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Scott R75s rebuild questions

So phase one of the restoration on my R75S is done. I should have taken a "before picture" so you could see how bad it looked when I brought it home. The tinted plexiglass piece was unglued and floating around. There were NO dial lights working, The wooden sides looked like they had survived a war. The front and top were filthy, and had tape and tape gum stuck on it in random locations. Some of the push button switches were pushed in and frozen.

What was done:
1) I disassembled the face plate and washed it. After cleaning it up as well as I could, I gave it a sealer coat of semi gloss lacquer to ensure the durability of the finish and lettering.
2) Cleaned and re-glued the plexiglass dial face.
3) The finish on the top was stripped off completely, then cleaned and re-coated with semi gloss lacquer. You will notice there is a slight color difference from the face.
4) Sides were removed and refinished. The left side had most of its original veneer so I just touched up with some custom colored wood putty to fill the small chipped areas. The right side panel was a mess as it was missing veneer on top and front. I pulled out my bag of veneer scraps and found a suitable walnut to use to re-veneer the missing parts. After sanding, I gave both sides three coats of Minwax Tung oil.
5) All switches and pots were cleaned with DeOxit D5 then lubricated with CRC 2-26 dry electrical lubricant.
6) Dial lamps replaced with new bulbs.

And this is what it looks like now...
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I just ordered an active vacuum desoldering tool and will be starting an order for this receiver soon. I was wondering what part you used accomplish the soft start. If possible, could you provide me with a part number and where you got it? I noticed a big low frequency transient when I turned on the amp with the speakers hooked up. I'm hoping this will help reduce the start up transient. Thanks!
 
I didn't build a soft-start circuit, but used this triac mod:
https://audiokarma.org/forums/index...orth-5-and-an-hour-or-so-of-your-time.504673/
I used: Q6040J7TP bc it was what was in stock. I think there are others that are more commonly used in that thread.
It's just a solid state switch to save the contacts of the original. Not sure it was necessary.

Mine has that big transient thump at startup as well--even after the triac mod. My theory, which I haven't yet tested, is that it's caused by asymmetry of capacitance on the rails caused by the local filter caps on each of the daughter boards which are all on the positive rail giving it north of 3000uf more to charge up so the negative rail comes up to power more quickly.

Edit: I see I mentioned "transient demand" above. Just referring to peak in music. Not this startup thump.
 
I'm returning to this receiver to address some hiss issues that I noticed when I switched a Pioneer SX-550 that I'm repairing into my system. It's noise floor is notably lower and it's not nearly as well-built as this Scott, but a decade later, the resistors are all carbon film, with metal oxide for the mid-watt locations.

Most of the Scott's resistors are carbon film: all of the tone board, preamp and radio circuits are carbon film. But, there are several carbon comp resistors on the driver boards for the 1/2W resistors (circled in red here). I'm planning on replacing those with metal film.

Advice I'm seeking:
1. Do any of the other resistors on the schematic (which are currently carbon film) look crucial for replacement to lower the hiss? What about the power transistor emitter resistors?

2. Do any of those transistors stand out as a concern?


Thanks again, as always!

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