FS: Pair of RCA BA-31A Germanium Preamplifiers

sandpanda · Post by **sandpanda** » Wed Nov 29, 2006 1:54 pm

Same circuit as the BA-71... These are the earlier version with 4 germanium transistors. I have two more that I am keeping for sure, but I would love for these two to go to a good home. You'll need to put your own pigtails on these; they do have built in power supplies, however, so the rack job is easy as pie. I'd love to get 600 for the pair but I would consider letting them go individually so make an offer.

getreel · Post by **getreel** » Thu Nov 30, 2006 4:49 pm

pics?

sandpanda · Post by **sandpanda** » Thu Nov 30, 2006 6:40 pm

They are in great condition, I can take pics tomorrow to post.

sandpanda · Post by **sandpanda** » Fri Dec 01, 2006 11:39 am

Unfortunately my actual camera isn't working, but I just took these with my phone:

drumsound · Post by **drumsound** » Fri Dec 01, 2006 2:35 pm

So besides the pigtails are these thing ready to use? How do they get power?

sandpanda · Post by **sandpanda** » Fri Dec 01, 2006 2:52 pm

Yes totally ready to use... they have built-in power supplies, meaning you just hook them up to 110VAC and you're good to go.

drumsound · Post by **drumsound** » Fri Dec 01, 2006 3:31 pm

Ya interested in a Brick?

syrupcore · Post by **syrupcore** » Sat Dec 02, 2006 5:29 pm

what are pigtails?

sandpanda · Post by **sandpanda** » Sat Dec 02, 2006 6:57 pm

It's basically half an xlr cable so you can hook the mic right up to it.

emrr · Post by **emrr** » Sat Dec 02, 2006 9:48 pm

Sorry to spoil your description, but those are BA-31A's with the factory upgrade cicuit boards, which have only one germanium transistor. Which makes them BA-31B's or BA-31C's in BA-31A clothing. A real 'A' variant has six transistors, all of which are germanium. They are fucking rare as hell, because they were almost all upgraded in 1961 when RCA pushed the replacement boards on everyone who'd bought the 'inferior' six transistor version. Look up the transistor #'s if you are in doubt. The schematic online at waltzingbear.com is incorrectly labeled; it is actually the BA-31C.

sandpanda · Post by **sandpanda** » Mon Dec 04, 2006 9:11 pm

You are correct, sir. However, not knowing that the A's were far rarer and more desireable, I'm not asking more than I've seen B's going for. If anyone cares to make an offer, I'm certainly amenable to that.

emrr · Post by **emrr** » Mon Dec 04, 2006 10:08 pm

Sorry, neglected to say your price seems correct. And these are real cool sounding units.

spacelabstudio · Post by **spacelabstudio** » Wed Dec 06, 2006 8:54 am

How do you set gain?

??????? · Post by **???????** » Wed Dec 06, 2006 11:14 am

was wondering that myself!!!

drumsound · Post by **drumsound** » Wed Dec 06, 2006 11:24 am

Probably set gain like an old Tele V72. The 'trick' is to put a comp or a console fader after the pre to control the level to tape.

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FS: Pair of RCA BA-31A Germanium Preamplifiers

FS: Pair of RCA BA-31A Germanium Preamplifiers

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