{"product_id":"royer-labs-sf24v","title":"Royer Labs SF24V","description":"\u003cdiv lang=\"en\"\u003e\n  \u003cp\u003e\u003cstrong\u003eRoyer Labs SF-24V\u003c\/strong\u003e is a stereo vacuum tube ribbon microphone — the pinnacle of Royer's SF series and the world's first commercially produced stereo ribbon microphone with tube electronics. Two matched 1.8-micron aluminum ribbon elements are mounted one above the other in a true coincident Blumlein configuration (crossed figure-eights, 45 degrees off axis), each driven through an independent tube circuit derived from the same electronics as Royer's TEC Award-winning mono R-122V. The tubes are JAN military-specification 5840W pentodes wired in triode configuration as cathode followers, burned in at the Royer factory before shipment. Output signals are transformer-coupled and galvanically isolated via Jensen transformers housed in the dedicated external power supply, which also contains the plate supply (135 VDC) and filament supply (6 VDC) sections.\u003c\/p\u003e\n\n  \u003ch3\u003eTube electronics — headroom, detail, and air\u003c\/h3\u003e\n  \u003cp\u003eThe triode cathode follower configuration eliminates typical tube coloration while retaining the advantages of thermionic technology: greater headroom and faster transient response compared to the FET-based SF-24. The higher output level comes entirely from the internal toroidal step-up transformers (free gain) — the tube circuit itself operates below unity gain and contributes no noise of its own; self-noise remains below 18 dB. Jensen transformers in the power supply provide galvanic isolation and output balancing, virtually eliminating induced noise on long cable runs. Active tube electronics maintain a constant, optimal impedance load on both ribbon elements regardless of the downstream preamp's input characteristics — the SF-24V works with any professional preamplifier without impedance matching concerns or overload risk. Output impedance is 450 ohms — higher than the FET SF-24's 200 ohms, a result of the transformer-coupled output stage.\u003c\/p\u003e\n\n  \u003ch3\u003eStereo configurations and mono operation\u003c\/h3\u003e\n  \u003cp\u003eThe Blumlein configuration — two figure-eights at 90 degrees — provides true single-point stereo capture with no inter-channel time-of-arrival delay to correct. Alternatively, the SF-24V operates in M\/S configuration with standard matrix processing in the console or DAW. Phase compatibility between the two channels is complete — stereo-to-mono summing produces no artifacts, which makes the microphone viable as a wide mono source when capturing performers with unstable positioning relative to a single-axis microphone. Each channel can be used independently as a standalone mono figure-eight microphone. The SF-24V ships with a dedicated external power supply, a 7-pin XLR cable, shockmount, and a handcrafted Padauk wood presentation case. Lifetime warranty to the original owner.\u003c\/p\u003e\n\n  \u003ch3\u003eKEY FEATURES\u003c\/h3\u003e\n  \u003cul\u003e\n    \u003cli\u003eWorld's first commercially produced stereo vacuum tube ribbon microphone\u003c\/li\u003e\n    \u003cli\u003eTwo matched 1.8-micron aluminum ribbons in Blumlein configuration (figure-eights, 45° off axis)\u003c\/li\u003e\n    \u003cli\u003eTwo independent tube circuits: JAN mil-spec 5840W pentode wired in triode configuration\u003c\/li\u003e\n    \u003cli\u003eTubes burned in at Royer factory before shipment\u003c\/li\u003e\n    \u003cli\u003eTube electronics derived from TEC Award-winning R-122V\u003c\/li\u003e\n    \u003cli\u003eGreater headroom and faster transient response than FET SF-24\u003c\/li\u003e\n    \u003cli\u003eSensitivity -38 dB — condenser microphone output level\u003c\/li\u003e\n    \u003cli\u003eSelf-noise below 18 dB — free gain from toroidal transformers, no noise from tube stage\u003c\/li\u003e\n    \u003cli\u003eJensen transformers in power supply: galvanic isolation and balanced output\u003c\/li\u003e\n    \u003cli\u003eConstant optimal ribbon load impedance regardless of preamp\u003c\/li\u003e\n    \u003cli\u003eSupports Blumlein and M\/S configurations from a single mic position\u003c\/li\u003e\n    \u003cli\u003eFull phase compatibility — stereo-to-mono summing without artifacts\u003c\/li\u003e\n    \u003cli\u003eEach channel independently usable as a mono figure-eight microphone\u003c\/li\u003e\n    \u003cli\u003eRibbon elements protected from phantom power, electrical transients, and miswired cables\u003c\/li\u003e\n    \u003cli\u003eDedicated external power supply (135 VDC plate \/ 6 VDC filament)\u003c\/li\u003e\n    \u003cli\u003eHandcrafted Padauk wood presentation case; lifetime warranty\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch3\u003eTECHNICAL SPECIFICATIONS\u003c\/h3\u003e\n  \u003cul\u003e\n    \u003cli\u003eAcoustic operating principle: electrodynamic pressure gradient with vacuum tube electronics\u003c\/li\u003e\n    \u003cli\u003eVacuum tube: JAN mil-spec 5840W pentode, triode-wired cathode follower\u003c\/li\u003e\n    \u003cli\u003ePolar pattern: crossed figure-eights (Blumlein)\u003c\/li\u003e\n    \u003cli\u003eGenerating element: 1.8-micron aluminum ribbon\u003c\/li\u003e\n    \u003cli\u003eFrequency response: 30–15,000 Hz +\/- 3 dB\u003c\/li\u003e\n    \u003cli\u003eSensitivity: -38 dB (re. 1V\/Pa +\/-1 dB)\u003c\/li\u003e\n    \u003cli\u003eSelf-noise: below 18 dB\u003c\/li\u003e\n    \u003cli\u003eOutput impedance: 450 ohms @ 1 kHz\u003c\/li\u003e\n    \u003cli\u003eRecommended load impedance: 1,500 ohms or greater\u003c\/li\u003e\n    \u003cli\u003eMaximum SPL: above 130 dB\u003c\/li\u003e\n    \u003cli\u003eMicrophone output connector: XLR 7-pin (stereo)\u003c\/li\u003e\n    \u003cli\u003ePower supply output connectors: 2x XLR 3-pin\u003c\/li\u003e\n    \u003cli\u003ePower requirements: plate 135 VDC @ 2 mA; filament 6 VDC @ 150 mA (dedicated PSU)\u003c\/li\u003e\n    \u003cli\u003eSupply current: 4 mA per channel\u003c\/li\u003e\n    \u003cli\u003eMicrophone dimensions: 270 mm x 39 mm (base) x 25 mm (top)\u003c\/li\u003e\n    \u003cli\u003eWeight: 583 g (20.5 oz)\u003c\/li\u003e\n    \u003cli\u003eFinish: Dull Satin Nickel; optional Optical Black\u003c\/li\u003e\n    \u003cli\u003eIncludes: SF-24V microphone, dedicated power supply, 7-pin XLR cable, shockmount, Padauk wood case\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Royer Labs","offers":[{"title":"Default Title","offer_id":53669833638225,"sku":"28596","price":6138.91,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0729\/8741\/0769\/files\/RoyerLabsSF24V1.jpg?v=1778493523","url":"https:\/\/wrdtunes.com\/de-fr\/products\/royer-labs-sf24v","provider":"Wired Tunes","version":"1.0","type":"link"}