Film caps in powersupplies

And a plain copper groundplates
I see!
1687029497190.png
 
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Motor run caps or any solid caps?
speaking of motor runs

100uF is pretty much same size as 50uF, while price isn't doubled

what I meant, just be sure we're on same page, if you think putting less than 50uF motor run caps, do not even bother

if you think of less than 50uF, feel free to use some in more convenient/nicer looking case, which also wouldn't invoke your audiofriends making fun of you

:clown:

me - I don't care - don't have audiofriends

of course, if you want ultimate, buy few '' of thin wall brass tube, put each of your motor-run caps in appropriate piece of tube, shiny it up, conceal solder lugs with some fancy wire, write Obligahaha on it, clear coat

you'll be main Boss

you can also use magic words as WE, Beeswax, Cotton, Virgin Pee

:devilr:
 
The moment I hear some hum I'll replace them. For now, they are dead quiet.
That's common sense.
I replaced mine as a precaution and those sizes (the ones I needed) are nowadays very hard to get or you have to order them in bulk (over 24 or so) or they are very expensive. So I saw an opportunity for a decent price and they were on stock so I bought them.
NP stated they if they service power amps they (recommend to) change the psu caps if they're older than 20 years. Mine were 35 years so I changed them but they're still good as you said.
 
Another thing is that's there no softstart circuit implemented in my SA/1.
I bought this thermistor:
1687037024460.png

Ametherm MS35 10 ohm 18 Amp Inrush Current Limiter to put where I always see CL60's in schematics of Aleph amplifiers.
Not for surpressing groundloops of course, but TH2 in this case.
1687037389899.png

These are thermistors too I believe in a SA/10/11M
1687037265206.png
 
When I changed the power supply (early on) I used a lower voltage transformer, the BC caps and hardwired them CRCRC. Another change was made by replacing the point to point circuit with a 'real' PCB and added a cover on top of the amps.View attachment 1184482
Looks very need and tidy especially for a DIY Aleph version..
Why did you choose those golden powerresistors with heatsinks? Do they become hot in a CRCRC implementation? Normally I see those in a softstart circuit.
 
powerresistors
They are 0,1 ohm 10W resistors and mounting them on the ground plate makes for a good heatsink. They get hot. The bridge rectifier is also mounted on that ground plate which adds up to the heat. Downside is that the caps absorb part of that heat. But they never complain..

Yes, that Threshold looks like new. What speakers are they driving now?
 
Downside is that the caps absorb part of that heat. But they never complain..
Haha, they wouldn't dare...

Yes, that Threshold looks like new. What speakers are they driving now?
Infinity QLS's. They don´t complain either about the load and low efficiency...

This user (https://www.diyaudio.com/community/threads/brand-new-threshold-sa-1-pair-from-1988.385741/) scored some NOS Threshold SA/1's, black fascia's also. These were really pristine.
 
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