Aleph 5 power supply.

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I am building and Aleph 5 and I am wanting to use the power supply as shown at and I want to only use the first capacitor section of this supply, the 4 X 47,000uf portion.

Besides a higher ripple is there any reason why I can not use this section only? Or is it worth the extra expense and complexity to build the complete power supply?

And while I am on this subject what about building the front section only but using the inductor as well?

Thanks for any comments.

Tony D.
well Nelson, you must say that on your Aleph service manual U used only Caps, no coils, and if thats good for you I guess Its good for me ;)

I'm going to use only 2X47kuF/ch and a small 4uF polyester cap in paralell with each big capacitor to reduce the cap inductance as many of the guys do.

I don't know if it is ok, but I think I read something written by NP about this subject, don't know where :(

please correct me if I'm wrong before I kill the PSU, hehe
Just a follow up question regarding this power supply, on the weekend I bought a pair of Solen 3.9uf inductors in 16 guage.

Would there be any reason why these would not substitute for the 2uf inductors that Nelson has suggested?

I bought the 3.9's for $2. each and would like to use them if possible as the cost effectiveness is there.

Thanks for any info.

Tony D.
Capacitor Ripple Current

Nelson states that you should have a riplle current rating of 3 times the current draw.

I have some computer grade reservoir capacitors of 58,000uf, but i don't know the ripple current rating and have no manufacturers data.

Is there any way of measuring and/or calculating the ripple curent if it is not known?
aaah....the crash and burn method =) very effective... I guess you could check if the caps are hot to the touch or atleast "un naturaly warm" when in use that would most likely be a warning sign..

btw...i must question those supplyes why do one chose to put the larger capacitance before the inductor? and a smaler one after? ... to me it would be better to do the otherway around.. a bit lower current draw on start up a larger energy reservoar availibly to the amp (not isolated by inductor dcr) the inductor sees more ripple so it gets more work done...

why place the larger capacitance first??

The one and only
Joined 2001
Paid Member
The importance in size of the first cap is a function of
the ripple current and ripple voltage. If you have too
small a cap, both ripples will give you headaches.

On the second cap of a pi filter, large size contributes
to low noise and instantly available current. You don't
want to skimp here, either.

In practice, I just assign equal values on both sides and
ramble on to the next problem.

(Steve Martin Ramblin' Guy Icon)
But then again an inductor needs to have ripple across it to function?

I didnt mean to have an osurdly small cap first but like 50% of the last one. and not the otherway around.

I did some simulations of using a 1µF cap first... (in a CLCLCLC filter ) and as i recall it was better to use only CLCLC with equal values. so i guess that agreass with what you are saying.

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