Building on years of expertise, the M-Audio engineering team conducted exhaustive research into signature microphones—and listened extensively to clean, vintage recordings—examining what gives the world’s best high-end studio condensers their ineffable qualities. They distilled the best characteristics of classic vacuum tube designs into a single world-class mic with M-Audio’s trademark value pricing.
When tweaking the Sputnik mic’s capsule, M-Audio’s design team worked closely with top Los Angeles recording engineers. In final side-by-side listening tests, these pros put it up against some of the world’s finest vintage mics costing many times more. In particular, many observed that Sputnik exhibited the coveted low and low-mid qualities of the Neumann U47 and the upper-mids and highs of the AKG C12—making it ideal for faithfully recording a wide range of sources including both male and female vocals. All agreed that Sputnik performed flawlessly for the most critical recording situations.
Sputnik’s combination of military-grade vacuum tube, ultra-sensitive 3-micron evaporated gold Mylar diaphragm, solid brass construction, and selectable cardioid, omni and figure-8 polar patterns makes it ideal for a wide variety of voices, instruments, and applications.
The Sputnik mic circuitry is designed around a military-grade 6205M vacuum tube—a diminutive pentode wired as a triode yielding output behavior like that of a perfect current source (making it tolerant of a wide range of load conditions). The tube operates at high voltages—allowing an enormous dynamic range—but with less heat dissipation than other designs. This means, in part, that users can easily hang this mic upside down or orient it upright without having to worry about overheating the capsule.
M-Audio also mounted the tube itself upside down to facilitate shorter connections that, in turn, make for more controlled impedance and less stray capacitance—a design trait shared by German mics like the revered Telefunken 251. The Sputnik also employs a socketless design eliminating the potential for impedance mismatch, signal deterioration and contact corrosion. Research shows that tubes go bad within the first 10 hours. We hand-pick military-grade tubes to ensure the highest specs, consistency and reliability, then burn them in for a week so users do not have to worry about changing tubes in the first place.
Sputnik’s Class A amplifier circuit is an all-discrete transconductance design based on thermionic studies by researchers at Harvard and the American Institute of Physics. The amp uses a classic cascade circuit to increase the gain-bandwidth product and eliminate the effects of parasitic capacitances, giving the system a wide frequency response. The resulting high output impedance makes the mic very tolerant of load conditions (it’s in the meg-ohm range so it acts like a perfect current source).
While the tube does all the heavy lifting, Sputnik’s head amp employs an n-channel depletion-mode JFET for biasing so users don’t get nasty artifacts like hum and crackle that are common to tube-only designs. In essence, the Sputnik’s tube circuitry delivers ultra-smooth harmonic detail and rapid response to signals with fast rise/fall times, thereby eliminating transient problems. The amp is quite linear and features graceful overload characteristics and an enormous dynamic range due to high-voltage operation. These qualities simply cannot be achieved with a standard transistor amplifier or one of the more common Class A tube designs.
Where many of today’s microphones cut corners with a metallized plastic backplate, the Sputnik features a precision-machined, solid brass backplate that yields much greater crucial rigidity, precise tolerances and faithful sonic reproduction. The Sputnik also boasts a dual-backplate design similar to the one that lends the AKG C12 its trademark open, airy quality. In addition, M-Audio tunes the backplate for optimal on- and off-axis frequency and pickup response, and pattern symmetry.
A microphone’s ability to capture detail owes primarily to the thinness and uniformity of its diaphragm. Sputnik’s durable mylar diaphragm is an impressive 3 microns thin—a spec that carries a much higher price tag in most other mics. M-Audio also uses a high-precision evaporated 24-karat gold process to coat it for conductivity—which yields a much more uniform result than the sputtered gold or sprayed-on processes used in many other mics. Here, too, this delivers higher precision and tolerance within and between Sputnik mics. The specs on Sputnik’s diaphragm and backplate are only possible using computer-controlled manufacturing processes in a state-of-the-art facility.
The Sputnik’s power supply features a sophisticated circuit designed to ensure optimal performance of the mic and audio signal path. It also features a voltage ramp-up when powered on in order to further extend tube life. As an added bonus, an automatic load-sensing circuit compensates for varying transmission line impedances, allowing users to run cables as long as 200 feet.
The Sputnik mic’s space-age “lollipop” design minimizes diffraction from the body, resulting in superior off-axis response. The body itself is durable solid brass with an attractive polished nickel finish.
The Sputnik mic is manufactured with a close tolerance of ±1.5dB across the entire frequency range. That means that any two or more Sputnik mics purchased at any time qualify as a matched set for stereo recording.
The Sputnik’s frequency response is 20Hz – 20kHz ±1.5dB; the sensitivity is 30mV/Pa (-30.5dBV) and the max. SPL at 0.5% THD is 132dB (or 142dB with the 10dB pad). It also features a low-frequency roll-off and multiple pick-up patterns (cardioid, omni, figure-8). Sputnik includes a professional shockmount, dedicated power supply, 7-pin mic cable, grounded IEC power supply and a custom flight case.
“M-Audio has been consistently proving that a world-class mic doesn’t have to cost thousands of dollars,” says Adam Castillo, marketing director at M-Audio. “With Sputnik, we looked closely at the mics that well-established working professionals use consistently for critical recording tasks, and we used that as our starting point. Our track record in using the latest manufacturing advances to make affordable studio technology enabled us to deliver one of the best microphones at any price.”
Sputnik is now shipping and carries an MSRP of $699.95.