Original UltraSonic Tube Dampers

Original UltraSonic:

An affordable alternative to Herbie's top-of-the-line Rx, original UltraSonic Damping Instrument with titanium C-ring delivers intricate detail and imaging, linear frequency response, highly faithful to the source components and audio system. Specially formulated modified Teflon isolation pads absorb micro-vibrations to provide a revealing soundstage with reduced grunge and glare. Imbedded fiberglass sleeves surrounding the pads enable a firm grip. For continuous use to 525°F (274°C), original UltraSonics are appropriate for all home audio vacuum tubes, including small-signal preamp, rectifier, and output power tubes.

The perfect power tube damper for budget-conscious systems.

Scroll down for size listings, from smallest to largest.

UltraSonic Mini

For sub-miniature and Nuvistor tubes approximately 3/8" diameter (9.2mm to 10.4mm), including 5703, 6111, 6112, 6020, 6021, 6CW4, 6DS4, 6DV4, 6N16B, 7586, 7587, 7895, 8056, 8058, T3 bulb.

UltraSonic Mini: $12.49 ea.

4 or more: $11.87 ea.

UltraSonic 7

For 7-pin miniature tubes and all tubes approximately 5/8" to 3/4" diameter (16mm to 19mm), including 0A2, OA2, 0B2, OB2, 1S5, 12AE6, 12FK6, 12FM6, 12X4, 304B, 3A5, 3S4, 403A/B, 408A, 5591, 5651, 5654, 6005, 6186, 6AK5, 6AN4, 6AQ6, 6AU6, 6BH6, 6C4, 6ER5, 6FG5, 6FQ5A, 6FY5, 6GK5, 6J1, 6J6, 6N4, 6P17, 6X4, miniature 6Z4, 7543, 9001, DCC90, DL92, EC90, EF95, SBA6. (Most 7-pin miniature tubes, at about 19mm diameter [3/4"], can also use UltraSonic 9.)

UltraSonic 7: $14.25 ea.

4 or more: $13.54 ea.

UltraSonic 9

Fits miniature 9-pin tubes and all tubes 3/4" to 7/8" diameter (19mm to 22mm), including 10GV8, 12AT7/ECC81, 12AU7/ECC82, 12AX7/ECC83, 12AY7, 12AZ7, 12B4, 12BH7, 12BY7, 12BZ7, 12FQ7, 2C51/396, 417, 5670, 5687, 5751, 5814, 5842, 5879, 5963, 6072, 6189, 6201, 6267, 6350, 6414, 6519P, 6688, 6829, 6840, 6900, 6922, 6955, 6973, 6AN8, 6BL8, 6BM8/ECL82, 6BQ5/EL84, 6BQ7, 6BW4, 6C19P, 6CA4, 6C45, 6CG7, 6CS7, 6DE7, 6DJ8/ECC88, 6E5P/6E5PI, 6EJ7, 6EU7, 6FQ7, 6GC7, 6GH8(A), 6GW8, 6H23N, 6H30, 6GU7, 6N1P, 6N30, 6N30P, 6N3P, 6N6(P), 6P1, 6S19P, 6U8(A), 6V4, 7025, 7044, 7062, 7119/E182CC, 7189, 7199, 7308, 7788, 7DJ8, 8416, D3a, E288CC, E80CC, E88CC, EC86, ECC189, ECC81, ECC82, ECC83, ECC85, ECC86, ECC99, ECF80, ECL86, EF184, EF86, EL84, EL86, EZ80, EZ81, PCC88, PCL82, PCL86, SV83, T6-1/2 bulb.

UltraSonic 9: $14.29 ea.

4 or more: $13.58 ea.

UltraSonic 25

Fits all tubes approximately 1" to 1-1/16" diameter (23mm to 28mm), including metal 12SC7, "slim" 5Z4, metal shell 6F6, 6J5, 6R7, 6SJ7, "slim" 6SN7, metal 6V6, 6X5.*

UltraSonic 25: $14.69 ea.

4 or more: $13.96 ea.

UltraSonic 30

Fits narrow, straight-sided octal tubes and all tubes approximately 1-1/8" to 1-1/4" diameter (28mm to 32mm), including 12J5/GT, 12SL7/GT, 12SN7/GT, 3CM, 5691, 5692, 5852, "slim" 5AR4 (G.E., Sovtek/Reflektor), T-9 bulb, 5Y3, 5Y3GT, "wide" 5Z4, 6106, 6AH4, 6AU5, 6BL7, 6CJ3, 6DN7, 6EA7, 6EM6, 6EM7, 6EW7, straight-sided 6F6G, 6FY7, 6H4GT, "slim" 6L6, 6N8P, 6N9P, 6R7GT (glass T-9 bulb), 6SF5-GT (glass tube), 6SL7, 6SN7, 6SN7GT-series (6SN7GT, 6SN7GTA, 6SN7GTB, 6SN7WGT, 6SN7WGTA), 6V6, 6X5G/GT/WGT, 6Y6, 7355, 7591, 7868, C3G, C3M, "narrow" EL34 (E-H, SED "Winged C," Siemens, Svetlana, Telefunken, NOS Tesla), GZ30, PL504, VT-231.*

UltraSonic 30: $14.95 ea.

4 or more: $14.20 ea.

UltraSonic 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, 6H6, standard 6L6/5881, 6L6B, 6L6WGB, 6SF5 (metal shell), E34LS, medium-diameter EL34 (Amperex, Philips, JJ, Mullard, Valvo), EL34B (Shuguang), GZ34 (GE, JJ, Mullard, Raytheon, RCA), KT77.*

UltraSonic 35: $15.49 ea.

4 or more: $14.72 ea.

UltraSonic 40

Fits wide and bottle-shaped octals and all tubes approximately 1-1/2" to 1-5/8" diameter (37mm to 44mm), including 0A3, 0C3, 0D3, 1626, 19, 27, 30, 37, 520B (near bottom of tube), "fat-bottle" 5AR4 (Amperex, Mullard, T-11 bulb), 5AW4, straight-sided 5R4-types, straight-sided 5U4 and 5U4-GB (T-12 bulb), 5V3, 5V4, straight-sided 5Y3GB, small-bottle 5Y3GB (Mazda), 5Y4GA, 5Z4P, 6080, "slim" 6550, straight-sided 6AS7, 6BY5/G/GA (straight-sided), 6C6, "Big Bottle" 6CA7 (E-H), "Black Bottle" 6CA7-Z, 6F8G, 6HB5, bottle-shape 6J5 (ST-12 bulb), 6JN6, 6L6GC (Mazda, JJ, GE, RCA, Sylvania, Tungsol), 6LF6, 6P3P, Sophia 6SL7, Sophia 6SN7, 7027, 7236, 76, 84, 8417, 85, "Fat Bottle" EL34 (Big Bottle), EL509, straight-sided GZ32, KT90, OC3, PL509, VR105.*

UltraSonic 40: $15.65 ea.

4 or more: $14.87 ea.

UltraSonic 50

For all tubes approximately 1-3/4" to 2-1/8" diameter (45mm to 54mm), including 101J, 1610, 2A3 (RCA, Sovtek, Sylvania, Tung-Sol, Brimar), 26, 274B (Western Electric), 307A, 35, 350B, 3D21A, 45 (RCA, Sylvania, Tung-Sol), 572-10, 5998, bulb-shaped 5R4-types, 5R4WGA/B (Tung-Sol), bottle-shape 5U4G, 5V4, 5Z3, standard and wide 6550 (E-H, GE, Philips, RCA, SED, Svetlana, Sylvania, Tung Sol), 6550A, 6550C, bulb-shape 6AS7, 6B4, 6B4G, 6BY5/G/GA (bottle-shape), 6C33C (upper portion of tube), bulb-shape 6F6G, bulb-shape 6L6G, 71A, 80, 807, straight-sided 811, 814, C327 ("bulb" 27), CX4, bottle-shaped octals like AZ4, CV181/ECC32, CV378 (Mullard), EL37, bottle-shaped GZ32, GZ33, KT66, KT88 (E-H, EAT, GEC, Gold Lion/Genalex, JJ/Tesla, SED, Shuguang, Sovtek, Svetlana), PX4, ST-14 bulb, ST-16 bulb, U52.*

UltraSonic 50: $15.95 ea.

4 or more: $15.16 ea.

UltraSonic 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, 2A3 (EML), 2A3-Mesh (EML), 274A, 300B "Balloon" (KR), Svetlana 300B, 45 (EML), large bottle 5Y3GB (smaller Mazda uses UltraSonic 40), "narrow" 805 (RCA, United), 829B, 841, 842, narrow 845 (Amperex, RCA), 845A (Shuguang), 872, GZ37, SV811-10, T-18 bulb.*

UltraSonic 55: $16.49 ea.

4 or more: $15.79 ea.

UltraSonic 65

Accomodates a wide range of tube diameters. Fits giant tubes from 2-3/8" to 3" diameter (60mm to 76mm), including 101F, 102B, wide 211 (Sophia, TJ), 274B (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), 520B, EML 5U4G-Mesh & 5Z3-Mesh, 6C33C (wide portion of tube), "wide" 805 (Amperex, Shuguang, TJ), 811A, 813, wide 845 (Sophia, Shuguang metal plate, TJ), 845B (Shuguang), F2A, GM70, PX25, ST-18 and ST-19 bulbs, T-20 bulb.*

UltraSonic 65: $16.95 ea.

4 or more: $16.39 ea.

UltraSonic 100

With extra-heavy-gauge stainless steel C-ring and four isolation pads, UltraSonic 100 thoroughly tames 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.

UltraSonic 100: $20.95 ea.

4 or more: $19.98 ea.

^*

Tube diameters and shapes sometimes vary. To estimate your tube diameter, just place a wooden or metal ruler against the side of your tube and "eyeball" the size – if you align your sight in a straight line to one edge of the tube and then in a straight line to the opposite edge, the measured difference in-between will be very close to the tube's actual diameter. Or measure the circumference and divide by pi (3.14).

Tubes are listed above by widest diameter of the bulb glass; on some bottle-shaped tubes, a damping instrument can be placed around the "neck" of the tube, where the neck meets the shoulder, allowing use of the next-smaller size damping instrument.

For tubes that fall in-between UltraSonic sizes, smaller size is the default recommendation (though either size will work). Tube size data indicates "maximum" tube diameter; tubes are often a little smaller than indicated. Titanium C-rings have some flex to them to accommodate variation in bulb diameters and can be bent to somewhat smaller or larger sizes.

Additional information, including bulb sizes, on most tube types and brands can be found here:

[ Frank's Electron Tube Data Sheets ]

inches millimeters

Changing gear? UltraSonic isolation pads can be slid off one titanium C-ring and onto another. If you need a different size than what you have, spare C-rings are available, so you don't have to buy a whole damping instrument to change sizes. Isolation pads are interchangeable among standard sizes (UltraSonic Mini thru 65).

Titanium C-Ring Only (no pads)
UltraSonic sizes Mini thru 65
$3.95 to $7.59 ea.
(4 or more, one size: 10% off)

Extra-Heavy Gauge C-ring
For UltraSonic 100
$8.49

(4 or more: 10% off)

UltraSonic Isolation Pad
from $3.49 ea.
(12 or more: 10% off)

90-day no-risk trial. If not satisfied, simply return any item within 90 days for a complete refund.

Lifetime warranty. If anything ever goes wrong, simply return any Damping Instrument to Herbie's Audio Lab and it will be repaired or replaced and returned to you at no cost.

With scant marketing and plain packaging, Herbie's Audio Lab offers low prices, high value!