Tubes for the Ampeg B 12XT

Tubes for the Ampeg B 12XT

The Ampeg B 12XT amplifier requires the following components:

× 4
12AX7
12AX7
Vacuum Tube - 12AX7-A, Triode, Dual, High MU
Vacuum Tube - 12AX7 / ECC83, Mullard Reissue
Vacuum Tube - 12AX7A-C / ECC83, Tube Amp Doctor, Premium Selected
Vacuum Tube - 12AX7, Peavey
Vacuum Tube - 12AX7B, China
Vacuum Tube - 12AX7 / ECC83, Electro-Harmonix
Vacuum Tube - 12AX7LPS, Sovtek
Vacuum Tube - 12AX7WA, Sovtek
Vacuum Tube - 12AX7WB, Sovtek
Vacuum Tube - 5751, Triode, Dual, HI-MU
Vacuum Tube - 5751, Sovtek
Vacuum Tube - 7025, Triode, Dual, High MU
Vacuum Tube - 7025-WA, Tube Amp Doctor, High-Grade, Premium Selected
Vacuum Tube - 5751, JJ Electronics
Vacuum Tube - 12AX7S, JJ Electronics, Mid Gain
Vacuum Tube - 12AX7WC, Sovtek
Vacuum Tube - 5751, Tung-Sol Reissue
Vacuum Tube - 5751, Tube Amp Doctor, Premium Selected
Vacuum Tube - 7025, Tube Amp Doctor, High Grade
Vacuum Tube - 7025 S, Tube Amp Doctor, Premium Selected
Vacuum Tube - 12AX7, Tung-Sol Reissue - Regular
Vacuum Tube - 12AX7, Tung-Sol Reissue - Gold
Vacuum Tube - 12AX7 / ECC83, JJ Electronics - Regular
Vacuum Tube - 12AX7 / ECC83, JJ Electronics - Gold
Vacuum Tube - ECC803 / 12AX7, JJ Electronics, Long Plate - Regular
Vacuum Tube - ECC803 / 12AX7, JJ Electronics, Long Plate - Gold
Vacuum Tube - 12AX7 / B759, Genalex Gold Lion - Regular
Vacuum Tube - 12AX7 / B759, Genalex Gold Lion - Gold
Please make a selection above.
Miniature high-mu twin triode each section of which has an individual cathode connection - especially suited for use in resistance-coupled voltage amplifiers, phase inverters, multivibrators, and industrial-control circuits.

Russian-made Mullard Reissue 12AX7 dual triode. Large sound stage with excellent detail. Factory selected for low noise and microphonics. Great for hi-fi amps.

9 pin miniature preamp tube (Amplification Factor =100). Very good gain, tight deep bass, fat mids and silky top end with overall definition and brightness. Selected with balanced systems and recommended for guitar amps to improve overall response.

Peavey 'Super 7' 12AX7

9 pin miniature preamp tube (Amplification Factor = 100). The Chinese 12AX7B is very similar in tone to its standard Chinese cousin, but the Bs seem to average in at slightly lower gain and noise.

This Russian tube is full bodied and bright with a more straightforward presentation. It packs a lot of bite with its higher-than-normal gain. In overdrive, it offers a lot of crunchy fizz. High gain preamplifier tube with ultra low noise and detailed, musical tone. Unique spiral filament eliminates filament to cathode induced hum common on amplifiers that use AC on the filaments.

9 pin miniature preamp tube (Amplification Factor = 100). This Russian tube is full bodied and well balanced. It has a high gain with a very smooth presentation. In overdrive, it is not quite as defined as the 12AX7-S-JJ, but it offers more crunchy fizz.

9 pin miniature preamp tube (Amplification Factor = 100). This Russian tube has strong lows and bright highs. Its lows demand attention when playing full bar chords. In overdrive, it offers a lot of crunchy fizz.

Sovtek 12AX7WB dual triode.

Miniature high-mu twin triode each section of which as an individual cathode connection suited for use in resistance-coupled voltage amplifiers, phase inverters, multivibrators, andindustrial-control circuits where high voltage gain is desired.

Sovtek 5751 dual triode.

Miniature, high-mu, twin triode primarily designed for use in low-level stages of high-gain audio-frequency amplifiers. Use of the 7025 in this application is advantageous because of its low hum output.

The TAD 7025 WA delivers full gain with smooth top end. No microphonic issues even with the most sensitive preamps. The 7025 WA supports a fat midrange and creates a bold tone with lots of overtones. Played clean the TAD 7025 WA delivers a warm liquid tone which is very responsive to dynamic playing. Overdriven the 7025 WA provides lots of sustain with well defined mid-range punch.

A dual triode that can be used in place of most 12AX7 circuits. The rugged build of this tube and reduced gain (30% less than a 12AX7) can improve headroom and give better control in high gain stages allowing users to more easily dial in sweet spots. The JJ 5751 features a smooth and balanced tone and a detailed response with low noise and low microphonics.

A new take on the classic 12AX7 preamp tube. While it uses the same rugged build and thick glass as other JJ preamp tubes, this tube differs in construction from the typical 12AX7 in that it features a medium-long plate, which provides a dynamic and open sound with a rich forward sounding mid range. This tube offers low noise and low microphonics.

Sovtek 12AX7WC dual triode preamp tube. Made in Russia.

Tung Sol 5751 dual triode preamp tube. Made in Russia. NOS specs call the 5751 a “special 12AX7” having a high-mu amplification factor of 70.

Low-noise Tube for Best Clean Tone! The TAD Selected 5751 is Tube Amp Doctor's first choice for noticeably improved clarity, smoothness, and a true vintage tone character for most guitar amps!

Warm, clean tone with creamy overdrive! PREMIUM selected quality for the most demanding amp stages. This tube works greatly for warm clean tones and creamy overdrive. We recommend this tube for the 1st gain stage and as input tube. It upgrades 12AX7A and ECC83 tubes and replaces E83CC tubes. The HIGHGRADE Selection is the tip-of-the-top quality at the lowest noise (microphony, hum, hiss) level. Typically only 0.5-2% out of the whole production of this tube meet the HIGHGRADE requirements.

The vintage made in England Mullard ECC83 has been accurately recreated in the Tube Amp Doctor 7025 S. This highly sought after tube is regarded by many as the best dual triode to have ever been created for audio use. TAD offers a reliable and affordable way to experience the sound of this legendary tube.

The 7025 S is notable for its rich and complex harmonics. The warmth in the midrange of this tube stands out among similar preamp tubes. The TAD 7025 has nice round clean tones as well as a creamy yet articulate overdrive. Its rugged mechanical construction with extra thick mica spacers along with TAD’s premium selection process ensures a highly reliable preamp tube. Tube Amp Doctor especially recommends the 7025 S for use in British and British style amplifiers.

The Tube Amp Doctor 7025 works in any 7025, 12AX7, or ECC83 position.

Russian made reissue of the original Tungsol. The Ultimate 12AX7. Big, warm, and musical. High Gain, ultra-low microphonics, and superb linearity with a dynamic 3-D sound. Available with gold pins.

Russian made reissue of the original Tungsol. The Ultimate 12AX7. Big, warm, and musical. High Gain, ultra-low microphonics, and superb linearity with a dynamic 3-D sound. Available with gold pins.

The JJ Electronic 12AX7 / ECC83 has quickly become a modern classic in preamp tubes. Its rugged design and rich harmonics make this tube an obvious choice for musicians who need a reliable and high quality tube at a reasonable price. The balanced tone of the JJ 12AX7 works well in any amp.

The JJ Electronic 12AX7 / ECC83 has quickly become a modern classic in preamp tubes. Its rugged design and rich harmonics make this tube an obvious choice for musicians who need a reliable and high quality tube at a reasonable price. The balanced tone of the JJ 12AX7 works well in any amp.

A high performance, long plate version of the ECC83 / 12AX7. Like all JJ preamp tubes, these are built into a rugged package using the spiral filament and robust plate structure resulting in low microphonics and high reliability. The long plate version of this tube differs from the standard version with its stronger and fuller sound. This tube will work in any 12AX7 or ECC83 position.

A high performance, long plate version of the ECC83 / 12AX7. Like all JJ preamp tubes, these are built into a rugged package using the spiral filament and robust plate structure resulting in low microphonics and high reliability. The long plate version of this tube differs from the standard version with its stronger and fuller sound. This tube will work in any 12AX7 or ECC83 position.

Genalex Gold Lion ECC83/B759 (12AX7) dual triode preamp tube with gold pins. Made in Russia. Original Genalex Gold Lion ECC83/B759 tubes are considered among the best 12AX7 types ever made. They are hard to find and when they are available, they are expensive. They exhibit a large detailed soundstage that is sought after by discerning audiophiles who demand the highest quality sound. The reissue Genalex Gold Lion ECC83/B759 recreates the sound signature of the original. This tube features balanced sections and gold plated pins.

Genalex Gold Lion ECC83/B759 (12AX7) dual triode preamp tube with gold pins. Made in Russia. Original Genalex Gold Lion ECC83/B759 tubes are considered among the best 12AX7 types ever made. They are hard to find and when they are available, they are expensive. They exhibit a large detailed soundstage that is sought after by discerning audiophiles who demand the highest quality sound. The reissue Genalex Gold Lion ECC83/B759 recreates the sound signature of the original. This tube features balanced sections and gold plated pins.

$59.95 × 4
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$43.95 × 4
× 1
5AR4
5AR4
Solid State Rectifier - Yellow Jackets® YJR, For 5AR4, 5U4, 5Y3
Vacuum Tube - 5AR4, Ruby Tubes
Vacuum Tube - 5AR4, Chinese
Vacuum Tube - 5AR4 / GZ34, JJ Electronics
Vacuum Tube - 5AR4, Sovtek
Vacuum Tube - 5AR4 STR, Tube Amp Doctor
Vacuum Tube - 5AR4 / GZ34, Rectifier, Full Wave
Solid State Rectifier - For 5AR4, 5U4, 5Y3 Tubes
Vacuum Tube - GZ34 / 5AR4, Mullard Reissue
Vacuum Tube - 5AR4, Tung-Sol Reissue
Vacuum Tube - 5AR4 / GZ34 / U77, Genalex Gold Lion
Please make a selection above.

The YJR is a direct plug-in replacement adapter for use in most amplifiers that use 5AR4/GZ34, 5U4, 5Y3 or similar full-wave rectifier tubes. The YJR converts your amp's vacuum tube rectifier to a solid state rectifier, reducing tube sag for a tighter sound and feel. The tube rectifier can easily be swapped back in when sag is desired. This Yellow Jacket® is a solid state device and as such does not come with vacuum tubes.

  • Converts most audio amplifiers which use a vacuum tube rectifier 5AR4/GZ34, 5U4 or 5Y3 to a solid state device.
  • Safe for all common amplifiers and transformers.

All Yellow Jackets® have a one year warranty against manufacturer defects.

5AR4 Ruby, Rectifier Tube
Chinese 5AR4 Vacuum Tube

The JJ Electronic GZ34 / 5AR4 is rugged rectifier at a reasonable price. JJ has a reputation for building sturdy tubes and this one is no exception. Users report that the JJ GZ34 / 5AR4 is a reliable rectifier in their Vox, Fender, and hifi amplifiers.

Octal rectifier tube (Max DC output current = 250 mA)

Tube Amp Doctor 5AR4 Rectifier, Premium Selected. A faithful reproduction of the Mullard/VALVO GZ34. Pure power and the typical sag is the distinguishing characteristic of the most popular guitar amps of the 1960s guitar heroes till today.

Heater-cathode twin diode designed for full-wave rectifier operation. High output current and small size make this tube especially suitable for compact amplifier designs.

Solid State Rectifier Direct plug-in replacement for 5AR4, 5U4 and 5Y3 rectifier vacuum tubes in amplifiers with center tapped secondary power transformer. Use when less 'sag' is desired in the power supply; just switch back to the tube rectifier when 'sag' is desired.

Premium directly heated heavy duty rectifier Diode. Re-issue of the most popular rectifier valve ever built by Mullard. Helps extend the life of the other valves in the amplifier by allowing them to heat up before plate voltage is applied.

  • Low internal voltage drop & controlled heater warm up time
  • Excellent choice for both Hifi and instrument amplification
  • Replacement/upgrade for all 5AR4/GZ34 types
Tung Sol 5AR4 rectifier tube. Made in Russia. Premium directly heated heavy duty rectifier Diode. Helps extend the life of the other valves in the amplifier by allowing them to heat up before plate voltage is applied. Tung-Sol tubes reflect the best in vintage construction with unsurpassed tone and reliability.
  • Low internal voltage drop & controlled heater warm up time
  • Excellent choice for both Hifi and instrument amplification
  • Replacement/upgrade for all 5AR4/GZ34 types

Genalex Gold Lion U77 / GZ34 full-wave rectifier tube. Made in Russia.

$14.95 × 1
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$24.85 × 1
$89.95 × 1
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$34.50 × 1
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× 2
7027
7027
Vacuum Tube - 7027-A, Tetrode, Beam Power
Vacuum Tube - 7027A, JJ Electronics
Vacuum Tube - 7027A, JJ Electronics - Apex Matched Pair
Please make a selection above.
Beam power tube for high-fidelity audio-amplifier applications.

The JJ Electronic 7027A offers the same reliability and tone as the JJ 6L6GC but with the correct pinout for vintage amplifiers that use 7027 tubes like older Ampegs. At 30W, this tube delivers plenty of headroom. The highs are clear and responsive with warm mids and tight solid lows. Known for their reliability and articulation, the JJ 7027A is a great option guitar amplifiers and Hi-Fi stereo equipment.

The JJ Electronic 7027A offers the same reliability and tone as the JJ 6L6GC but with the correct pinout for vintage amplifiers that use 7027 tubes like older Ampegs. At 30W, this tube delivers plenty of headroom. The highs are clear and responsive with warm mids and tight solid lows. Known for their reliability and articulation, the JJ 7027A is a great option guitar amplifiers and Hi-Fi stereo equipment.

$68.25 × 2
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Total price for all components:
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Currently selected components:
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