Categories
Technical

Audio Mixing Console Circa 1949

Download a three-page article from RADIO ELECTRONICS, Feb 1949, on the subject of Build Your Own Audio Control Console.  Author is Richard Dorf.

DOWNLOAD: AudioConsole1949

Kinda a wacky design: it’s intended for mixing four low-z unbalanced sources, using multiple T-pads summing through a resistor network to a single tube grid (rather than using multiple input transformers and multiple tubes).  Not really so practical. I’m posting this primarily in the hope that one of my readers can elucidate the output stage design for me.  It seems like it must be an error, but maybe not?

The article states that ‘any plate to line output transformer can be used,’ which means that the design does not specify an air-gapped (DC-handling) transformer.  Not sure how that applies to this design.  Seems like the DC would be quite different on either side of that 33k resistor?  Also not sure how any signal would develop there? Is it possible because on of the secondary legs is terminated to ground?  Confused.  Were there any commercially-manufactured pro-audio units that used this kind of line output stage?

Categories
Synthesizers Technical

1951: The Thyratone, a DIY Vacuum-Tube Monophonic Keyboard Synth

Download a ten-page pair of articles from RADIO ELECTRONICS, 1951, on the subject of building your own keyboard synth.  Author Richard H. Dorf.

DOWNLOAD: ThyratoneSynth1951

This has got to be one of the most insane DIY projects I have encountered from the era.   You would have to be a really ambitious MF’r to try and crack this one.  Also, and perhaps this goes without saying, it was very ahead of its time.   The Thyratone predates the appearance of the Musitron (AFAIK, the first synth to be used on a pop hit) by eight years. Many now-accepted synthesizer features, such as variable attack and decay, are fixed in the this circuit so as to more closely create the sound of a conventional organ, but since everything in the article is more or less explained, it seems certainly possible to make these aspects player-adjustable.

Anyone ever tried building a keyboard-playable, all-tube synthesizer?  Success?

 

Categories
History Technical

Prepare For A Journey Thru Time And Space (*special soldering-iron edition)

How are y’all doin.  Sorry I’ve been away for so long; it’s been real busy ’round here, and like my Pops always says, you gotta make hay while the sun shines.  But… there’s only so farming you can do without yr back giving out, so I’m taking a little break to re-stock Ye Ole Country Store (aka Blog) with piles of new stuff.  Been a good coupla weeks at the flea market, annoying camera-crews aside (see my Tumblr for details).  Recently picked up a very large collection of circa 1950 DIY Electronics publications, and I’ve culled the cream-of-the-crop for y’all: some still-useful audio projects, and lots of interesting but forgotten bits and bobs from the pre-transistor era.  Schematics and project notes on some unique amplifiers, preamps, and even a novel compressor design that promises some unique sounds.  I’ll be posting a dozen or so of these pieces over the next couple of weeks; in the meantime, here’s a quick visual sampler of what yr in for.

Categories
Microphones

Sank Comes Thru Again

Wanna take a second here to say “thanks” to Stephen Sank, again, for his sagacity in the service of my old ribbon mics.  My circa 195X RCA BK5b is one of the most popular (with vocalists) in my pile/collection of mics and it gets used a lot on sessions… and it breaks every couple of years.  Pretty consistently.  Luckily there’s a reliable, experienced, and reasonably-priced serviceman who really knows his way around these dusty old gems.  I was afraid that the ribbon had broken and/or fried, yet again, but that was not the case.  From S:

“Very bizarre problem, very easily dealt with.  I have never, ever seen it happen before on an RCA, but one of the transformer taps went bad spontaneously.  Wire up into the potted transformer shield casing is fine, so it happened in the core.  Fortunately, the 150ohm tap is fine, so just moved a wire to it.  Works great, ribbon still perfect.  And there is no reason at all to suspect any future transformer issues.  And that transformer is unbeatable & unobtainable, so don’t even ask.;-)”

Yeah it never would have occurred to me to suspect the transformer.  Anyhow my BK5b is back and should make another recorded appearance soon.  You can find Sank at this website.

Categories
Microphones

DONT TOUCH

DONT TOUCH

MY MIC

IF YOU WANNA SING SOME BGVS

FINE, GIT YR OWN GODDAMN MIC

THE BOX STAYS LOCKED WHEN REH IS OVER

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Fairly high-up on the list of ‘unnecessary shit that i prolly shouldn’t have bought‘ is this mint-condition Peavey PVM-38 microphone.   But what an incredible artifact, innit.  Consider what kind of paranoid, uptight culture could have created a shitty low-cost microphone that includes a military-grade locking hard-shell case, thus allowing access to only the key-holder.  Exactly who/what is this case designed to protect/prevent?  If you are concerned about the sanctity of your microphone, perhaps simply take it with you?  It is not so large/heavy as to preclude easy transport?  Rather, I feel like what we have here is the superimposition of two previously unrelated concepts: the microphone, on one hand, and an intense concern with property rights on the other.

I can’t tell you from whence this artifact originates, as there is little information online concerning its heritage, but Peavey Corp does offer this download (PVM_38i) regarding a very similar model; the date of that document is 1993.  I can vaguely recall seeing these mics for sale at the local mom+pop when I was a kid; late 80s, early 90s; and the box made a strong impression: at least to a child, the effect was ‘wow that must be a rad mic if such intense security surrounds it at all moments.’   The semantic chain here is the ever popular Security/indicates/Economic Value/indicates/Quality.   But then what happens when one learns that the object in fact has a low cost, as these mics no doubt did?  Do we still make an easy leap from Security to Quality?  Oh Peavey.  The mysteries you hold.

While the precise semiotic operation of the Peavey PVM38 and its associated flotsam (IE,, case+key) may remain a subject of debate, we can fairly readily assess the object’s quality.  Yup it’s time for yet another SHURE SM57 vs SOME UNPOPULAR OLD MIC test.  Here’s a single acoustic fingerpicked guitar performance; mics are positioned as shown above; levels are matched exactly.  No processing whatsoever was applied, other than digitally increasing the levels to full level.  The Peavey’s output is approximately 2.5 db hotter than the SM57.  Take a listen:

First, the SM57: ShureSM57_ref

..and now the PVM38: Peavey_PVM38

My $0.02: The sound is pretty similar.  The Peavey seems to have less boxiness/low mids, a pretty similar pickup pattern, and a little less accuracy/detail in the very high end.  Overall it has a bit of that ‘budget mic’ sound but the high output is a plus.   I would imagine that the PVM38 would probably make a decent live vocal mic for rock vocals, and probably good for under-snare as well.  Certainly worth the $15 that I paid.

Categories
Uncategorized

Interesting Binaural article from 1952

Download a nine-page piece first presented in 1952 by one Otto Bixler of the Magnecord Corporation.  Bixler describes Magnecord’s early work in the field of stereophonic recording and reproduction.

DOWNLOAD: BinauralRecordingSystem_Bixler

Thank you to a very helpful long-time contributor for sending this piece in.   This article was originally published right at the dawn on the stereo era, and it’s interesting to read some early speculation about the promise/usefulness that stereo sound offered.  I’ve been thinking quite a bit about stereo effects recently, as I picked up a Calrec Soundfield Mark IV earlier this season.    It’s currently being serviced, but look forward to some interesting experiments and reports on that exotic piece soon.

Categories
Synthesizers

Holy WTF

On eBay right now: a 1939 (no typo) RCA electric piano, the ‘Storytone.’  Seems similar to a Yamaha CP70 in principle.  But my lord would you look at this thing!

See this link for about a million photographs and alllll the details.  The Storytone has been fully restored; the price is a not-unreasonable $19k.  Or best offer.   BTW, the same seller has a ton of really incredible, really incredible, keys and chromatic perc instruments for sale.  Just when you think you’ve seen it all…

Categories
Uncategorized

Live DJ set this Wednesday October 3- New Haven CT

How y’all doin.  Been a little slow on the new material this week as I’ve been super busy in the studio workin on a exciting new record for a fine artist…  more to come on that.   Anyhow, wanna thank JBW aka SWAY for inviting me to join him behind the decks at Firehouse 12 in New Haven this coming Wednesday the 3rd.  We’ll be spinning from nine til one for their ‘UNSPUN’ party; i’m diggin deep into my collection of ye old rocknsoul for this one.  Expect loud drums and a whole lotta tambourine.  If you haven’t been to Firehouse 12, it is really a fantastic bar, great space, great libations.

Categories
Magnecord

Magnecord-Specified Album Circa 1955

If you’ve been following this website for some time, you’ll know that I’ve written a lot about the Magnecord Company and its products, especially the iconic PT6 (of which I own, and still use, two restored examples).  On PS dot com you can find many things Magnecord, from original catalogs to factory photos, company correspondence, issues of the corporate magazine, bios and stories from the original designer, and all the way up to contemporary recordings I’ve made with the machines.  NEways… reader RM sent us this interesting curiosity: a VOX-label organ recording of Bach’s Fugue In D-Minor which was apparently specially mastered to allow for ideal playback characteristics on Magnecord decks.  No idea if this indeed offered some special advantage in terms of fidelity or if it simply a marketing ploy?  Were these commercially sold as albums or were they a value-added bit when the machines were purchased?  Anyone?

Thanks R.M. !

Categories
Pro Audio Archive

ADM Mixers and Consoles of the 1970s and 1980s

Above: ADM console constructed for NYC’s A+R Recording c. 1976

Nice set for y’all today, courtesy of reader T.F.  T. sent over a large collection of ADM console images spanning the mid seventies into the 1980s.  I know next to nothing about ADM, other than it was very well-made equipment: discrete op-amps, UTC or similar-quality transformers, and inductor-based EQs are featured in many of their modules.  There’s not a tremendous amount of information on this kit online, but this guy always seems to have a few pieces of sale on eBay: both raw modules and P+P ready racked units.

Regarding the console pictured above, T. writes:

“it’s got the patented CRT spectrum graph option (left top) and it’s a Quad console, note the two panning joysticks on the upper right of the board. A&R made quad records for Project 3 with Enoch Light and some rock quad mixes were done there too. I have one of the ADM joystick panners, it was an interesting piece of machine work. 4 pots controlled by the joystick mechanism, driving VCA’s. All ADM consoles from the mid-70’s forward used their patented Slidex faders controlling VCA’s, nothing was done directly from the fader. In those days, you wanted to protect your console surface from spilled drinks and other substances. For what it’s worth, all the ADM stuff I have is on par with API, Harrison and Spectra of the same era. American design, different from Neve and the Brits.”

In the comments section at the end of the post (click ‘comments’), you can find some additional commentary from T.F. on the ADM brand and their products.

Scroll down for the rest of the photo set.  If anyone is currently using any of these modules for audio production work, drop a line and let us know yr thoughts.   And if you were involved with the ADM corporation, we’d love to hear a bit about the company; its origins, evolution, and current work of it’s principles/designers.

CIRCA 1976

ADM BC-5 Console

ADM console constructed for KDKA-TV, Pittsburg

Routing system constructed for NBC TV, NY

ADM NRC console

ADM console constructed for Teichiku Recording, Tokyo

ADM TV-32 Console

ADM Console constructed for WSB Radio, Atlanta

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CIRCA 1980

ADM 800 Series mixer

ADM 1600 Series mixer

ADM 2400 Series console

ADM 3200 Series console

ADM ST 160 console

ADM console constructed for KOMO TV, Seattle

ADM Automation system constructed for the Voice Of America

ADM Console constructed for WJZ TV, Baltimore

ADM console constructed for WTLV-TV, Jacksonville

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CIRCA MID 1980s

ADM BCS Series console

A later routing system constructed for NBC

ADM ST-164 radio console

ADM console constructed for the U.S. House of Representatives