 pins not an infinite resitance to heastink. Pin 3 starting from around 500R and mounting. Is that OK?
Siberia, are the bolts for T5, T6 isolated from PCB (you inserted plastic washer) or they touches their pads on PCB (connected to GND)?
How about your VSSA at the moment? Is it connected according grounding schematic? Working?
Provided plastic washers are taking place between T5, T6 and the bottom of PCB. The bolt heads are touching PCB from the top side without any insulation.
Module ground is not connected to a case/earth point just yet. I was questioning my washer or MOSFET mounting technique before moving to gounding. Although, I would appreciate directions on how to implement 3 way grounding (speakers GND, earth and PSU GND) on one faston connector.
Is anyone here who will orders FineGolds to Mouser and willing to help me with a set of capacitors for VSSA ? Thanks !
OK, please follow VSSA Installation instructions for mosfet and all other transistors assembly. In any case 22 Ohm protection resistors in calibration phase will protect the VSSA if something not in order.
Grounding schematic and its stated corrections is 100% tested in three metal case assemblies up to now. It is dead quiet on speakers membranes also no mechanical hum from amplifier itself, made for late night easy listening too.
I was following your provided instructions with care. Just felt weird having continuity on the mosfets to heatsink. So if it's a green llight I'l proceed to adjusting with my 35V unregulated PSU. I'm waiting for my second DMM to arrive. But maybe with a bit of luck I could adjust it only with one DMM. Wish me luck. 
Calling sng001, PMI, miksi and all others to show current results on VSSA modules assembly. Is anyone there already made a working amplifier base on VSSA? 
Now I have a new excuse: I am waiting for the case 😀
Anyway, still struggling with the JC-80, that together with the truly excellent Paradise will give some nice food for VSSA 😉
Anyway, still struggling with the JC-80, that together with the truly excellent Paradise will give some nice food for VSSA 😉
Working on it...Calling sng001, PMI, miksi and all others to show current results on VSSA modules assembly. Is anyone there already made a working amplifier base on VSSA?
Calling sng001, PMI, miksi and all others to show current results on VSSA modules assembly. Is anyone there already made a working amplifier base on VSSA?
I'm not at home at the moment but yesterday I've replaced R19 and R20 with 1206 combo- 4x10 ohm, R23 was very difficult to remove so it's just piggybacked with 1206 zero ohm 'resistor'. Grounding finished as in schematic given earlier. Both channels turned on for about hour (everything was OK). Later afternoon, when I get home I will check whether hum problem was resolved when in audio chain, or not.
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Look to my SSA thread's final schematic (signature link bellow) and see what you need to do to use bipolar outputs. You cannot just replace laterals with bipolars, it would simply not "drink the water".
Sorry again for small off topic.
It is ''drinking the water'' in really amazing way.
I putted BJT toshiba drivers and outputs + little mod. Thanks LC for vssa again.
I did some pulse response test and must say that I have never had so quick bjt amp ever.
