Bob Hedberg wrote in
:

non-pcb caps show up on ebay a lot. I've gotten a few there.
There's quite a selection of pp foil and pp metalized foil caps
available on the tube parts sites, also. Many of these are 250 v
versions for speaker crossovers.


250 Volts! WOW! That comes to over 7800 watts at 8 ohms!

r



http://www.madisound.com/

http://www.partsexpress.com/webpage....&WebPage_ID=69

Angela and Handmade has large value Solens, also.

Bob Hedberg

rod keys wrote:

Gents,

The last time I built speaker cross-overs was MANY moons ago. I used
"oil filled" caps about 20 mfd that were meant for timing circuits in
old vacuum tube instruments. (I know, 20 mfd = rather low crossover
frequency). But I'm not able to find such caps any more!

The problem is three fold. 1) Rather high mfd value, 2) Need to be
non-polarized, 3) Need to sound "clean" (no extra internal
resustance, inductance or "chunkie" electrolytic action). The old
trick of electrolytics wired "back to back" works - kinda - but they
sound like electrolytics ... (read, how to make a perfectly good tube
amp sound like a solid state amp).

What's available for good cross-over caps today? Are motor starter caps
true oil fills or some cock-eyed variation on electrolytics?

And what's with PCB content in old oil caps? I must admit that I find
PCB paranoia more hype than science, but it seems like it's driven many
good components out of the market. Is this why real oil fills have
disappeared?

Rod

Bob H.

Just grab that plate in one hand, the chassis in the other,
and FEEL the power of tube audio!!!
(not literally, of course, just kidding. DON'T DO THAT!)





--
"Any sufficiently advanced technology is indistinguishable from
magic."

Arthur C. Clarke (1917 - ), "Technology and the Future"