Electro-Voice Model 636
A slim brass-bodied omnidirectional dynamic that E-V sold as the junior partner to its broadcast legend, and priced it to move.
Overview
The Model 636 "Slimair" turns up in old tape-recording columns the way a Shure 55 turns up in photographs of Elvis. It's simply there, in the background of a hundred home studios, church PA racks, and small broadcast booths. Electro-Voice built it as the smaller, cheaper sibling of the Model 655 Broadcast Dynamic, and the company said so. E-V's own catalog copy calls the 636 the "junior partner" of the 655, sharing most of that model's characteristics and a very similar design. That's a manufacturer's framing, not an independent verdict, but it shows where the 636 sat in the line.
The 636 is a genuinely slim microphone. E-V's literature lists the body at 1-3/32 inches in diameter and about 10 inches long. The company marketed that baton shape as a fix for staging problems, since a thin mike disappears into a PA setup in a way a fat one doesn't. One period writeup in Audio (November 1960, p.61) made the same point. It noted that the 636's baton design made it easy to hand-carry and that its slim profile let it blend unobtrusively into public-address stagings, with output levels, the magazine observed, equal to microphones several times its size.
The case is extruded brass with a satin chrome finish, and there was a gold-finish option as well. An acoustically treated filter grille handles the practical problems of close-miking. It reduces syllabic blasting and pops, and it cuts wind noise when the mike is used outdoors. E-V was explicit that the 636 would tolerate bad weather, temperature extremes, humidity, and corrosive conditions. That is the same Acoustalloy diaphragm story the company told across its dynamic line, and the reason so many of these survive in working condition today.
The pickup pattern is omnidirectional, becoming directional at high frequencies. E-V acknowledged this in its own literature. The dynamic element's after-chamber is vented and resonated to extend the low end. The mounting carries standard threads and includes an on-off switch. A self-contained line-matching transformer sits inside, with impedance adjustable by moving a single connection in the cable connector.
Frequency response is where the sources start to disagree. E-V's catalog copy for the 636 states 60 to 15,000 cps, essentially flat, and that figure appears in the company's stereo-matching advertisements as well. A period test writeup, the kind of hands-on report that ran in the tape hobby press, claimed the unit it measured exceeded the published spec. It came in flat by program standards (±2 dB) from 50 to 13,000 cycles with usable response beyond both ends. The same report flagged something unusual: most good microphones trade output for flatness, and this one reportedly managed both a high signal output and an excellent response curve. Treat the extended-range claim as one tester's result rather than a factory guarantee.
Price is the other story. E-V listed the 636 at $70 with a 20-foot cord in its 1955 introduction, according to a new-product report in Tape Recording (April 1955, p.40). By the time the chrome-finish catalog listings settled in, the number had crept to $72.50 less stand, with the 630, the rugged, shorter-range stablemate, at $52.50 and the flagship 664 cardioid at $82.50. E-V pitched the 636 and 630 together as a matched pair for stereo work, guaranteeing that any two units would be engineered to equal each other in frequency response, polar pattern, and overall sensitivity. That matching claim was the whole sales argument: buy two, skip the trial-and-error of placement, get predictable stereo. Whether the matching was as tight as advertised is hard to verify decades later, but the pitch is well documented in the company's period advertising.
The 636's practical appeal was always general-purpose work: public address, tape recording, speech and music pickup where a cardioid's rear rejection wasn't needed. It's not a studio vocal mike and E-V never sold it as one. It's an omni that happens to be slim, tough, and cheap enough that churches and schools bought them by the dozen. That's also why they're not rare today, and why the collector market treats them as a functional curiosity rather than a trophy.
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