Aleph 3 schematic

[thebiglebowski13]

Just bought a pair of Pass Aleph 3 amps (original not clone/copy) but they are noisy and need a recap.

Does anyone have a schematic or circuit design for them and maybe a recommendation for which cap model to use, was probably going to look at Clarity as I've used them before.

 

[Zen Mod]

caps - any brand name

you can bypass signal ones (small ones on channel pcbs) with nice solid cap (0u47-1u), piggybacking on copper side

best to open it, and measure what exact size you can squeeze in

 

[thebiglebowski13]

Thanks but I seem to have had a brain fart, I put 3 when I meant the Aleph 2

managed to find the service manual online so will have a read through that.

 

[Zen Mod]

Can't be Dude without Brainfart

 

[OnAudio]

All very nice amplifiers. Zen do you prefer XLR or RCA with them?

 

[Zen Mod]

Can't care less

 

[Dennis Hui]

@thebiglebowski13 : Congratulations on the Aleph 2! Aside from verifying dimensions as Zen Mod noted, I suggest looking for replacement caps with 105C rating. For the 220uF caps, Mr Pass had suggested the Elna Silmic as replacements. (They've been discontinued, though you might still find some available.)

 

[thebiglebowski13]

Yeah I was looking for 60+v and 105c but there doesn't seem to be many options, found Vishay on mouser but they are £40 each 😱

Will take it apart and double check but think they are 30mm wide with 10mm through board connections.

 

[Nelson Pass]

I look on Mouser and found some suitable caps.

https://www.mouser.com/c/passive-co...luminum-electrolytic-capacitors-snap-in|~Life

Most expensive is $9 Rubycon 15,000 uF 50V 3000 hours 105 deg C.

 

[thebiglebowski13]

cheers, is it ok to use 15000uF instead as the A2 (had a brain fart and posted the thread as A3 by mistake) schematic shows 22000uF?

 

[Zen Mod]

more, the merrier

Pa gave you minimal appropriate value

 

[OnAudio]

Can't care less

Thanks Zen, yeah I guess that's the usual response with some audiophiles. However for short quite home runs, RCA runs circles around XLR all day long especially for pure direct amplifiers. Mr. Pass(until he refutes😊) probably using RCA cause he didn't stumble across these designs and consistently stick to them without cause.

 

[OnAudio]

cheers, is it ok to use 15000uF instead as the A2 (had a brain fart and posted the thread as A3 by mistake) schematic shows 22000uF?

You probably want the rails as stiff as possible due to the mosfet input stage