Replacement capacitors exploding

oh and to someones point a DC offset might have an impact on a NP cap (if its big enough) but not on a film.
Which brings up an interesting theory on how it failed originally - if in fact you have enough DC (easy to measure) a BP cap, which is designed for AC on a small, ideally zero, DC base (need the spec sheet for more) could have failed.  And the replacement.
Putting in a film would stop that failure but not the DC offset - which is likely  applied to your woofer BTW.

Examples of electrolytics, specifically for crossovers: (https://theaudiocrafts.com/x-over-parts/audio-grade-capacitors/bennic-non-polar-electrolytic-capacit...)   and:  (https://theaudiocrafts.com/x-over-parts/audio-grade-capacitors/panasonic-bipolar-andquot-for-audio-c...)          For a large selection of quality crossover capacitors, these guys are a go-to:  (https://www.madisoundspeakerstore.com/capacitors/)

rodman99999 - Thanks for the link to Madisound, good info to have around. itsjustme - Not so good...

For best performance and long term reliability, crossover caps MUST be NON polar FILM capacitors PERIOD.

You should NEVER use electrolytic capacitors for that purpose (well, they may be kludged back to back but forget it). Furthermore, you should pick ones with the highest voltage rating that you can find, since they are subject to AC voltages in the crossover. You can NEVER go wrong with higher voltage ratings. Buy the HIGHEST voltage rated version that you can find. They will be more expensive, but you will sleep better.

If you have accidentally used electrolytics, they will blow almost immediately.

Here are some excellent examples:

https://www.partsconnexion.com/Jantzen-film-caps.html

The silver ones are rated up to 1200 VDC, which is probably ok for about  up to 300VAC, which is more than any power amplifier can ever put out and they will outlast your house.

If you go with a high voltage higher quality cap of the same value you will have no problems but they will be expensive try a solen cap of the same value they are not too expensive and they will outperform the originals.