Balanced triodes. Gimmick, or worth the money?



Asked by: Stacie Robinson

What is balanced triodes in tubes?





What do balanced triodes mean? Do I need them? Dual triode preamp tubes like the 12AX7 really have two separate tubes inside one glass envelope. When the plate current draw of each triode is the same(as evaluated by our VTV testers), we refer to that as having balanced triodes.

How important are matched tubes?

Power tubes are electrically matched so each tube will have the same amount of “idle” plate current and amplification characteristics when used in an amplifier. This is done so the tubes can work together in your amp giving you optimal sound quality and tube longevity.

Do tube amps actually sound better?

Just like our ears, musical instruments and just about everything else natural, tube amplifiers have the least distortion at the lowest levels. This is why a tube amplifier can sound great played softly, while with transistor amplifiers people are usually needing to turn it up to have it sound best.

Why do tube amps cost so much?

Tube amps are expensive because they adopt pre and power tubes as their primary amplification source. Each tube costs roughly $50 and can have up to 4 of them within a single unit. Secondly, these amps have more expensive components, larger cases, and more complex circuitry than solid-state amps.

Do preamp tubes need to be balanced?





the term “balanced” is refering to your last pre-amp tube, before you get to the Power tubes. You’ll want this to be balanced. You just need one. If the other pre-amp tubes are balanced as well, that’s fine but they don’t need to be.

Do preamp tubes need to be matched?

Preamp tubes are, in the majority of cases, self-biasing. Therefore, they do not require matching. Only tubes that are in a push/pull Class AB circuit need to be matched because they share a common bias voltage.

Do all 4 power tubes need to be matched?

Power tubes require matching because the way they amplify signal can create exceptionally bad sound if they are poorly matched, but pre-amp tubes generally aren’t used this way and so matching them is unnecessary.

Do matched tubes need to be biased?

Due to the wide variance in tubes (even of they same type and brand), tubes therefore need to have the bias adjusted every time you change them. Yes, every time.

Do you need to bias matched power tubes?

Conclusion: You’ll need to bias most tube amps if you change the tubes. This is because you cannot buy tubes with a similarly matched resistance. You should always buy a matched pair or a matched quad of tubes, but the chances of them matching your current pair are very small.



Are tube amps really better than solid-state?

Answer: Tube amps are generally better than solid-state amps in terms of sound quality, but solid-state amps are usually cheaper and more sturdy than tube amps.

Is it okay to leave a tube amp on?

Long story short, unless you plan on using your amp a lot throughout the day, you should turn off your tube amp when you are done using it. Here’s why: Tubes deteriorate with use, so leaving a tube amp on shortens tube life. Many tubes produce a significant amount of heat.

Why solid-state amps are better?

1. Solid-state amps are great for players who want maximum headroom (a.k.a a loud, clean, undistorted signal). But without a bit of natural distortion, an electric guitar can sound a bit brittle. As such, solid-state amps are more popular with bassist and keyboard players than with guitarists.



How often should you change your preamp tubes?

You are not likely to have to replace them unless one or more tubes fail. Preamp tubes can have a life span of at least two to three years and usually much longer. If it’s been a few years or you regularly change your power tubes and feel like the amp has become lifeless, it may be time to freshen up your preamp tubes.

How long do preamp tubes last?

2 – 3 years

Preamp Tubes are generally at their best 2 – 3 years. Power Tubes are generally at their best 1 – 1.5 years. Rectifier Tubes are generally at their best 3 – 5+ years.

Can I mix and match preamp tubes?

It is perfectly okay to mix preamp tubes. In fact, it might be recommended in some cases. The reason why some musicians mix and match preamp tubes is because using different tubes can change or improve the tone of your preamp or amp.



Can I use a 12AU7 in place of an 12AX7?

While you can physically use a 12AU7 tube in place of a 12AX7 in a circuit, it’s not recommended to do. Most circuits that are designed for a 12AX7 will not react well to the significantly lower gain of the 12AU7.

Do preamp tubes affect tone?

More to the point here, though, is the fact that the gain of the first preamp tube—often referred to as a “gain stage”—very directly impacts the tone that you achieve from the amp as a whole.

Can you mix 12AX7?

You should be able to swap preamp tubes of the same type without problem. For example, any 12AX7 should be compatible with another 12AX7. With power tubes, you can swap different brands of the same tube.

What tubes can replace 12AX7?

Knowledge is power, and knowing an unusual substitute may be a true joy.



  • Small Signal Tubes:
  • 12AX7. Substitutes: ECC83, 12AX7A, 12AX7WA, 7025, 5761,6057,6681,7494,7729, 7025#, ECC83#, 6L13, 12DF7, 12DT7, 5751, 7025A, B339, B759, CV4004, E83CC, ECC803, M8137. …
  • 12AU7. …
  • 12AT7. …
  • 6DJ8. …
  • Rectifier Tube:
  • 5AR4. …
  • Other Dual Triode Tubes:

Can I replace 12AX7 with 12AY7?

You can interchange a 12AX7 with 12AT7, 12AU7, 12AY7 or 5751 as they are all the same pin structure, however they will each give you a different result in your amp. Each of these tubes has a different gain factor, which means some will give higher gain and others lower gain.