Aleph power supply capacitors considerations

[zygibajt]

What brand of those big cans do you usually use?
What are the individual sonic characters of diffrent PS caps?

As I recall Mr Nelson uses Mallory caps.
I cosider Siemens,Panasonic and Aerovox to be among the best,but which of them to choose? I don't know.

Would like to hear your opinions on that topic.
Any one ever compare diffrent brands of caps and their sound?

Bartek

[Nelson Pass]

I use what's reliable and reasonable, and keeping in mind
that most of these are made by the same plants, it's not
suprising that they tend to sound about the same, all other
things being equal.

Lots of capacitance and CLC or CRC type filtration really helps,
and depending on the circuit, some good film bypass can really
help - and almost never hurts.

[zygibajt]

Thanks for the answer Mr Pass.

some good film bypass can really help

That is what I observed with Aleph 4 and Alep 3 clones.It really betters the sound.
But I also observed that putting small caps across rectifire diodes kills the sound.

As to the capacitance:
Do you think building up those high capacitances with smaller values (like ten 10000uF caps instead of four 25000uF) might improve things?

Bartek

[chrisx]

Hi,
I'm preparing to build Aleph 2 monoblocks - my first serious diy audio project, so I have many questions. I will be glad to receive some help...
I'm completing order list for Aleph 2 PSU, so I need advice.
What capacitance amount should I use. In oryginal Aleph 2 scheme there are four 22 000 uF capacitors used, but at [URL=http://www.web.vip.hr/pcb-design.vip/power-2.html ] there is 8 times 47 000 uF used. I guess, bigger capacitance sounds better, but is there good compromise? Is it good to use many 10 000 uF (I can buy them cheap) instead of bigger ones? For my example 40 times 10 000 uF seems to be a little crazy idea.
One more question (little bit off topic): Is 600VA/40V trafo suitable for Aleph 2?

[jarek]

My observation is that a big value of capacitance and very small amount of ESR after a bridge can cause big distortion on sine wave on the secondary due to summary impedance of the secondary and diodes. Would be correct to use ordinary (not very low ESR) capacitors next to the bridge and only after filters (CRC or CLC) better capacitors with small ESR?

[markp]

It is better and much cheaper to use multiple smaller caps than a few really large ones. A slew of 4x4700s is better than one 22000 by a long shot, lower ESR and higher ripple current. I like to put a cap right next to each output transistor if possible with a film bypass cap.

[Angel Puerto]

I have put 4X150.000 uF bypass with 9x2.200uF/63V URZA type of Nipon Chemicon, the results were fantastic.
Onother probes with small capacitors in concret 0.1 and 10 uf film I did not the previus results.

Angel

[KBK]

In my personal experience, the bypass caps can create resonant circuits that create minute disortions that are passed on to the output stage and can -and usually are- mistaken to be treble and spatial information when all it really is.....is accentuated distortion.

The larger value the bypass cap, the better. The lower the number of bypass caps, the better. None is best. The idea of what capacitors to use must be re-addressed from the ground up. Then we might get somewhere, but also.. then.. the idea of how to implement a circuit must again be re-addressed from the ground up. Clean slate.

Careful control over the impedance in the pathways involving the bypass caps is critical to avoiding distortion created by the resonant circuit that WILL be in effect somewhere in that large 'dynamically changing' impedance that all audio bandwidth circuts encompass. It always happens... every time. Most folks cannot recognize it as such, because the rest of the situation must be cleared up to see that.. and that is a gargantuan enterprise, ivolving everything from the 120AC, all the way up to the room and your ears.

It can even take years to tune a single system to sound right. By that time, it's so sensitive to change -and showing the effects of change- that heisenberg seems to be at play.......

All I know is I will NEVER put a bypass cap in any piece of gear again. The sense of overall harmonic integrety that is achieved without such caps in the pathway (after much hard work!).... well it is so great to hear... so natural.. so easy to listen to... so relaxing...that I am sure you will agree as well.

But first, you must conquer that gargantuan task......

[zygibajt]

Great to hear your view,thanks.

Bartek

[Peter Daniel]

I share a similar POV (and observations): I will never add bypass cap again (unless in a digital circuit) as well. What initially seems like an improvement, eventually appears as smearing, coloration and artificiality.

Find a good cap and forget about bypasses.