FS: Vintage Military Tube Compressor 1957: Federal AM864/U

tubemonkey35 · Post by **tubemonkey35** » Wed Jan 04, 2012 6:36 pm

Hi, I'm doing something I said I'd never do, I'm selling one of my vintage military tube compressors. This particular Federal AM864/u from my collection is quite special sounding. It's fully functional, comes with Mogami wired pigtails (by me), recapped, and original tubes.This same unit saw duty at Henry Hirsch's Waterfront Studio while I was assisting him. I'm asking $1,750 plus shipping and insurance. Cosmetically it's great, though one of the rack ears is bent slightly and the little has a little rash. It's PLUG & PLAY!

See the pictures here: http://www.flickr.com/photos/62721651@N ... 724650735/

-Adam

tubemonkey35 · Post by **tubemonkey35** » Fri Jan 06, 2012 7:31 am

tubemonkey35 · Post by **tubemonkey35** » Thu Jan 12, 2012 11:24 am

junomat · Post by **junomat** » Sat Jan 21, 2012 7:49 am

What's that resistor you have on the output?

tubemonkey35 · Post by **tubemonkey35** » Sat Jan 21, 2012 9:17 am

It's just a 620 ohm resistor to pad down the output; the output tends to be quite hot on these military tube comps.

junomat · Post by **junomat** » Sat Jan 21, 2012 9:20 am

tubemonkey35 wrote:It's just a 620 ohm resistor to pad down the output; the output tends to be quite hot on these military tube comps.

Sweet... Just added it... Works like a charm.

Just curious also, I have mine wired the same way - so since it's not wired through the center tap, does that mean the signal isn't going through the trannies?

M.

tubemonkey35 · Post by **tubemonkey35** » Sat Jan 21, 2012 10:47 am

You are still going through the Transformer. The way you see it connected in the pics was for my previous setup; This is the unbalanced way to connect it.

Per the manual when connecting for balanced you connect the Center Tap to the grounding post.

junomat · Post by **junomat** » Sun Jan 22, 2012 9:17 am

Gotcha.

So having a jumper between the neutral and the ground is unbalanced?

Sorry for all the questions...

tubemonkey35 · Post by **tubemonkey35** » Sun Jan 22, 2012 10:14 am

Yes, that's what is stated in the manual. Without use of CT, jumper ground and neg post = unbal. CT jumper-ed to ground is balanced, with the other two posts being your + and -.

tubemonkey35 · Post by **tubemonkey35** » Sun Jan 29, 2012 11:39 am

tubemonkey35 · Post by **tubemonkey35** » Fri Feb 03, 2012 7:51 am

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FS: Vintage Military Tube Compressor 1957: Federal AM864/U

FS: Vintage Military Tube Compressor 1957: Federal AM864/U

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