The Electro-Voice velocity microphones
Models V-1, V-1A, V-2, V-2A, V-3, and V-4
Seven images above show the Model V1, and are courtesy of Rick Green
V-1A microphone courtesy of Jeff Rudisill
V-2 microphone courtesy of Jeff Rudisill
A V-2 with its grilles removed
V-2A microphone courtesy of Jeff Rudisill
There was a V-2A. Dennis Schrank explains: “In the mid nineteen sixties Electro-Voice suddenly and quietly discontinued manufacturing ribbon mics. They replaced the ribbon element in the V-2A and V3 with an Acoustalloy Diaphragm. These elements can be found only on the very last runs of those two models. There is no way of knowing this from the outside of the mic. They are identical to the earlier versions including the label and velocity designation. But if you remove the cover the difference is obvious. If you are lucky enough to find one that is working properly, it is a really great-sounding mic. At least as good as the ribbon version with much higher output. Not many were made and they are quite scarce.”
Stephen Sank adds these observations: “This, if it was done by E-V, and I have seen enough V-2 and V-3 mics butchered in this way that I think E-V was actually responsible, was a dishonest and terrible thing to do to “repair” these mics. No matter how good the moving coil dynamic element is (and to my ears they are bloody awful), it’s still turning a ribbon velocity mic into a moving coil pressure mic, and, in my opinion, completely ruins the sound and value of these mics.
“So, anytime a V-2 or a V-3 comes up for sale anywhere, it’s completely hit or miss to know if you are buying a ribbon velocity mic or not, unless the seller provides a look inside. Sadly, since the entire motor structure is removed when these are turned into poor-quality moving coil mics, there is no way to reverse the process other than to install a motor from another mic.
“Fortunately, the V-1 ribbon motor’s pole pieces were part of the main casting of the mic, so they can be relied upon to still be ribbon mics, although virtually always high impedance. Incidentally, the V series E-V mics have the widest ribbons I have yet seen, at 0.2525 inch, which is quite a bit wider than the next widest, the RCA 44 series, which are 0.19 inch.
“Basically, I’d just like to reduce the number of times mic buyers get screwed in buying V-2/3 mics. Despite how cheaply the E-V ribbon mics were made, when properly ribboned, they can sound quite gorgeous (when low-Z or made to be low-Z), which was quite a surprise the first time I did one.
“Incidentally, here’s another piece of factual info about the V-2: The first V-2s were very different mics inside than most E-V V-series ribbon mics, in that they had a narrower ribbon (0.17 inch wide, same as the RCA Type 74-B), and a very different motor structure, comprised of a pair of horseshoe magnets screwed to each end of a pair of crude, straight-bar pole pieces, with the whole assembly spring-suspended from the interior frame.” See next image.
“The V-2A, rather than designating the aforementioned moving-coil conversion and downgrade, merely indicates the later, more commonly seen version of the E-V ribbon motor, as seen also in the V-1/V-3, with a single cylindrical magnet held behind a pair of flat-plate iron pole pieces, with welded tabs holding the magnet, and the huge 0.2525-inch-wide ribbon. The early V-2 model was a superior-sounding mic to the V-2A/V-1/V-3, but with quite lower output level caused by the much lower magnet mass and flux density, and the spring suspension was surprisingly effective at shock and handling-noise isolation.”
V-2 photo courtesy of Stephen Sank
Mr. Sank continues: “The shape of the lower body casing and label plate is the easy way to recognize one of these V-2s (as seen above), versus the straighter lines of the V-2A/V-1/V-3 housings. Also, the paint finish is wrinkle-textured, unlike the later mics.”
A close-up of a V-2A with its ribbon element having been replaced by a moving coil.
Description and Applications
The velocity microphone, also known as the “pressure gradient” type, responds to the difference in instantaneous sound pressure on the front and back of the moving element. The velocity microphone has a bidirectional pick-up pattern and an inherently flat frequency response. It is a type of microphone widely used in studio broadcasting and recording.
Electro-Voice velocity microphones are based on proven design and are extremely durable. The frame and internal mounting structure is a single piece, high-pressure die casting. Jars and mechanical shock cannot cause shifting of parts. This is an exclusive feature of all Electro-Voice velocity microphones. The microphone cradle is steel reinforced. Knurled knobs at the sides permit locking the microphone firmly in any position.
The pole pieces and magnetic assembly of Model V-1A are secured directly to the frame. The ribbon is of specially rolled material to provide high sensitivity and long life. The magnetic structure is so located as to provide most efficient utilization of the magnetic flux.
The open housing virtually eliminates internal reflection and diffraction. This assures full utilization of the velocity microphone’s high fidelity characteristic. True reproduction without imposed peaks and dips is the result of an efficient magnetic circuit and the Acoustalloy® diaphragm which provides a smoother response over a wider frequency range. Proper coordination of ribbon fabrication, pole piece design, magnetic circuit placement and correct transformer coupling provide a high fidelity response characteristic. The frequency response curve is ideally adapted to voice and music reproduction. Bidirectional polar pattern is shown in Figure 2.
It is an inherent characteristic of the ribbon velocity microphone that the output level is somewhat lower than that of a pressure microphone. Consequently, it is usually advisable to use the gain control on the amplifier in a correspondingly higher position. The velocity microphone retains its excellent frequency characteristic when used at distances of more than six inches from the sound source. When used at less than this distance, the microphone has a tendency to accentuate the low frequencies. This, however, may be desirable in certain instances… to compensate for associated equipment deficient in low frequencies or a voice that lacks depth, for example.
The bidirectional characteristic of the velocity gives equal pick-up at the front and back of the microphone, and zero pick-up at the sides, top, and bottom. Figure 2 indicates the output in decibels versus angle of pick-up. For all practical purposes the frequency response remains constant at all angles. The null or zero pick-up at the sides gives the velocity microphone the following advantages:
- Pick-up is increased 1.7 times over that of the conventional pressure microphone for average conditions of reverberation, acoustic feedback and room noise. For public address applications this pick-up range may be increased considerably through proper placement of speakers so that direct and reflected sounds strike the microphone at the null points (sides, top or bottom).
- Random room noise and reverberation are reduced 5 dB.
- The microphone may be placed so as to almost completely eliminate unwanted sounds.
- Acoustic feedback can be further reduced by tilting the microphone to place the null sides in the direction of the interfering sounds. See Figure 3.
- The microphone can be worked from both front and back simultaneously.
E-V velocity microphones are recommended for all types of music and voice reproduction… in public address, broadcasting and recording. Wide frequency response, high fidelity characteristics, wide-range front pick-up and pick-up range make these microphones ideal for solo or orchestra—for individual or chorus—for single speaker or groups. Very popular with singers and band leaders. Mounted in footlights or on overhead booms, they are used in reinforcing stage plays.
The Electro-Voice Model V-1A combines high-quality performance and extremely compact size. Frequency response is from 40 to 9,000 hertz. Output level is –63 dB. (0 dB = 1 volt/dyne/cm²)
The Model V-2 offers a choice of one standard impedance: Hi-Z, 50, 200, 250, or 500 ohms. Flat frequency response from 40 to 9,000 hertz. Output level is –62 dB. (Webmaster’s note: The V-1A, V-2 and the V-2A seen and heard on this page are Hi-Z versions. For the sound samples, each mic in turn was connected to a Shure Line Matching Transformer Model A95UF, feeding the low-impedance input to a tube mic preamp.)
Polar Pattern: Bidirectional voltage output proportional to cosine of angle of pick-up. For all practical purposes, the frequency response remains constant at all angles of pick-up. See Figure 2.
This information was obtained from Electro-Voice Technical Data Sheet No. 36.
Special appreciation is extended to Mr. Ethan Wetzell, E-V Technical Services,
for providing these specifications and for his encouragement.
The Electro-Voice V-3 with its impedance selector switch.
As it turns out, there was an Electro-Voice Model V-4 Velocity microphone.
Thanks to Ellis Dawson we now have this re-creation of the Model V series
Electro-Voice price list, which you can download as a PDF.
V-4 photos, voicing, and price list were provided by Ellis Dawson.
LINEUP—Our thanks to Ellis Dawson for this photo of his Electro-Voice models V-1, V-2, V-3, and V-4.
Download the Technical Data Sheet
for the V-1A, V-2A, and V-3 mics.