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UltraSonic Rx Damping Instruments help to bring out the microdynamic speed, linearity, and detail of your source material. Besides reducing microphonic anomalies, Rx allows a freer musical flow, curing a harsh and stealthy "electronics factor" or "dryness" that ultimately ails even some of the most finely honed audio systems. Your tube gear will achieve a fluid, dynamic musical potential like it was engineered to do.
Mildly spring-tempered titanium C-ring holds three modified PTFE isolation pads. Each pad holds a specially formulated polymer O-ring against the tube glass.
Herbie's most popular damping instrument, UltraSonic Rx is appropriate for all audio vacuum tubes, handling radiant heat up to a constant 482° F (250° C).
UltraSonic Rx-Mini: For sub-miniature and Nuvistor tubes approximately 3/8" diameter (9.2mm to 10.4mm), including 5703, 6111, 6112, 6020, 6021, 6088, 6CW4, 6DS4, 6DV4, 6N16B, 7586, 7587, 7895, 8056, 8058, T3 bulb.
UltraSonic Rx-7: For 7-pin miniature tubes and all tubes approximately 5/8" to 3/4" diameter (16mm to 19mm), including 0A2, 0B2, 0C2, 1S5, 12AE6, 12FK6, 12FM6, 12X4, 304B, 3A5, 3S4, 403A/B, 408A, 5591, 5651, 5654, 5654SQ/W, 6005, 6186, 6AK5, 6AK5W, 6AL5, 6AN4, 6AQ5, 6AQ6, 6AU6, 6BH6, 6C4, 6ER5, 6FG5, 6FQ5A, 6FS5, 6FY5, 6GK5, 6J1, 6J1P, 6J1P-EV, 6J6, 6N4, 6P17, 6X4, 6Z4, 7543, 9001, DCC90, DL92, EC90, EF95, M8100, OA2, OB2, OC2, SBA6. (Most 7-pin miniature tubes, at about 19mm diameter [3/4"], can also use UltraSonic 9.)
UltraSonic Rx-9: Fits miniature 9-pin tubes and all tubes 3/4" to 7/8" diameter (19mm to 22mm), including 10GV8, 12AT7/ECC81, 12AU7/ECC82, 12AV7,12AX7/ECC83, 12AY7, 12AZ7, 12B4, 12BH7, 12BY7, 12BZ7, 12DW7, 12FQ7, 2C51, 396, 396A, 417, 5670, 5687, 5751, 5755, 5814, 5842, 5879, 5963, 5965, 6072, 6189, 6201, 6267, 6350, 6385, 6414, 6519P, 6688, 6829, 6840, 6922, 6955, 6973, 6AN8, 6BL8, 6BM8/ECL82, 6BQ5/EL84, 6AW8, 6AW8A, 6BQ7, 6BZ7, 6BW4, 6C19P, 6CA4, 6C45, 6CG7, 6CS7, 6DE7, 6DJ8/ECC88, 6E5P/6E5PI, 6EJ7, 6EU7, 6FQ7, 6GC7, 6GF7A, 6GH8(A), 6GU7, 6GW8, 6H23N, 6H30, 6H6PI, 6N1P, 6N2, 6N2P, 6N23P, 6N30, 6N30P, 6N3P, 6N6/6H6PI, 6N6P, 6P1, 6P1P, 6P1P-EV/6II1II-EB, 6S19P, 6S4, 6U8(A), 6V4, 7025, 7044, 7058, 7062, 7119/E182CC, 7189, 7199, 7308, 7788, 7AU7, 7DJ8, 8416, CCa, D3a, E288CC, E80CC, E80F, E88CC, EC86, ECC189, ECC40, ECC802S, ECC803/S, ECC81, ECC82, ECC83, ECC85, ECC86, ECC99, ECF80, EL821, ECL86, EF184, EF800, EF86, EL821, EL84, EL86, EM84, EZ80, EZ81, M8162, PCC88, PCL82, PCL86, SV83, (T-6 1/2 bulb).
UltraSonic Rx-25: Fits all tubes approximately 1" to 1-1/16" diameter (23mm to 28mm), including metal 12SC7, 5693, "slim" 5Z4, "slim" 6AU4, metal shell 6F6, 6J5, 6R7, metal 6SC7, metal 6SJ7, "slim"6SN7, metal 6V6, 6X5.*
UltraSonic Rx-30: Fits narrow, straight-sided octal tubes and all tubes approximately 1-1/8" to 1-1/4" diameter (28mm to 32mm), including 0A3A (straight-sided), 1266, 12AX3, 12J5/GT, glass 12SJ7, 12SJ7GT, 12SL7/GT, 12SN7/GT, 3CM, 437A, 4P1L, 5691, 5692, 5852, "slim" 5AR4 (G.E., Sovtek/Reflektor, T-9 bulb), 5Y3, 5Y3GA, 5Y3GT, "wide" 5Z4, 6106, 68HC, 6AH4, 6AU4GT, 6AU4GTA, 6AU5, 6AX4GT, 6AX4GTA, 6AX4GTB, 6BL7, 6C5S, 6CJ3, 6D22S, 6DA4/6DA4A, 6DN7, 6EA7, 6EM6, 6EM7, 6EW7, straight-sided 6F6G, 6FD7, 6FM7, 6FY7, 6H4GT, 6J8P, 6K11, 6L6, 6N8P, 6N9P, 6R7GT (glass T-9 bulb), 6SC7 (glass tube), 6SF5-GT (glass tube), 6SH7, glass 6SJ7, 6SJ7GT, "slim" 6SL7, 6SN7, 6SN7GT-series (6SN7GT, 6SN7GTA, 6SN7GTB, 6SN7WGT, 6SN7WGTA), 6V6, 6V6GT (GE, Sylvania, Tung-Sol), 6X5G/GT/WGT, 6Y6, 7355, 7591, 7868, 7N7, C3G, C3M, EC8020, "narrow" EL34 (E-H, Mullard, SED "Winged C," Siemens, Svetlana, Telefunken, NOS Tesla, Tung-Sol), EL34/6CA7 (Svetlana), EL34B (Tung-Sol), GZ30, MT8 bulb, PL504, OA3A (straight-sided), T-9 bulb, VT-231.*
UltraSonic Rx-35: Fits standard, straight-sided octals and all tubes approximately 1-5/16" to 1-7/16" diameter (33mm to 36mm), including 5AR4 (Amperex, G.E., Japanese "Mullard" copy, Mullard, JJ, Shuguang), "slim" 6CA7 (Tung-Sol), 6H6, standard 6L6/5881, 6L6B, 6L6GT, 6L6WGB, 6SF5 (metal shell), 6V6GT (RCA), 6V6S (JJ), E34LS, ECC33, medium-diameter EL34 (Amperex, Philips, JJ, some Mullards, Valvo), EL34B (Shuguang), GZ34 (GE, JJ, Mullard, Philips, Raytheon, RCA), KT77.*
UltraSonic Rx-40: Fits wide and bottle-shaped octals and all tubes approximately 1-1/2" to 1-5/8" diameter (37mm to 44mm), including 0A3 (bottle-shape), 0C3, 0D3, 1626, 19, 27, 30, 37, 3DG4, 520B (near bottom of tube), 5881, "fat-bottle" 5AR4 (Amperex, Mullard, T-11 bulb), 5AW4, straight-sided 5R4-types, straight-sided 5U4 and 5U4-GB (T-12 bulb), 5V3, 5V4, 5Y3GB, 5Y4GA, 5Z4G, 5Z4P, 6080, "slim" 6550, straight-sided 6AS7, 6BY5/G/GA (straight-sided), 6C6, 6C8G, "Big Bottle" 6CA7 (E-H, GE, Sylvania, etc.), "Black Bottle" 6CA7-Z, 6F8G, 6HB5, bottle-shape 6J5 (ST-12 bulb), 6JN6, 6L6GC(E-H, Mazda, JJ, GE, RCA, Sylvania, Tungsol), 6L6WGC, 6LF6, 6P3P, Sophia Electric "bottle" 6SL7 and 6SN7, 7027/A, 7236, 76, 84, 8417, 85, CV3798, "Fat Bottle" EL34 (Big Bottle), EL509, G75/2D, straight-sided GZ32, "slim bottle" GZ37, KT90, OA3 (bottle-shape), OC3, OD3, PL509, QS150/40, VR105, VR75/30, VR75/40.*
UltraSonic Rx-50: For all tubes approximately 1-3/4" to 2-1/8" diameter (45mm to 54mm), including 10Y, 101F, 1610, 2A3 (Brimar, E-H, E-H Gold, RCA, Sovtek, Sylvania, Tung-Sol), 26, 274B (Western Electric), 307A, 35, 350B, 3A/110A, 3A/110B, 3D21A, 421A, 422A, 45 (RCA, Sylvania, TJ, Tung-Sol), 46 bottle-shape, 572-10, 5998, bulb-shaped 5R4-types, 5R4WGA/B (Tung-Sol), bottle-shape 5U4G, 5V4, 5Y3G (Sylvania), 5Z3, 5Z3P/A, 5Z4G (Brimar), standard and wide 6550 (E-H, GE, Philips, RCA, SED, Svetlana, Sylvania, Tung Sol), 6550A, 6550C, bulb-shape 6AS7, 6AS7G, 6B4, 6B4G, 6BY5/G/GA (bottle-shape), 6CA7-Z, 6C33C (upper portion of tube), bulb-shape 6F6G, 6H13, 6H13C, bulb-shape 6L6G, 6N13P, 6Y6G, 71A, 80 bottle-shape, 801/801A, 807, straight-sided 811, 814, C327 ("bulb" 27), CX4, bottle-shaped octals like AZ4, CV181/ECC32, CV181TII (Psvane 6SN7), CV181-Z (Shuguang), CV378 (Mullard), EL156, EL37, bottle-shaped GZ32 (Mullard), GZ33, KT120, KT66, KT88 (E-H, EAT, GEC, Gold Lion/Genalex, JJ/Tesla, SED, Shuguang, Sovtek, Svetlana), PX4, ST-14 bulb, ST-16 bulb, U52.*
UltraSonic Rx-55: For jumbo-size tubes 2-3/16" to 2-5/16" diameter (55mm to 59mm), including 101D/101F, narrow 211 (RCA), 211/VT-4C (GE), 2A3 (EML), 2A3-Mesh (EML), 274A, 300B "Balloon" (KR), Svetlana 300B, Takatsuki TA-300B, 45 (EML), 46 globe-shape, large bottle 5Y3GB (smaller Mazda uses UltraSonic 40), 80 globe-shape, "narrow" 805 (RCA, United), 829B, 841, 842, narrow 845 (Amperex, RCA), 845A (Shuguang), 872, GE211, "Big Bottle" GZ37, KT150 (specify size "60" in comments section of order form), SV811-10, ST-17 bulb, T-18 bulb.*
UltraSonic Rx-65: With plenty of flex to accomodate a wide range of tube diameters, fits giant tubes from 2-3/8" to 3" diameter (60mm to 76mm), including 101D "tennis ball," 101J, 102B, wide 211 (Sophia, TJ), 274B (EML, Shuguang, Sophia, Valve Art), 2A3-40W (JJ), 2A3 Meshplate (Sophia, TJ), 2A3 Globe Meshplate (Sophia, TJ), 2A3C (Shuguang), 300B (AVVT, E-H, EML, JJ/Tesla, Sovtek, KR, TJ/Full Music, Western Electric), 300B-XLS (EML, KR), Meshplate 300B (EML, Golden Dragon, TJ, Sophia, Shuguang, Valve Art), 300B Globe Meshplate (Sophia, TJ), 32B, Globe 45 (TJ/Full Music/Sophia), 45C, 45N, EML 45-mesh, 50, 520B, EML 5U4G-Mesh & 5Z3-Mesh,6C33C (wide portion of tube), 803, "wide" 805 (Amperex, Shuguang, TJ), 811A, 813, wide 845 (Sophia, Shuguang metal plate, TJ), 845B (Shuguang), F2A, GM70, PX25, ST-18 bulb, ST-19 bulb, T-20 bulb.*
UltraSonic Rx-100: With extra-heavy-gauge stainless steel C-ring and four isolation pads, UltraSonic 100 dampers thoroughly tame microphonics in super-giant tubes 3-1/2" to 4-5/8" diameter (89mm to 118mm), including 833, KR T-1610 (Kronzilla), and tubes using T-36 bulb.
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