the sound of bad caps

Hi there:

I can find all sorts of examples of how bad caps *look*, but does anyone have any good descriptions (or audio examples) of what failing capacitors *sound* like? 

Thanks,
David

That all depends on what the capacitor is supposed to do in the circuit.

The things I have discovered so far:

Bad caps in the power supply: Output signal gets distorted due to low voltage in the circuit
Bad filter caps: lower signal or no signal at all, less bass in output signal

Bad filter caps in PSU,  60 cycle hum in US

Most common failure is loss of electrolyte so a completely gone cap will not pass signal at all. A partially gone cap, could act like a smaller value cap, so lose LF content.

There is whole wing of the golden ear institute dedicated to how capacitors sound bad, but I didn't matriculate there and never will.

Broken or failing capacitors can add distortion, and any number of artifacts. while generally the failures are graceful and incremental over time.

JR

jstark said:

Hi there:

I can find all sorts of examples of how bad caps *look*, but does anyone have any good descriptions (or audio examples) of what failing capacitors *sound* like? 

Click to expand...

To add to the excellent answers already provided, one thing to check is input and output DC blocking caps. If they are run with an applied bias that exceeds ratings for "too long," the parts will lose capacity. In this scenario, the LF cutoff point goes up as capacitance decreases.

-a

while generally the failures are graceful and incremental over time.

Click to expand...

i guess this is the answer i expected--that there is no obvious Sound Of A Bad Capacitor.

the loss of LF makes sense, too.

i suppose I'll recap channel 1 and see how it compares to channel 2.

thanks, guys.  so helpful.

peace.
david.