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Quality capacitors which aren't low ESR?

Mike P

Mike P

Trade: Pickwell Audio
Can anyone here recommend a make and series of radial electrolytic capacitors which are good quality, i.e. long life and don't sound terrible but are not low ESR?

Most modern capacitors from quality manufacturers tend to be low ESR nowadays and sometimes you want a higher ESR cap (e.g. at the output of a voltage reg).

I know Robert used to recommend the old Elna Starget series forthis and I've had good results with Duroex myself but as far as I know both these series are discontinued now.

Cheers, Mike
 
It stands for equivalent series resistance, so why can't you add a series resistance? I don't follow this world of regulator guff in the background of pfm.
 
Most standard electrolytics have sufficient ESR for regulator stability. Just beware of specifically low ESR types and ceramics
 
Of course you can add series resistance but if you are doing a recap job it's easier if you can just drop in a suitable replacement part without having to mess about with adding an extra resistor in series.
 
davidsrsb said:
Most standard electrolytics have sufficient ESR for regulator stability. Just beware of specifically low ESR types and ceramics
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The series I most often use are Pansonic FC, FM, and Rubycon ZLH.

I've read some specific examples of Panasonic FC causing stability issues when used after regs and I believe I'm right in saying that the FM and ZLH are generally even lower ESR than the FC. It would be handy to have a small stock of higher ESR caps to hand for this so if anyone can recommend a series they use it'll save me having to trawl through the datasheets.
 
Japanese caps are best... you could also try some Nippon ChemiCon KMG.

My old Krell KRC3 preamp used these extensively. I was going to recap it a while back, but ended up not bothering as they were within spec, no bulging or leaks, and had been running always-on (high bias Class A) with no issues.
 
Yomanze said:
Japanese caps are best... you could also try some Nippon ChemiCon KMG.

My old Krell KRC3 preamp used these extensively. I was going to recap it a while back, but ended up not bothering as they were within spec, no bulging or leaks, and had been running always-on (high bias Class A) with no issues.
Click to expand...

I had a Krell integrated in which the owner had left on 24/7 after reading bollox on forums... Every electrolytic had failed other than, strangely, the main smoothing caps... which I replaced anyway as they were out of spec even though still working. Most of the electrolytics were showing around 10-20 Ohms ESR!! Still non had leaked or looked bad by eye.
 
Mike P said:
Of course you can add series resistance.........................
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No you cannot. This is another classic example of a little knowledge being a dangerous thing, it leads to countless myths about cap's in particular.

Low ESR tends to be the Holy Grail because low ESR means low losses due to heat, amongst other things. As for just adding a resistor - ESR of a cap' changes with frequency, the R of a resistor by and large, does not (although that too depends on the construction details of the resistor).

Want "high" ESR - use a smaller case-size at any given rating - ESR drops with increasing capacitive element size.
 
Yes you can. We're not concerned with change in ESR with frequency to any great extent here. In the case of this particular reg it ain't that critical anyway. The OP can add 0R47 if he's really bothered..
 
Arkless Electronics said:
I had a Krell integrated in which the owner had left on 24/7 after reading bollox on forums... Every electrolytic had failed other than, strangely, the main smoothing caps... which I replaced anyway as they were out of spec even though still working. Most of the electrolytics were showing around 10-20 Ohms ESR!! Still non had leaked or looked bad by eye.
Click to expand...

The KRC-3 didn’t even have a power switch. Am guessing too that it’s nowhere near as high current as the power amps...
 
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