RCA PA system heads of the 50s/60s are one of the best values in antique tube equipment. I’ve bought a few on eBay in the $100-range and with a little work you can have a really great studio amp for gtr or bass. Sometimes they even come with the microphone input transformers…
Download the fifty-page 1940 PRESTO RECORDING CORP catalog:
DOWNLOAD (part 1): Presto_1940_Cat_1
DOWNLOAD (part 2):Presto_1940_cat_2
Products covered, with text, some specs, and photos, include: Presto Model A, Model B, Model F recording installations; Presto Model C, Model Y, and Model K portable recorders; Presto type 8-A, 8-B, 28-A, 6-D, 6-E, 6-F, 26-B, 75-A, 75-B, 75-C, 9-A, and 9-B recording turntables; Type 62-A transcription turntable; Automatic Equalizer 160; blower system 400; 150 and 151 pickups; Microphone Mixer type 130-A, B, C; Preamplifier type 40-A and 40-B; Presto radio tuner 50-A and 50-B; Recording Amplifiers 85-A, B, 85-E, 87-A and 87-B; plus a range of parts and accessories including Green Seal discs, Orange Seal discs, and Blue Label discs.
Above, the Presto Model A, their top-of-the-line system circa 1940.
Presto Recording Corp was a pioneer of coated-disc ‘Instantaneous Recording.’ From 1933 through the end of WWII, Presto was the US leader in providing high-quality recording equipment to broadcasters, schools, studios, and government. There is a detailed history of the Presto Corp provided at this website, so no need to re-tread those waters. Basically, what Presto offered was a way to make good-sounding LP and 78 recordings that could be played back instantly on any home turntable. Unlike earlier commercial recording technologies, there was no intermediate submaster required. Presto was able to do this by having designed an aluminum (later, glass) disc that was coated with a special cellulose-based compound (featuring 51 ingredients!).
At right, the Presto 200-A Electronics package. This was a complete system of microphone preamps, cutting amps, patchbay, and AM radio tuner that was designed to accompany the Model-A pictured above. Presto’s ‘instant-disc’ technology was basically rendered obsolete by the development of magnetic tape recorders in the late 1940s, most notably, AMPEX (and to lesser degree, Magnecord). The specs for the better Presto systems weren’t awful: 50-8000hz frequency range, 50db signal-to-noise ratio; but this paled in comparison to the German Magnetophon technology that AMPEX built on, with a high-frequency response to 15,000hz.
On a more basic user-level: you could always record-over a piece of magnetic tape; but cutting into a lacquer-coated disc (at $16/unit in today’s money) was a commitment.
Presto Model C, their top-end portable system of 1940 ($20,000 in 2011 dollars; 138 lbs)
Looking through this catalog, the most fascinating aspect is the large range of mechanical devices and accessories recommended to insure the fidelity of the audio. Nowadays almost all audio control happens electronically; once the room is treated and the microphone carefully placed, our work as recording engineers leaves the realm of physical manipulation and enters a world of electronic control. In the era of analog disc recording, though, a careful recording engineer needed blowers…
…to efficiently remove the bits of cellulose material that the cutting needle carved out the the recording blanks;
viscous-oil-filled dampers to regulate vertical movement of the cutting head (a mechanical audio compressor, I would imagine);
…an optical microscope to examine the grooves that you just cut for quality-control purposes…
fresh sharp needles to do the actual cutting work…
and, if you wanted the ultimate in convenience, an ‘automatic equalizer’ to automatically boost the treble frequencies as the cutting head moved closer to the center of the disc (since discs spin at a constant rate, as the needle gets closer to the center of the disc, the actual linear speed of the needle relative to the surface medium gets slower, and as we know well in all types of analog recording, slower equals less high-end).
Above, the Presto 40-A microphone pre-amplifier, the one piece of equipment in this lengthy catalog that could still be of potential use to modern recordists. It uses two 1221 tubes to deliver 55dbs of gain (from what I can gather, 1221s are interchangeable with 6C6, the 6C6 being the predecessor to the 6J7, likely making these 40As likely very similar to RCA BA1/2/11 series mic preamps). If anyone has the schematic to the Presto 40 mic preamp, please send it to us… coincidentally I built a preamp with 6C6s a few years ago (based on a schematic from an ancient UTC catalog) and I liked the results.
UDPATE:
Thank-you to reader EL for sending us the schem to the Presto 40-A. Here ’tis as a download: PRESTO Type 40-A preamp schematic
…And here as well:
This must be a slightly later version of the 40-A, as the 2nd tube is a 6SJ7, which is a variant of the 6J7 that has the input grid connection in the base rather than on the top. Other things to note: the input transformer spec’d is an ‘LS-10,’ which I can only assume means the UTC LS-10… circuit-wise, we have the first 6J7 connected in pentode, coupled by a .1uf cap to the 2nd 6SJ7 stage, this time wired in Triode in order to more easily drive the output transformer. A ’50M’ resistor (or as we know them, 50K ohms) provides negative feedback from stage 2 to stage one. Thinking that this circuit could be nice as the back end to a 3-stage pre, maybe with a something low-gain like a 76 or 6J5 on the front end with a volume pot following.
UPDATE (2)
EL also provided some images of his particular 40A units… check ’em out…
Pretty amazing that these things made it all the way to Australia way back when… my lord can you imagine how much these things must have cost in their day?
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Update Sept 2013:
E.L. directed us to this eBay auction; a Presto 40a in nice condition (Nashville, TN) sold for $510. Here are some images:
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Anyone out there using any Presto equipment in their work? Drop a line and tell us about it….
UPDATE: a friend has alerted us to The 78 project, a series of new recordings of notable musicians made using just a Shure 51 mic and a Presto disc recorder. They sound great, and in the videos you can hear both the modern production-sound of the session via the camera audio-track and the actual 78 playback. Very interesting contrast…
For my non-technical readers: a phono preamp is a device which does two basic things: 1) it equalizes the program that the phono cartridge picks up off the LP record, basically by boosting the low-end and cutting the high end, with this action centered at the fixed frequency of 1K hz (for full details on the ‘RIAA compensation curve’, and why it is necessary in the manufacture of LP records, read here); 2) secondly, a phono preamp must amplify the signal of the phono cartridge to roughly line-level (IE., the level that would come out of a CD player or VCR) and also deliver this signal at a low enough impedance such that it can be in-put to any receiver or consumer amplifier that it might encounter. Here is my attempt at a self-contained version of the phono pre-amp section from the Marantz 7 hi-fi preamlifier.
I’ve never heard an actual Marantz 7c in action. Considering that this dude, who does not seem like a total flake (based on his sales record) is selling one for $4,999 on eBay, I had to assume that it sounds fine (at least). Marantz is one of the legendary American Hi-Fi brands from the ‘Golden age of Hi-fi,’; their original line-up of products (before Saul Marantz sold the company) are widely lauded for both their sonic and aesthetic traits (see here for previous Marantz coverage on PS dot com).
Above, the schematic that I used for this build. It is a simplified version of the Marantz 7C, omitting such features as pre-RIAA disc compensation curves and bass/treble controls (for the complete 7C schematic, see here). The only change that I made to the audio section is that I added a 1K resistor between the signal output (the .47 cap) and the output jack. Couldn’t hurt, right? The phono pre-amp section consists of the three triode stages that you see at the left. The three stages to the right are additional make-up gain that follow the overall balance and volume controls. Important to note: the output of the phono stage is a cathode follower. This means that the signal is derived from the cathode of the tube rather than the plate. This results in very little voltage gain (in that particular stage) but… also… pretty low impedance. Which is what I wanted.
Above, the RCA RIAA phono preamp as published in several of their “Receiving Tube Manuals.” I have built this RCA circuit before; while excellent-sounding, it does require an additional stage of amplification (I used a cathode follower circuit) to lower the output impedance of the device if you want to be sure it will ‘play-nice’ with all yr other kit.. Notice the note at the output leg of the circuit: “220000 ohms minimum.” Wow! That is very high impedance. The only devices that this thing should feed are either the grid of another tube or possible a FET. This condition makes the RCA circuit (on its own) insufficient as a stand-alone device. And RCA did not really intend this to BE a stnd alone device; rather, they intended that you would build this into an amplifier where the circuit could directly feed the input grid of a preamp tube. The Marantz 7c circuit, with it’s third cathode-follower stage, does not have this limitation.
Above, the interior of the completed piece (audio chassis). Note the French SOLEN coupling caps (my favorite due to good performance, reliability, and small size) and single ground buss (the piece of copper that runs along the lower edge). RCA used the single ground buss technique in most of their broadcast equipment, and AFAIK, this grounding style cannot be beat for performance and ease of manufacture.
Above, the interior of the power supply. I built the unit into two seperate chassis: audio and power supply: this was an aesthetic preference of the customer, and it also makes good sense when you are dealing with the miniscule audio voltage that emanate from a phono cartridge. Sure enough, the finished piece exhibits no (z-e-r-o) hum whatsoever. I did not follow the Marantz 7C schematic for the power supply; I just built what I though was neccessary: a DC supply for the filaments and a B+ chain with 4 stages of filtering (no choke). I used an NOS RCA power transformer that was a lil’ bit too exuberant for the 280V B+ requirement, hence the large-ish 15k ohm resistor near the bottom (the Marantz 7c schematic called for a 3.9k ohm in this position). When all was said and done, after experimenting with a three different resistors in this position, I was within 1% of the voltages specified in the schematic.
So how does it sound? Very good. Compared to the RCA phono pre, it rejects WAY more RF; it is very rich, extremely quiet, and the low-end response is so, so much better than the phono pre amps that come built into modern stereo receivers. I QC’d the piece with a good cartridge and a clean pressing of TUSK and it was “as Lindsey Buckingham intended it to be heard.” If you are thinking about making a tube phono preamp, give this one a try; build cost is very low and it went together very fast with no hassle.
Four-page article from the popular press circa 1960 which claims to describe the work of a recording engineer of the day. “Three complete stereo channels with a fader for each finger!”
Images of women as depicted in high-fidelity guidebooks circa 1960. These sort of publications generally deal in DIY advice, schematics, and ‘buyers guide’ segments. There is a lot of floor-sitting, demure outfits, and distant-gazing. There is an uncanny similarity to many of these photographs. Or as E puts it: ‘WTF. They all look like cats.’ Yeah that pretty much says it.
On rare occasion, we are shown women in more active (IE., less decor) roles. Here are a couple of examples: the (potential) technician and the shopper.
Legendary pop/RnB session drummer Bernard Purdie was apparently the distributor (!) of the MPC line of electronic drums. Purdie is best know for inventing the distinctive shuffle groove that would later appear in hits such as ‘Rosanna’ by the group Toto. He also replaced Pete Best’s drumming on an early US-market Beatles release. “But you wanna know something else?” This man loves life. Check it…
A few electronic-drumming odds and ends today from various issues of MUSICIAN magazine circa the mid 1980’s (see here for previous MUSICIAN mag coverage on PS dot com). Sampling drum machines, electronic drum kits, and live cymbal-effects processing were all new technologies at the time, and like all things 80s, they were delivered in a bright, bold, technology-YES manner. Put down that snare drum. Don’t be a square. Come on.
Simmons SDS8 electronic kit. “Our mission (is) to bring drums into the 80s.”
The Linn 9000 drum machine. Linn was the first company to make drum machines that played back ROM (read-only-memory) samples of actual recordings of acoustic drum hits rather than simply triggering analog synthesis circuits that made ‘drum sounds.’ By the 1990s you could not buy a new analog drum machine, and the ‘Rompler’ drum machine was industry standard, but Linn was a true innovator at the time and these things were crazy expensive, making them relatively uncommon today.
Zildjian cymbal miking system circa 1987. Let’s say you are a family who has been making cymbals for, oh, 400 years. All of sudden this new technology (sampling, synthesis) comes along which COULD make your product obsolete. Better get in the game, buddy. Basically a set of electret-condenser mics that clip to cymbal stands combined with a small mixer with effect loops. “Flange your ride cymbal at the same time you add a slapback echo on your hi hats.”
And in case you were wondering what Digidesign was doing prior to Changing-The-World with its Pro Tools digital audio recording/editing/mixing/processing software/hardware systems, well, here you have it. Digidesign presents: Digidrums! New ROM chips that you can stick inside your drum machine and get news sounds outta them! Make your drum machine sound more like real drums! And 18 years later Digidesign gives us…. Beat Detective! Make the drummer sound like a drum machine! Man vs Robot, the epic battle unfolds so slowly…
Download the twenty-four page 1973 Peavey Electronic Sound Equipment catalog:
DOWNLOAD: Peavey_1973_catalog
Products covered in this catalog include: Peavey Musician amplifier head; Peavey Bass amplifier head; Peavey F-800G and F-800B ‘festival’ high-power amplifier heads; VTA-400 tube amplifier head (with 4x 6550 power tubes); Peavey Vintage model 110 watt combo amp; Peavey Deuce 2×12 combo amp; Peavey Standard amplifier head; Peavey PA120, Standard PA, and PA 400 boxtop-style public-address mixer/amplifiers; Peavey PA-6A and PA-9 console-style PA mixer/amps; and a full range of speaker cabinets include the Peavey 115, 212, 215S, 215, 610, 412, 215H, 11bS, 612H, 118FH, and 412S cabinets.
Oh that logo. So much has been said about that logo. Here it is, already firmly in place in 1973. It’s jagged, angular lines, amateurish lack of balance, and simple hi-con style seem to make it the granddaddy of all 1980s hair-metal graphic identities, and by extension, the graphic aesthetic of an entire youth subculture of the 1980s. Could this be? Or is it just a coincidence? Peavey did try a re-design in the 1990s, but came back to the ‘classic’ in short order.
Has there ever been a more disliked logo in the very image-conscious world of popular music? Does Peavey (the company or the man) realize this? And do (they/he) give a fuck? Maybe that’s the answer itself. Considering that Peavey Electronics began as the basement-industry of a high school kid, a self-taught kid who by age 24 would have his own factory in Mississippi, and less than ten years later the owner of one of the largest audio manufacturers in America, at a time when so much of the American electronics industry had fled this country for Asian manufacture: I think it’s safe to assume that yes this is a confident, proud man who flies this awful logo as if to say: this is me. and yeah i can get away with it. My amps are still gonna sell. Semiotically it exists somewhere at the intersection of the Freak Flag/Pirate Flag/Confederate Flag/American Flag. Complicated anyhow. Oh let’s add Texas flag to that as well. ( I know that Peavey is not based in Texas but how many people have you seen with Mississippi tattoos if you catch my drift).
Indeed. What is power. Is it an expression of man’s will to independence, his resiliency, his ability to triumph in the face of a difficult environment? Or is it simply his desire to dominate other men? It’s fascinating to note that in this lengthy catalog there are no guitar amplifers with less than 110 watts of power output. There are no amplifers with less than two twelve-inch speakers (or four ten-inch speakers). These are big amps. Only big amps. Peavey would eventually become (along with Crate) the standard-issue ‘small practice amp’ for kids and beginners in the 1980s, but there initial thrust was limited to these big, loud stage amps.
Above, the Peavey ‘Festival’ stacks of 1973. Tube-powered VTA400 at left, followed by the 4oo watt solid-state guitar and bass versions. I’ve owned and used several Peavey amps, but I have never plugged into a Festival. I will say this, based on my limited experience with Peavey amps: the solid-state circa 1985 Bandit 65 that I briefly used in high school was the the best-sounding solid state guitar amp that I have ever used. The distortion character was incredibly tube-like; really uncanny (my other amp at the time was an all-tube Fender Champ 12, so I did have some limited frame of reference). I later had one of those 2×12 dual-6L6/solid-state preamp combos from the 1970s; it sounded great in the room, probably due to the open-backed cabinet, but always fell short when close-mic’d.
Lately I’ve been noticing that folks are trying to get in the area of $400 for these old Peavey stacks; this is much more money that they were ten years ago, so I suppose the ‘vintage’ tag is getting attached to them finally. I’m not sure if anyone’s buying them; I don’t see as many bands live in clubs as I used to; if you’re a young band who has chosen to rock an old Peavey solid-state stack over a (vintage or modern) tube amp, drop us a line and let us know why. There’s nothing inherently better or worse about solid-state or tube amps; it’s purely a preference, a matter of aesthetics; the balance of favor has been with tubes for the past twenty years but that could certainly change someday.
Chicks go wild (in my mind)
Goddamn I am playing this bass real fast
My mom didn’t like her, but Ms Friedman was totally the best teacher
(We don’t want) your war
Someday they will realize.
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Download fourteen pages of electric guitars and amplifiers from the Kay Instrument catalog circa 1968:
DOWNLOAD: Kay_Elec_Gtrs_Amps_1968
Models on offer include: Kay K400, K401, K402, K403, K404, K405, K406, and K407 K400 series “Professional” deluxe solidbody electric guitars w/ vibrato; K365 Apollo II guitar; K370 top-end “Artist” guitar, K355 Titan II; Kay K326, K327, and K328 Vanguard II guitars; K 310, 311, and 312 Value Leader guitars; Kay K318 and 319 Speed Demon guitars; Kay K561, 562m 563, K6530, K585, K625, K6262, K659, K651, K682, and K683 hollowbody electric guitars; K5951, K5952, K 5921, K5922, K5923, K5924, K5925, K5926, K5935, K5917, K5918, and K5919 electric bass guitars; and a whole slew of forgettable solid-state amplifiers.
Kay Instruments (by this point, a division of the Seeburg Jukebox company) was, along with Harmony, one of the Chicagoland giants of mass-manufacture of musical instruments in America throughout much of the twentieth century. Their guitars tended to by a little flashier and a little worse-playing than those made by Harmony, but there are of course some notable exceptions. The late-60’s Kays in this catalog are some of the last American-built Kay-branded instruments to be sold, and they are not among the more collectible of the Kay oeuvre (for that, see for example the Kay Jazz II). Many of the instruments in this catalog are pretty common, the exceptions being the higher-priced 400 series and the kinda outrageously expensive K370. Anyone out there ever owned one of these?
