Using used capacitors?

I have a Bose amp to fix (car), which in this case means changing out the electrolytic capacitors, as bose used a bunch of not quite sealed ones way back when. So the question is: can I just use the ones I can salvage from all the various boards I've collected, or do they need to be the same brand/grade whatever? I know about polarity and rating (i can reed!?) and can solder/desolder pretty well. I know that there may be other prob's, though the capacitor issue was well known & documented on the web. Thanks to all who help out.

orksecurity8 years ago
If it is the same type (electrolytic), the same capacitance, rated for the same voltage (at least), and installed with the right polarity, it should do the job. In some circuits how precisely the cap matches its nominal value may -- but generally that problem doesn't arise in consumer circuits, and/or the circuit is designed so you can tune it to adjust for that variation. In some cases the exact charging/discharging characteristics and internal resistance and leakage current can matter, but again that's unlikely to be significant in a simple audio amplifier. Have fun...