Power supply caps

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If I have the same voltage and uf values does it matter if I use 24x 10,000uf caps or 8x 30,000uf caps in a power supply. As I increase the number of caps there do I increase the distortion. If one alternative is better than the other which one would that be? Thanks.

Rob
 
Other points.

More capacitors takes up more room on the PCB, but are usually shorter. This might allow you to place two PS boards in the enclosure, one above the other, and still leave enough room for ventilation.

More capacitors gives more components to fail. But, as tsz pointed out, the ripple current per capacitor should be lower (or the bank can handle more ripple current), which should increase the life of the capacitor.

The capacitor bank with more capacitors would probably have a lower ESR and ESI (ESL?), along with a higher ripple current (I think these are related). The rest of the points are byproducts of this.

There would be lower HF residual noise with more capacitors.

The output voltage may be slightly higher with more capacitors. This would be because the impedance seen by the charging pulse (from the rectifier assembly) would be slightly lower.

The capacitor bank with more capacitors would be more able to deliver HUGE current spikes to the output devices. This usually only has a major effect in Class-AB amplifiers.

If you're going to all the trouble to use this many capacitors (either 8 or 24 in a bank), please put them on a PCB with thick (2-4 oz.) copper, and use wide traces. This will give you more of the improvement you're paying for.

Good luck.
 
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