KLH Thirty crossover cap help

[usamike10]

Got a pair of KLH 30's and want to replace the crossover caps. I need help identifing the black component on the board. It has two leads on one side and a single on the other. Without schematics I'm not sure what it is?

 

[SoundOfSound]

It's a double cap.

2uF + 2uF

 

[ra.ra]

Yep, replace it with two single 2uf caps with leads twisted/soldered together at one end.

 

[usamike10]

Is that double cap replacement easy to find? It also reads 50vnp, assuming that's rated for up to 50 volts?

 

[usamike10]

Would the 2 replacement caps be in parallel or series?

 

[SoundOfSound]

You could use two of these.

Tie one end together and hook up the other ends to where they go.

I not sure if they are actually parallel.

http://www.parts-express.com/solen-20uf-400v-polypropylene-capacitor--027-534

 

[ra.ra]

You'll be hard pressed to find a double cap like that, but something like these would be very suitable (2 per cabinet). Put 'em side-by-side as if they were going to be "in parallel", but you only connect the leads on one end, leaving the other ends to reach their individual contacts on the backside of the circuit board.

http://www.parts-express.com/dayton-audio-dmpc-20-20uf-250v-polypropylene-capacitor--027-414
http://www.parts-express.com/dayton-audio-pmpc-20-20uf-250v-precision-audio-capacitor--027-214

edit: oh yeah, you'll probably want to replace that little 8uf cap as well.
edit edit: no, you do not want them to actually be in parallel since that would result in a 4uf value which is not part of this speaker's crossover design.

 

[usamike10]

Bare with me guys, so I'm trying to understand, from a positive and negative aspect. The current cap has 3 leads, from the pic, + is on the left? From what I gather, I will be tying the two new caps together + to -, and connecting the other + and - to the board? If so, looks like + on the left and - on the right per the picture? Thanks in advance!

 

[ra.ra]

Looks like your cap says 50VNP (or 50 volts non-polar) which indicates that polarity is not an issue regarding cap placement, except that the original double cap is an oddball and can only be installed the way it has.

See sketch attached - hope this is helpful.

 

[usamike10]

A picture is worth a thousand words, I get it now, thanks!

 

[gbroot]

FYI, it's fine to go above the original 50V rating too. I think the Dayton Caps from parts Express are rated 250V. It never hurts to go higher than the original rating. So your parts list would look like this. 4 2uf 250V Non-polar and 2 8uf 250V Non polar (bipolar). Total cost should be around 15.00 + shipping.

Edit: sorry I didn't see the prior links to parts express

 

[ra.ra]

And this will be close enough to replace the original 8uf caps.

http://www.parts-express.com/dayton-audio-dmpc-82-82uf-250v-polypropylene-capacitor--027-426

 

[usamike10]

Are you saying its okay to replace the 8uf electrolytic with a non-polarized poly?

 

[ra.ra]

Yeah, sure, that's done every day with these speaker rehabs. The caps I listed in post 7 were also polys, one with 5% tolerance (very adequate) and one with 1% tolerance (overkill?). This needn't turn into yet another cap debate, but I think it would be fair to say that many, if not most, audio hobbyists typically replace the smaller value original NPE's with modern film caps (be they polypropylene or polyester or whatever) in the circuits for the tweeter and mid-range drivers.

If you've never done this before, just be mindful that the new poly caps are normally much larger than the original NPE's and that needs to be considered when tight space is a concern. Also, in general as voltage increases, so does the physical cap dimension. PE is really good at listing the cap size in their description, and even a 8uf poly cap will only be the size of your thumb.

If you want to stay with NPE caps, this one would also help freshen up your speakers very well, but after only a very short look-see, I did not spot an NPE cap rated at 2uf, and you might have to resort to other values to make up or get near to the original 2uf value you need.

http://www.parts-express.com/80uf-100v-electrolytic-non-polarized-crossover-capacitor--027-338

 

[able.baker]

a picture is indeed worth a thousand words

Nice pic - ra.ra!

 

[usamike10]

Thanks ra.ra, great information!