Thought I'd start a photo and information thread on vintage sound equipment, this was inspired by " A Zenith Nut"'s question earlier today on a different post about Webster-Chicago and Webster Electric and why they were separate companies "legally"...I realized some of the sound equip. history is now being forgotten..

I'll generally showcase P.A. & commercial tube amplifiers for this one, though a few related microphones, studio gear and speakers may appear as well...
Everyone is welcome to post photos and descriptions of their own favorite vintage sound pieces to share here...
Vintage Hi-Fi audio unless used sometimes in the past for PA sound/ recording purposes should be excluded.

I get kind of tired of just seeing radios, test equipment and ham gear showcased most of the time on ARF, I think some of the amplifier designs
are just as interesting, even if circuits are largely simpler (with the exception of a W.E. PAB-1, etc)
Most look a lot more attractive than some of the "collectible radios" I've seen!

I'll begin with manufacturer's A- going to Z, here's some Airline Apparatus, Altec Lansing, Bogen Sound Systems and a Clough-Brengle!...

Feel free to post comments and general questions of common interest, send a PM if looking for schematics or similar questions about specific units...

I'll try to add more models as I find the time (and the amps, where did I put that? )

-Kent

Descriptions:
Airline equipment shown includes a 3160V amplifier from the late '30's (made by E.P.I. or Hallicrafters) using 6F6G in P/P, a pair of Electro- Voice made V-1 (Hi-Z) ribbon mics made for Montgomery Ward, a plate off a old MW gas fridge I found out on the land, Airline headphones and a lower end early '40's radio console below (forget model offhand)...

Altec 342B- This is one of the last models made (Perhaps early 1970"s?), it's in great shape and has not been rebuilt yet...I used a pair of these for many years as my studio monitor amplifiers and sounded as nice as most Hi-Fi systems...When I received it I removed the modern emblem "342B" front cover and replaced with a early 342A cover for appearance sake. These use 7027A tubes in P/P for 35watts opt.

Altec 352A- The SS version of the 342 above...I first got into vintage sound back in 1999 on account of these amps...A friend of mine found a pair of these at auction at Wash. state Univ..When I went up to visit, he sold me the pair for $100...I since sold the "better" looking one of the 2...
The one shown here was "donated" back to me by a musician friend of mine...When I first looked at these inside their cases, I was so naive we thought the transistor mic preamp octal plug ins were tubes! At least they were octal

Altec 602C- Duoflex (2-way) speakers built into RCA cabinets for probably 1960's live stage monitors, I use them today along with a HH Scott 222C
for my mixing room/stereo speakers, lack of space to use larger speakers...they sound pretty decent once the crossovers are renewed.

Bogen LLO- 1945-1947? hard to find mic preamplifier I rebuilt some years ago. No EQ which makes it nice for vocal tracks or most anything....
I like to use channel two which has a early Thordarson Tru-fidelity input transformer installed. In fact it's my favorite preamp for recording.

Bogen LOH- early '50's 4 channel mic preamplifier. This is a model without the "meter" installed, so you have to listen for levels.
The "L" in Bogen nomenclature stands for low impedance, the "H" for high impedance on their preamplifier/mixers, so this has Bogen input transformers
on the 4 channels and a HI-Z output. I added a old Stancor input transformer in reverse for balanced output as well.

This is my mono system. A Raspberry Pi, Stromberg Carlson AP 428 and an Altec 615A speaker. The S-C is from 1957 or so. The Altec has the Altec N1600 D crossover in a ceiling cabinet. Just turned it up on its side for use in our house. It sounds great.

That looks like it sounds real nice, thanks for posting!
The S-C AP-428 is a good example of what I'd call a 1950's "hybrid" amplifier , a unit that could have been used in a small church P.A. system, or part of a finer mono hi- fi set up on a medium budget.
Believe there's N-1600E? crossovers in my 1957 Altec V.O.T.T. speakers I haven't posted up yet, I have the same components (803A, 802C, 811B horn)
mounted in two separate style wood cabinets...Can't recall if I replaced the caps inside the crossovers or not years ago, I'll drag one out and take a look
as it really opens up the speakers when you do that.




Here's some Dukane/Operadio out of St. Charles, IL., a friend of mine rebuilt the 1U325 into my live guitar rig, a different circuit with original DuKane OPT. He did the same with the commercial 1A775, turning it into my bass amplifier, adding a larger Schumacher OPT to use 6550's rather than the stock harder to find 8417 tubes, a eq section, increased regulation, jacks for modern inputs/outputs..I put the crazy cabinet together and found I needed the foam cushion to keep the amp from jumping[i][/i] off the cabinet on stage during a "low" note.

The 1A140 is a 15 watt 6V6 P/P amp in unrestored condition.

The 1A65 is a 3 channel (6J7) hi-Z microphone (or line) tube preamplifier.
It's completely rebuilt and works nice when recording with Hi-Z ribbon mics, when you don't want to load them down with a low impedance transformer.

Hannon A-1228 Compressor Limiter (6BC8, Triad Transformers) aka ESECO Limpander

McGohan M-30 (6AU6 inputs, 6L6GB in P/P) 30 watts OPT.

McGohan M1003 100 watt ( 6EU7's, 8417's)- This I rebuilt as a backup power amp for live sound a few years back...
Last spring with the fine help of fellow ARFER Justin McInvale, I added a line level input to run a early US made Ensoniq KT-88 (can't resist that model #!)
88 weighted key piano through it. It sounds real nice through a EVM 12" high quality guitar speaker.

Those are cool mics, they certainly are more affordable than RCA ribbons, and have humbucking transformers too. Mine has some kind of foam? that decayed into a yellow hard blob inside and I need to clean that out but it would entail removing the element inside. Mine is a prewar type.

Well, kinda wimpy, 14 watt Heathkit mono.

Thanks Wazz!
It would be a good idea to get that "yellow blob" stuff out of your V-1 soon.

EDIT: If you are careful removing the ribbon motor assembly -Watch the humbucker wires so they don't snap, while holding motor loosely in one hand or on a clean table, you should be able to remove the "stuff", might want to put some light adhesive masking tape over the felt screen
to keep it as much as possible out of the ribbon "tunnel" as you clean it.

I recall a EV 726 dynamic mic I repaired where the yellow glob stuff had melted onto to the diaphragm and other places
where it is difficult to remove, also powders up and causes other problems with fidelity...

I replace with soundproofing foam though I 'd reckon 75 years from now, someone may be cursing me about that stuff!

That's a nice Heathkit setup Paul, looks like it uses 6BQ5's?, so it must sound pretty decent.
Liked your Airline portable on your site, doesn't look like case is damaged which is common with those models, rare find.

Yes, it is a pair of 6BQ5, as for the sound have only tested it with a signal generator and scope showed good bandwidth from 50 to 20 khz with a dummy load.
The Airline portable caught my eye because in 1950 a TV shop owner showed me one and I was blown away. A radio I could carry on my bike ! It was unbelievable for me in 1950. Of course it was way out of my paper route paygrade.