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Using WECo 107-Type Speakers as a Stereo System

Started by segaloco, November 20, 2023, 06:51:21 PM

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segaloco

Hello folks, I just successfully tested a little monstrosity I wired together on my desk, and was wondering, has anyone specced out and designed a stereo sound system based exclusively on 107-type speakers (or any WECo desk speakers really) and a talk voltage power supply?

In this case, I've got a WECo 20B2 with the 24V talk voltage and ground connected to pair 2 (Y-BK) of two faceplates, then sheath-ring running to pair 1 (R-G) of one plate and tip-ring going to pair 1 of the other plate.

One speaker is then plugged into each plate, delivering stereo sound.  I don't anticipate I'll actually use the 20B2 for the power for these, feels like overkill (and the thing buzzes...) but it was kinda cool actually hearing this come to life, just clobbered together from telecom equipment.  My more formal plan is to build a little interface with a two port plate for plugging in the two speakers, a 1/4" stereo jack (TRS), and probably a built in rectifier so I can just run mains into it.

Has anyone else done this specific thing, rigging up a set of 107-type (or really again any WECo desk speakers) as conventional audio speakers?  Is that something folks suspect they'd have a long term tolerance for?  Music and such tends to be more consistent signal hitting the speaker over longer periods of time than, say, a phone call, but hold music and such have been a thing for a long time, so I would expect continuous audio signal to the speakers to be within their tolerances, even if it's more than just voices.  Unfortunately I don't have a paper BSP on these and I wanted to see if I could pull it off without doing any internet searching, and was successful.  In any case, I'll go familiarize myself with BSPs as well.

In any case, this is exciting, as I've never technically purchased speakers for my computer ever, the pairs I've used over the years have always been things I've inherited moving out of somewhere or found in a free pile.

Attached a few pictures so people can make fun of my rats-nest-approach to gator clips :P

Lastly, this is my first time actually seeing a 107-type speaker outside of pictures, and the pictures I've seen have all been just the speaker with no point of reference, I didn't realize they were so small!  I had it in my head that they were the same size as the 108-type speaker, I'm actually quite pleased though, I was anticipating needing more desk space for them, these instead will fit nicely where my current speakers are.

Edited to add "WECo" to the subject, qualifying 107-Type Speakers.

SUnset2

It looks like you should be able to get some low-fi music.
When I was a kid (about 1970) I got a GE stereo record player at a thrift store that was missing its detachable speakers.  I found a couple of Teletalk (Webster) intercom speakers (4 or 5 inch) and hooked them up.  Voila! stereo.  No bass, no treble, but it was stereo.  For my next upgrade, I took two 52A operator's headsets that were missing the boom microphones, hooked them up to the speaker outputs, and put them both on my head, one on each side.  Wow! stereo headphones, with all the hi-fi that a 302 could deliver!

AL_as_needed

Having a 107 type speaker, this not only makes me smile, but also gives me some "bad" ideas  8) . If WE made a stereo, it would probably look similar. I know WE did make larger speaker /PA system type stuff. Was that something they continued or was a small off-shoot of the phone business?
TWinbrook7

G-Man

As has already been pointed out, their poor frequency response and lack of ability to handle even a moderate power level would leave the listener with a less than enjoyable experience.
 
Remember, Bell Labs/Western Electric purposely designed much of their PSTN equipment to have a +/- 200-3,000Kc of bandpass. This allowed carrier and other transmission equipment to handle many more channels of telephone/telegraph and data traffic.
 
 However, that would not preclude their usefulness to listen remotely to a talk program on an AM radio station or to be used as extension speakers for a radio scanner and other similar lo-fi applications.

SUnset2

Quote from: AL_as_needed on November 20, 2023, 08:58:31 PM... If WE made a stereo, it would probably look similar. I know WE did make larger speaker /PA system type stuff. Was that something they continued or was a small off-shoot of the phone business?
I assume that you are aware that in their day, Western Electric made what was considered the best professional sound systems.  They invented the first successful motion picture sound system (Vitaphone sound-on-disc) in the 1920s and provided the complete system, including microphones, recorders, reproducers, amplifiers and loudspeakers.  They continued with optical sound-on-film from 1930, and with magnetic stereophonic sound in the 1950s.  The antitrust folks came after them, and in the early 1950s, they spun off the microphones and reproduction equipment as Altec, and the recording equipment as Westrex.  Their old equipment is highly sought after.

If you look at the last of the credits on old movies, they will have a logo for either Western Electric sound recording or for RCA sound recording.

G-Man

#5
Quote from: AL_as_needed on November 20, 2023, 08:58:31 PMHaving a 107 type speaker, this not only makes me smile, but also gives me some "bad" ideas  8) . If WE made a stereo, it would probably look similar. I know WE did make larger speaker /PA system type stuff. Was that something they continued or was a small off-shoot of the phone business?
Yes, Western Electric ushered in the electronics age starting with the development of the first successful electron tube, a.k.a., vacuum tube or in British parlance, valve. It was first employed for use on the Transcontinental Telephone Line circa 1914/1915.
 
WECo also produced the first public address and carrier systems.
 
WECo and AT&T opened one of the very first radio stations, provided radiotelephone equipment for the U.S. Military. They also provided the high quality program circuits for NBC, CBS, ABC, Mutual and other radio networks of the day.
 
And as Sunset 2 stated, developed motion picture sound, first using large, wax transcription disc, and then using an optical sound track. Warner Brothers produced the first successful sound motion picture when they released The Jazz Singer in 1927, using Bell Labs designs and WECo's equipment, calling it the Vitaphone system.

https://www.youtube.com/watch?v=KD_YRnuuKyY

It was so successful, Bell Labs/WECo created an entirely new division named. Electrical Research Products Inc. In 1936, the Feds started hollering about antitrust implications, and it was sold to a group of ERPI/WECo engineers and executives and renamed ALTEC.
 
Stereo??
 
Well check out the following from the Library of Congress:
 

 
 
 
 
 

AL_as_needed

Gman & SUnset2; very interesting information! I was aware that they had a very serious hand in sound equipment in the 20s and 30s, but not to that extent. A shame the anti-trust laws of the took some of the wind out of their sails. If allowed to continue with their work, one can only guess where that would have taken us.
TWinbrook7

segaloco

Cool to know the Altec connection, I've never followed their theater sound business down the same way as I've followed their computing business, so many heads to the hydra that persist to this day...and I have a hard enough time explaining to friends around here Lumen's lineage.  I wonder if any of these various Bell System descendants have considered some sort of family reunion-type promotional thing.  It'd be cool to see a trade show or something like that put together consisting exclusively of the modern-day descendants of various parts of the Bell System....a sort of where are they now and what are they up to.

5415551212

Stereo? Amazing idea not sure how I would do that? Line 2?
Well since I am old and booooring,
I use a old 'music on hold' adapter along with my DP-1900 to pump analog sound (BBC world service or NPR news) into my phone system throughout the house on one of my intercom lines.

Its great fun when guests pick up my old phones and here the good o'l BBC.
Of course its not intrusive unless you take a phone off the hook and turn a 107 on.

For loads of fun you can actually do 'phone karaoke' (which I claim to have invented)  with a music on hold adapter intercom line, phone and 107 or other WE speaker.

 

segaloco

Just a followup now that I've actually built a little interface.  It's about as spartan as they come, and I'm not one for appearances, I'm an engineer dangit!  This was fun to throw together, just two generic two-pair wall plates, parallel wiring on both the audio and power circuits.  Lucked out in that the barrel jack I picked up actually fits another existing transformer I had no use for, and it seems to power these just fine.

The 1/4" jack was fun...I had an old ABY box an old bandmate gave me that he alleged at the time was broken, and I wound up keeping it around just for this sort of thing.  I took the board out of it, scored between the three inputs, and snapped them apart.  To achieve a solder-free build (aside from what was already there) I just wire-wrapped the tip, ring, and sheath contacts and ran them into the circuit that way.  Once I verified it was all working, found a piece of scrap wood to hold the audio jack down since I trimmed the PCB a little too close and then couldn't put screws in it.

I'm quite pleased with this as I have a musical performance in February that I'm trying to base on as much telecom equipment as possible, so this'll allow me to use these speakers as my mains.  They are quite band limited as described up thread, but this is a noise performance so I don't really care about fidelity, the more unpredictable gremlins in my audio chain, the better!