help buying capacitors

I don't think you want Black Gate for speakers, and if you do good luck finding the high value not polar types.

I suggest that there are other good caps: Mundorf, Hovland, Auri, Sonic Cap, etc. The can be found on the net.

For larger values, parallel them, for not in circuit types , eq's for drivers etc. use Solen or Madisound's or Parts Express lower cost Polypro types. For tweets the foil variety is usually better sounding but be prepared for sticker shock!

loon

Try here:
http://www.partsconnexion.com/catalog/CapacitorsElectrolytic.html

A great vendor to work with.

If you have to have Black Gates, Michael Percy sells them and has explanations of the types. But Loon is correct--I'd never put a 'lytic into a speaker, and SCRs (Axon, Solen, etc.) 'propylenes are great, bypassed with something better, for the high-value locations and are highly affordable. Percy also sells LOTS of other high-quality film caps. http://www.percyaudio.com/Catalog.pdf

For higher-quality caps for use in series with the signal, I prefer North Creek's Zen, Harmony, and Crescendo 'propylenes, with the Harmony metalized also highly affordable. http://www.northcreekmusic.com/CrossoverComponents.html
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