Cap Dilema

[Phantom499]

I plan refurbishing some 30yr old speakers. Unfortunately the Xover boards have insufficient room to fit polypropylene caps, so is it worth replacing the existing caps with like for like electrolytics or is this a waste of time?

This is my first attempt at DIY audio so anything complicated like making new boards ect would be beyond my ability

[sdclc126]

It will be a relatively cheap refurbish to replace the caps. Electrolytics can degrade over time and thus their values can change. Whether or not this results in an audible improvement to the speakers remains to be heard.

[elac310]

Your boards look like PCBs. If you really want to do something nice (and the speaker is worth it), you could remove those PCBs and hard wire everything (using electric cable for interconnecting components) on a wood-planck that meets your needs, size-wise, to accommodate non-lytic caps, and possibly bigger (air)coils as those tiny coils tend to get rapidly into saturation.

If you have no reasons to believe your capacitors have dried out right now, an alternative could be to solder on each lytic cap a film cap of 0.1uF but space is scarce, indeed.

[speakerdoctor]

Replace with audio grade quality (i.e. Bennic) caps and be done with it. They will fit and last at least 15-20 years and sound just fine.

DO IT!

[Phantom499]

Originally Posted by speakerdoctor

Replace with audio grade quality (i.e. Bennic) caps and be done with it. They will fit and last at least 15-20 years and sound just fine.

DO IT!

The problem is though that polypropylene film caps are too large to fit on the board, hence the qestion as to whether it was worth replacing with modern electroytic caps?

[UV101]

I would not ever recommend fitting elco's in the signal path!!!

You could easily improvise with some basic poly caps and get them in there. Mine were much bigger then the original caps so I stacked them and used hot glue ;-)

[Brett]

Originally Posted by Phantom499

The problem is though that polypropylene film caps are too large to fit on the board, hence the qestion as to whether it was worth replacing with modern electroytic caps?

Why bother with the original PCBs? Just point to point them using some tagstrips.

[Bamalama]

That's what I do. The last two commercial pairs of speakers I bought, now have wires going out the back and old-style tube-circuit tag strips with all the capacitors and resistors on them, mounted on the outside of the cabinet.

You could say it's hacky-looking, and it is. But if you do it nice and neat it's more like a hoodless Deuce showing the engine.

Let me add to the chorus, too, saying that taking the electrolytics out of the tweeter circuit and replacing them with film caps is just about the best thing you can do to your hi-fi. I won't get into what kind of film because I mix and match according to what I want to accomplish.

B

[AEIOU]

I personally stay away from using electrolytic capacitors in passive crossover networks. Some people say they cannot hear any difference, but I contend that I can hear a difference. If you do decide to use electrolytics, make sure you use NP Non Polarized. There are higher quality electrolytics available, but they tend to cost more too. You can mount, solder components to the wrong side of the circuit board to gain more room, the crossover/circuit will not know the difference. One way to fit more components into a small space is to stand them up as opposed to laying them down on the circuit board.

Originally Posted by Phantom499

The problem is though that polypropylene film caps are too large to fit on the board, hence the qestion as to whether it was worth replacing with modern electrolytic caps?

[Face]

You can't piggyback caps on top of each other or stand them on their sides? If you're on a tight budget, check out Dayton/Bennic caps.

To replace film caps with electrolytic caps seems *** backwards.