Author Topic: BA Custom Adapter?  (Read 610 times)

Offline DazedConfused2

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BA Custom Adapter?
« on: January 24, 2017, 07:27:40 AM »
Hi all. First post. Will see if I can do this properly.

Anyone ever seen one of these? "BA Custom Adapter". Can find nothing on it.

Preamp of some sort. Picked up a while back at estate sale, and somebody had an entire stereo system rigged up crazy, which also had a Shure M65 preamp, and some other stuff cobbled together.

Hopefully, the attached pics display? If not, will figure out later. Have to get to work.

If anyone knows anything about these, any info would be appreciated.

Thank you,

Dazed




Offline DazedConfused2

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Re: BA Custom Adapter?
« Reply #1 on: January 24, 2017, 07:29:11 AM »
Don't know why they appear upside down?!

Thanks,

Dazed

Offline ataudio

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Re: BA Custom Adapter?
« Reply #2 on: January 25, 2017, 08:02:09 PM »
I got nothing.  Looks like a well made unit....What ever it is.

Offline OldiesButGoodies

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Re: BA Custom Adapter?
« Reply #3 on: January 25, 2017, 08:54:31 PM »
looks to be a preamp of some sort.  have you tried injecting a signal into the 1st set of rca jacks and listening to the other two while tweaking the pots in front?   I use one of these adapters w cheap radio shack cans just to hear what is going on with the signal before connecting anything expensive: 

http://www.zzounds.com/item--HOSYPR257?siid=134302

If the pair on the left is not the input then try the far right.  The unit looks to be old but is amazingly clean!


Spkr: Harbeth 30.1 on Sound Anchor 4 post stands
Pre: Rogue 99 Magnum
Phono: VPI Aries 1,  Van de Hul Frog
CD: Oppo 203
Cass: Tascam 122MkII
R2R: Revox B77
Sub:

Offline MacGeek

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Re: BA Custom Adapter?
« Reply #4 on: January 25, 2017, 09:42:22 PM »
You might want to try it on  variac first
MAC C-46 pre, MQ 108 eq, MC 352 amps (2), MR 78 tuner, MCD 500 CD, MPI-4 scope, LS 352 speakers, Sony HDR-F1HD AM/FM/HD tuner, Denon DRS 810 cassette, Denon CDR-W1500 CD recorder, Music Hall MMF-9 w/B&O MMC2, Revox A-77 R to R.

Offline OldiesButGoodies

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Re: BA Custom Adapter?
« Reply #5 on: January 25, 2017, 09:50:06 PM »
You might want to try it on  variac first

Absolutely, agree.  If you have access to a variac do that.  If not,  plug it in and run in the opposite direction, come back in no explosions or smoke follows.

Spkr: Harbeth 30.1 on Sound Anchor 4 post stands
Pre: Rogue 99 Magnum
Phono: VPI Aries 1,  Van de Hul Frog
CD: Oppo 203
Cass: Tascam 122MkII
R2R: Revox B77
Sub:

Offline DazedConfused2

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Re: BA Custom Adapter?
« Reply #6 on: January 26, 2017, 07:29:59 AM »
Thanks, all.

Actually, not sure about just turning it on, yet. That tall tube is a 6AQ5A, along with two 12AT7 tubes, and a 7025 (12AX7).

Can't get my head around a "stereo" gadget with what may be one low-power output tube, and not sure about firing it up without a load. Not sure what to connect load to, soooo....

Also not sure what that black/yellow wire coming out the back does. Looks like it could be a speaker connector, or it could be a remote power line.

Guess I'm just going to have to start drawing the thing out, and see if anything makes sense. That's why I was hoping to find a schematic. And, the name on it...BA Custom "Adapter"...? Adapting, what?!

BTW, I do have a Variac, signal generator, o'scope and all that. Just an intriguing oddball, here. And, it IS well-built, and using quality components. Got an old Merrill SA30 intefrated amp in the deal, with a bunch of switching boxes, and other stuff. I have no idea what that guy cobbled up, and a lot was not connected, all in a large homemade wooden enclosure. I just paid my $30, came home and kept the interesting, and got rid of the junk.

If I find anything, will post back.

Thanks,

Dazed

Offline Sir Thrift-a-Lot

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Re: BA Custom Adapter?
« Reply #7 on: January 26, 2017, 12:49:49 PM »

Can't get my head around a "stereo" gadget with what may be one low-power output tube, and not sure about firing it up without a load. Not sure what to connect load to, soooo....

Also not sure what that black/yellow wire coming out the back does. Looks like it could be a speaker connector, or it could be a remote power line.

 And, the name on it...BA Custom "Adapter"...? Adapting, what?!



I am NOT an expert by any definition, so take my opinions for what they are worth.   I don't see anything that looks like an OPT or an output transistor.   I assumed at first glance that they were using the word "adapter" as a synonym for preamp.   I don't see anything that looks like it would drive a speaker, so there is no "load" to worry about.   My guess on the black/yellow is that it looks like a bulb socket.   This was probably in some sort of cabinet and that was the power on indicator at a remote spot on the face of the cabinet.   My guess is that the three RCAs are inputs for "channel A" and "channel B", and the third set is outputs to a power amp (trace back from those pots to figure out which is which).   

Perhaps this was early in the stereo era and the word "adapter" is used for this being integrated into a mono system.

Offline MacGeek

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Re: BA Custom Adapter?
« Reply #8 on: January 26, 2017, 05:09:13 PM »
A few thoughts.....In the early days of stereo, definitely during the tube era, there were a number of "adaptors".  Multiplex adaptors to convert mono tuners to stereo, which this does not appear to be and stereo adaptors to allow mono preamps to function in stereo.  It might also be a head amp to allow what would then have been reel to reel tape deck heads to be connected to a high level amp/pre-amp inputs.  Early Mac preamps and others, had a tape head input, in addition to phono and high level.  It might also be a phono pre, since many very early phono inputs were designed for ceramic, high level, inputs.
MAC C-46 pre, MQ 108 eq, MC 352 amps (2), MR 78 tuner, MCD 500 CD, MPI-4 scope, LS 352 speakers, Sony HDR-F1HD AM/FM/HD tuner, Denon DRS 810 cassette, Denon CDR-W1500 CD recorder, Music Hall MMF-9 w/B&O MMC2, Revox A-77 R to R.