Ohm Model E crossover question(s)

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ohmegoodness

New Member
These were my first speakers ever, purchased in 1974. I have replaced the woofer in one of them and refoamed. Recently the other original woofer started sounding a little funny. If I gently manipulate the cone, I don't feel any sort of scraping, so I wondered if maybe I should re-cap before I do anything else. What could it hurt? Anyway it should be good practice as I am a complete newbie when it comes to this stuff and I have a pr. of KLH model 5's I need to do eventually.

I am posting a couple pics. It looks like a super simple setup with just a few bits wired together between the woofer and tweeter terminals. Trouble is, having never done these sorts of repairs, I am not sure exactly what I am looking at, or where to buy replacements. Can someone help me out? TIA

IMG_1160_zpsa9bnvr0t.jpg

IMG_1161_zpszabyeq8s.jpg
 
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I'm not familiar with the crossover on those, but the parts in the first picture only affect the tweeter. Can't tell what goes where in the 2nd picture. Capacitors pass hi frequencies and block low ones. Unless there is a cap in parallel with the woofer, the caps only affect the tweeter.
 
The leads from where the speaker cables attach go to the two woofer terminals. One of them is then branched to one tweeter terminal. The second woofer terminal sends a branch to the second tweeter terminal, and this branch is what I have shown. All three components (2 caps and a resistor?) are between the woofer and the tweeter on that line, so as you said, only appear to affect the tweeter.

I went on Parts Express and found these:
http://www.parts-express.com/4-ohm-5w-resistor-wire-wound-5-tolerance--015-4
Is that a reasonable replacement for the tan bit?

http://www.parts-express.com/dayton-audio-pmpc-82-82uf-250v-precision-audio-capacitor--027-242
Would that work for the black cap?

I did not see any capacitors with a 25V rating, so I'm not sure what to do about the white cap. Actually, as is probably quite obvious, I'm not sure what to do about any of it!
 
The resistor is likely just fine and does not need replacing, but that one would work.
That cap is fine too, you've selected 1% tolerance which is the 'nicer' quality.
Voltage rating only matters in the sense that you don't want to go BELOW the original. Higher is fine.
It's odd that there is a cap followed by a cap/resistor in series with the tweeter. Anyway you should probably also replace that 2 uf cap that's with the resistor.

[Edit: I could see the 2 uf cap/resistor as a shunt across the tweeter to cut down the high end. The 8.2 might make sense for an initial splitting of mid/high frequencies, followed by contouring with the cap/resistor shunt.]
 
BTW I typically use the 'audio grade non-inductive resistors', may cost a few more cents but it avoids introducing inductance where there shouldn't be any. Wattage should be at least as high as the original. Higher is better, it just gives more mass and surface area for it to dissipate heat.
 
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