Royer Labs R-122V is a monaural vacuum tube ribbon microphone with a dedicated external power supply — the pinnacle of Royer's R-Series line and the world's first commercially produced active vacuum tube ribbon microphone. The R-122V uses the same ribbon transducer assembly as the R-121 and R-122 — 2.5-micron aluminum ribbon (99.99%) with patented offset placement (Patent #6,434,252) and Neodymium magnets — but replaces the FET active circuit with a JAN military-specification 5840W vacuum tube in triode cathode follower configuration, coupled to a Jensen output transformer housed in the external power supply. Chronologically, the R-122V predates the R-122: research into the tube circuit was a prerequisite for developing the specialized toroidal transformer that later went into the phantom-powered FET R-122.
JAN 5840W tube — headroom and transparency without coloration
The triode cathode follower configuration is specifically designed to eliminate typical tube harmonic coloration — the R-122V is built for transparency, not for character. The higher output level comes entirely from Royer's custom toroidal step-up transformer (free gain) — the tube circuit itself operates below unity gain and contributes no noise of its own; self-noise remains below 18 dB. The high plate voltage (135 VDC) delivers headroom far beyond what a phantom power supply can provide — this translates directly into the ability to capture high-SPL sources without compression or distortion artifacts. The Jensen output transformer in the power supply provides galvanic isolation and output balancing, virtually eliminating induced noise on long cable runs. The triode cathode follower configuration is inherently resistant to HF loss over extended cable lengths — a practical advantage in orchestral and film scoring environments where the microphone-to-console distance is often considerable.
Patented offset ribbon and applications
The patented offset ribbon design (Patent #6,434,252) positions the ribbon closer to the front of the housing for higher SPL handling from the logo side and ribbon protection at maximum excursion. The rear side captures a slightly brighter response at approximately three feet and closer (phase reversed) — two distinct tonal characters from a single microphone. Active tube electronics maintain constant, optimal impedance loading on the ribbon regardless of the downstream preamp's input characteristics. Applications: electric guitar, brass, drum overheads and rooms, strings, woodwinds, piano, acoustic guitar, vocals; in classical recording as a spot microphone or in Decca Tree configurations; at distances of two to six feet from condenser spots, R-122Vs add dimensionality, warmth, and size to the recording. Lifetime warranty to original owner; 10-year tube warranty; first ribbon replacement free.
KEY FEATURES
- World's first commercially produced active vacuum tube ribbon microphone
- Same ribbon transducer as R-121 and R-122: 2.5-micron ribbon (99.99% Al), Neodymium magnets
- JAN mil-spec 5840W pentode in triode cathode follower configuration
- High plate voltage headroom (135 VDC) — unavailable from phantom power
- Sensitivity -36 dB — condenser microphone output level
- Self-noise below 18 dB — free gain from toroidal transformer, no noise from tube stage
- Jensen output transformer in PSU: galvanic isolation and balanced output
- Triode cathode follower: long cable runs without HF loss
- Constant optimal ribbon load impedance regardless of preamp
- 200-ohm balanced output
- Patented offset ribbon design (Patent #6,434,252) — high SPL front, brighter character rear
- Ribbon element protected from phantom power, electrical transients, miswired cables
- Dedicated external power supply (135 VDC plate / 6 VDC filament)
- Lifetime warranty; 10-year tube warranty; first ribbon replacement free
TECHNICAL SPECIFICATIONS
- Acoustic operating principle: electrodynamic pressure gradient with vacuum tube electronics
- Vacuum tube: JAN mil-spec 5840W pentode, triode-wired cathode follower
- Polar pattern: figure-8
- Generating element: 2.5-micron aluminum ribbon (99.99% Al)
- Magnets: rare earth Neodymium
- Frequency response: 30–15,000 Hz +/- 3 dB
- Sensitivity: -36 dB (re. 1V/Pa +/-1 dB)
- Self-noise: below 18 dB
- Output impedance: 200 ohms, balanced
- Rated load impedance: 1k ohm minimum
- Maximum SPL: above 135 dB @ 20 Hz
- Microphone output connector: XLR 7-pin
- Power requirements: plate 135 VDC @ 2 mA; filament 6 VDC @ 150 mA (dedicated PSU)
- Dimensions: 206 mm (L) x 25 mm (W)
- Weight: 300 g (10.9 oz)
- Finish: Dull Satin Nickel; optional Matte Black Chrome
- Includes: R-122V microphone, dedicated power supply, 7-pin cable, RSM-1 shockmount, mic sock, wooden case
