Can’t find the best 12AU7 tube? We’ll help you find a good option for your amplifier.
A medium-gain dual/single triode with the lowest gain factor amongst all commonly used preamplifier tubes, the 12AU7 has several names for identical variants. 12AU7 is used for this lowest medium-gain preamp tube in the US with its European variant known as ECC82. The 12AU7 continues to be a preamp vacuum tube available in a wide range of options in the market.
While the different variations of the 12AU7 preamp vacuum tube go into the same electrical plug, technically speaking still perform better compared to their counterparts when used individually.
Though the 12AU7 is less extensively used than the 12AX7 or 12AT7 owing to its low gain, the former finds widespread application in numerous hi-fidelity recording and audio systems because they provide more headroom. In addition, different 12AU7 versions or variants are designed for serving specific purposes or purposes such as long-term use, low noise, and reduced microphonics.
Without further ado, let’s take a look at our list of the best 12au7 reviews:
Best 12AU7 Tubes – 12AU7 Tube Comparison
1. JJ Electronics 12AU7/ECC 82 Preamp Vacuum Tube (Editor’s Choice)
The JJ Electronics 12AU7 preamp vacuum tube is the North American counterpart of the versatile European ECC 82 preamp tube. Designed along the same lines as the iconic 12AX 7 JJ vacuum tube, the JJ 12AU7 is one of the most heavy-duty tubes you’ll come across. However, putting things in perspective, this 12AU7/ECC82 tube from JJ is a medium-gain dual-triode crafted with meticulous care for durability.
The JJ 12AU7 comprises two individual triodes set in a single vacuum tube. And like most other electronic equipment, this preamp tube is compatible with users across various applications, including RF and audio circuitries. You’ll find this 12AU7 in guitar amps and several Hi-fi accessories as it helps deliver flat, full, and smooth tunes. Speaking this preamp tube lets you elevate the gain minus the hiss and distortion.
Any listing of the top 12AU7 tubes will inevitably contain the JJ 12AU7/ECC preamp vacuum tube, thank to its versatility. These 12AU7s are not hardy and performance-driven but supremely affordable at the same time and, of course, sound decent enough. If you’re expecting fine, well-balanced bass typified by profundity together with highly detailed highs and smooth mids, then look no further.
This JJ 12AU7 compares favorably to other similar 12AU7 tubes such as Mullard or Electro-Harmonix with its warm, dynamic response. Given the JJ 12AU7 preamp vacuum tube’s fantastic durability and resilience, as well as the tube’s high quality, it’s moderately priced.
Features
- Medium-gain dual-triode preamp tube
- Gold-pin variant also available
- Keeps tone pristine and smooth
- Overdrive is controllable as it comes on more slowly and gradually compared to an OEM 12AX7.
2. Electro-Harmonix 12AU7 EH Vacuum Tube (Close Runner-Up)
If you want your guitar amp to perform beyond your expectations, then you don’t need to look beyond Electro-Harmonix 12AU7. This top-quality 12AU7 EH vacuum tube from Electro-Harmonix carries on the legacy of vintage tone, analog sound, and soulful harmonics. In addition, the EH 12AU7 vacuum tube comes across as an advanced medium-Mu twin triode ideal for using in speaker driver- and preamps circuitries.
This premium 12AU7 EH vacuum tube also works as an ideal and standardized replacement for all 12AU7/ECC82 circuit types. You can rest assured that if you opt for this 12AU7, it’ll go a long way in making your guitar driver or amp sound exceptional. With this EH 12AU7 installed inside your bass amp or sound system, you can take it for granted that reproduced tones will sound amazing across the entire frequency spectrum.
You bet this 12AU7 EH preamp tube will perform as effectively as any other similar vacuum tube in the market. Other things remaining the same, perhaps the only trade-off you’ll have to settle for is a slight reduction in detail. As long as your audio setup is decent, you can expect great results from this versatile Electro-Harmonix 12AU7 tube.
Features
- 12AU7A/ECC82 Electro-Harmonix vacuum tube
- Better-quality medium-Mu twin triode
- Drop-in replacement for any stock 12AU7/ECC82 vacuum tube
- High linearity
- Low microphonics
- Russian-made
- Analog sound typified by poignancy and warmth
3. Genalex Gold Lion 12AU7 Tube
The Genalex Gold Lion 12AU7 Tube tends to be one of the most exclusive 12AU7 vacuum tube types inspired by the original Genalex Gold Lion ECC82/B749 preamp tube. This 12AU7 vacuum tube by Genalex is highly sought-after by audiophiles and music enthusiasts owing to its extraordinarily low distortion, well-balanced sound, and outstanding linearity.
This Russian-made reissue Genalex Gold Lion 12AU7 equipped with electroplated gold pins has been engineered with meticulous care for replicating the original tube’s features.
The Gold Lion 12AU7 Tube serves as a drop-in replacement for any standard 6189, 5814, ECC82, and 12AU7 vacuum tube. By and large, this Genalex 12AU7 tube with gold-plated pins offers a superior soundstage than most other similarly priced tubes. In addition, many audiophiles and musicians have substantiated that the Genalex Gold Lion 12AU7 sounds much better than Mullard or EH 12AU7s.
This 12AU7 vacuum tube excels when it comes to reproducing the midrange frequencies, and you’ll indeed feel the thrilling mids effects. The 12AU7 is a dual triode preamp tube manufactured in Russia guaranteed to sound excellent from the start, even before burn-in. So you can take it for granted that your amp will give off tauter bass, airier mids, cooler highs, and detailed treble with sparkling transparency.
Features
- Genalex Gold Lion single-triode 12AU7 preamp tube
- Russian made
- Low-noise and well-balanced sounds
- Low-gain triode
- The extremely taut base for enabling mids to come through perfectly well
- Smooth and clean sound with ample detail and power
4. Mullard 12AU7 Preamp Vacuum Tube
The 12AU7 Preamp Vacuum Tube by Mullard is one of the most performance-driven ECC82/12AU7 reissue vacuum tubes, thanks to its minimal microphones and low noise. So in case you’re looking for a hardwearing and quality 12AU7 for your hi-fi amp, microphone, or reinforced sound system, you can never go wrong with the Mullard 12AU7. This Russian-made preamp vacuum tube packs a punch despite its small size rendering this tube perfect for low-gain 12AU7 applications.
At the same time, this Mullard 12AU7 works seamlessly with any standard Hi-Fi system, including but not limited to preamps. Many music lovers and enthusiasts have substantiated that the Mullard preamp tube 12AU7 tends to be a noticeable and obvious upgrade over the JJs 12AU7. Enough this 12AU7 from Mullard provides you with a warmer, richer, and clearer tone.
Generally speaking, the Mullard 12AU7 preamp vacuum tube is ideal for producing excellent mid and low-range acoustics. Often the higher-end range is somewhat subtle but, on the whole, conveys a detailed, rich, and warm sound. Not least of all, this 12AU7 has a distinct edge over other comparable 12AU7s in flattening out the frothiness of bass amps.
Features
- Preamp vacuum tube, single-triode
- Low-gain tube guarantees low microphony and hence minimal din
- Provides superior headroom, i.e., signal-handling capability compared to 12AX7
- Crystal-clear reproduction when installed in a hi-fi guitar amp
5. Tung-Sol 12AU7 Preamp Vacuum Tube
Modeled on an incredibly durable military-grade vacuum tube, the all-new reissue Tung-Sol 12AU7 comes with superior features for offering extraordinary audio output. Since it is a military-grade preamp tube, it can hold its own and remain intact even during a catastrophic nuclear explosion. It is a quality medium-Mu twin triode supremely compatible for setting up inside speaker driver and preamp circuits.
On the other hand, this Tung-Sol 12AU7 vacuum tube works as a premium replacement for all and any 12AU7/ECC 82 circuit type. The counterpart to the European ECC82 preamp tube, the Tung-Sol 12AU7, can be utilized in any ECC82 or 12AU7 circuit. Famed for their consummate acoustics, Tung-Sol tubes are made by adhering to rigorous quality control standards and are committed to quality manufacturing.
Features
- Preamp vacuum tube single-triode
- Russian-made
- Equivalent to ECC82
- Highest linearity
- Ultra-low microphonics
- Factory preset for consistent performance and greatest tolerance
6. JJ 12 AU7 /ECC82 Gold Pin Vacuum Tube
The 12AU7/ECC Gold Pin Vacuum Tube from JJ Electronics is a performance-driven medium-gain dual-triode delivering smooth and crystal-clear tones. No wonder you’ll discover this premium JJ 12AU7 vacuum tube with gold-plated pins in guitar amps and drivers as well as hi-fi equipment. This gold pin preamp tube, an extended plate variant of the original 12AU7/ECC82, is sturdily built, featuring a hardy package with a solid plate and spiral filament.
Consequently, the gold-pin ECC82/12AU7 tube reproduces balanced acoustics across the entire frequency response scale with dynamic sound and low microphones. Additionally, the extensive plate coupled with the hum-canceling spirally wounded filament imparts to this tube extra drive so essential for extremely demanding auditory experiences. As a result, this JJ 12AU7 gold-pin tube effortlessly spans all realms regardless of whether it entails caressed audiophile listening or the severity of musical instruments’ notes reproduction.
Features
- Gold-pin preamplifier vacuum tube
- Medium-gain dual triode
- An ideal choice for a guitar amp, studio-, and hi-fi- sound systems
- Spiral-wounded filament
- Extensive plate version of the standard JJ 12AU7
- Full-bodied acoustics with a wider and balanced frequency response
- Encompasses a gamut of harmonically vibrant mids with immaculate highs and profound lows
FAQ: the Best Sounding 12AU7 Tubes
Can I Use 12AX7 Instead of 12AU7?
If you look closely under the hood of a guitar preamplifier, you’ll most likely see anywhere from 1-6 preamp tubes. Whether a specific bass amp will have 2, 4, or 6 preamp vacuum tubes largely depends upon the equipment’s design. However, you’ll usually find a 12AX7 and often come across a blend of 5751, 12AY7, 12AU7, and 12AT7. Since these preamp tube types have nearly identical pin layouts, you can use them interchangeably for your preferred acoustic reproduction.
So can you use 12AX7 instead of 12AU7? Before we can answer this question for you, let us compare the 12AU7 with the 12AX7 head-to-head.
12AU7 Tube
Of all the tubes you’ll find in the market, the 12AU7 has the lowest amplification factor (20) hence the lowest gain (approximately 17). Owing to its extremely low-gain factor, the 12AU7 finds more extensive application as a driver for the Micro Tube Spring Reverb (a transformerless standalone unit for heightening spacious boom to line-level signals) and less as a bass preamp. However, the 12AU7 is frequently used in the guitar amp’s phase inverter position owing to its excellent acoustic fidelity.
12AX7 Tube
So comparing and contrasting both the tubes, you may observe that the gain factor is inversely proportional to the current. In other words, if the electrical current supplied increases, the gain decreases, leading to enhanced headroom and better acoustical fidelity. Low-gain tubes also reproduce the entire spectrum of the frequency range more balanced manner with reduced microphonics.
If you’re looking for a cleaner and smoother bass tone with extra headroom (and you’re willing to trade-off for a drop in volume), then you can replace a 12AX7 with 12AT7. In this case, the 12AU7 doesn’t make a suitable replacement for 12AX7 due to mismatching or bias leading to the tube performing erratically. Before you can swap a 12AU7 with a 12AX7, you’ll need to inspect your guitar’s wiring for the appropriate resistance load required to use a 12AX7.
Bear in mind that there’ll be a volume escalation with a considerable spike in gain when you use a 12AX7 in place of 12AU7.
How Long Do 12AU7 Tubes Last?
12AU7, 12AX7, and 12AT7 typically tend to be small-sized signal tubes with a functional lifespan ranging from 5,000 to 10,000 hours. Thus, these preamp vacuum tubes usually take about 100 hours to break in before they attain peak performance levels.
Conclusion: The Best 12AU7 Tube Is…
This review closely looked at some of the top-notch 12AU7 preamp tubes from JJ Electronics, Electro-Harmonix, Genelax, Mullard, and Tung-Sol. Performance-wise almost all the brands are comparable to each other. However, a few stand out, e.g., the Electro-Harmonix or the Genalex. Since all these 12AU7 are pocket-friendly, you can experiment with them to find your best fit.
Overall, the JJ Electronics 12AU7 is the best tube for audio, in our opinion.