Crossover electronics upfit

Newbie question: with a pending PP capacitor upfit on my 4 ohm Mission 780 speakers, I find different voltage values available. Powered by 120w/ch RMS Yamaha receiver, (unfortunately!) not going to hack off townhouse neighbors with really high volume so are 600v caps necessary? I'm tending toward 5% tolerance also, thinking tighter tols mean more accurate response. Not looking to invest for 'the best of the best' - just want a money efficient solution updating quarter century old crossover caps in my old school legendary speakers. Open to general suggestions for all this plus specific component and parts source input.

Thanks! :cubehead:
 
Newbie question: with a pending PP capacitor upfit on my 4 ohm Mission 780 speakers, I find different voltage values available. Powered by 120w/ch RMS Yamaha receiver, (unfortunately!) not going to hack off townhouse neighbors with really high volume so are 600v caps necessary? I'm tending toward 5% tolerance also, thinking tighter tols mean more accurate response. Not looking to invest for 'the best of the best' - just want a money efficient solution updating quarter century old crossover caps in my old school legendary speakers. Open to general suggestions for all this plus specific component and parts source input.

Thanks! :cubehead:

600v caps are way overkill. 50 volts would be safe.
 
Polypropylene capacitors come in 250V, 400V and 650V and even 1000V ratings. These are often also used in high voltage mains applications.

A loudspeaker is unlikely to seriously need more than 50-100V at maximum which accords with the power supply rails in the amplifier. The received wisdom is that higher voltage types SOUND better. They can also be inconveniently HUGE to fit. :D

It is straightforward to upgrade NP electrolytics in tweeter filters to polys. Bass filters need more careful thought, since the approx 0.5 ohm resistance of a NP type has a significant effect on phase and (particularly) damping of the bass unit at crossover. This is generally accounted for in the design. It may be that you do best to replace, say, a 20uF NP type in a bass circuit with a 20uF poly and 10W 0.5 ohm wirewound resistor in series.