N501-8A Question

[dgwojo]

Steve,
Cap values can be added together when wired in parallel, an 18 and 10 can be added together to get the 28 if that's the proper value for the 501-8A crossover. Some claim that it's actually better to have two or three caps added together for the correct value and best sound. Also, don't forget the "bypass" caps!! I don't know anything about the coils, but here's a link with a good crossover calculator, use the 12db x-over; http://www.selectproducts.com/calculators.html
Good luck, Dave.

[Steve Ty]

Thanks Dave -- I should have known that -- been too long since I took physics.

While we?re on the subject of N501-8A?s -- I notice that Altec used very small wire in these things -- looks like 20 or 22 gauge. Would it be beneficial to beef-up the wire while I?m in there? I have no idea what the electronic properties of the L-Pads are -- I assume they can handle the load and are OK.

BTW, I bi-amped these speakers, and they sounded great -- when I switched to the N501-8A?s -- things went down hill.

Thanks, Steve

[Steve Ty]

I need to replace the caps & chokes in a couple old Altec N501-8A's (I'm assuming the L-pads are OK).

I think the values are 28mfd & 3.6mh.

My usual sources (Part Express & MCM), don't have them. Anybody know where I can find these things? Also, I notice there are several different types of capacitors -- which is best for this application?

I'm using them between a pair of JBL 2226J's and an Altec 511B w/902.

Thanks

[dennis gilliam]

I've seen several of these with the coils open.

A little too much "thump" perhaps using new power amps and deep bass music choices, but nonetheless they could use a little more current capacity in the choke. Several sources are on the web for toriodal chokes that replace the originals just fine.

I've notices the caps are always OK, but I change them out to oil type motor caps as a matter of upgrade. Shop about for these, they are really cheap from motor or HVAC surplus sites.

Replacement values to within a Hy or mF are good enough.

BTW, Biamping always improves things when a good ECO is used.

DG

[joejoe723]

Hi conelrad,

I used motor caps before but i found that motor caps often have a leakage current.

[dgwojo]

Steve, yes the N501-8A uses some pretty thin wire, it's probably about 18 guage, I asked an Altec dealer about that back in 1977, he said it's sufficient for short wire runs. I agree the L-pads are fine, I've seen many fried caps, usualy the horn diaphragms are toasted when the caps go bad. I like to upgrade these with Solen FastCaps, add Bennic bypass caps, and Zobel networks for stable woofer impedance, best of luck, Dave.