When (and how often) do I need to change the tube in Le Preamp ?
This article describes when to change the vacuum tube in the Le Preamp Series preamplifiers. If you want to know how to do it, please refer to this other article.
The vacuum tube is a sturdy device, but it does wear out over time. Unlike power amp tubes, preamp tubes do not require frequent replacement or replacement as preventive maintenance. But, in order to keep Le Preamp in perfect working condition, you may need to replace the tube someday. We have taken great care in selecting a commercially available tube selected by a company renknowned for its exceptionally low failure rate (Ruby 12AX7AC5 HG) and tuned our design for what we feel is the best sonics.
Most of the time, the tube won't fail totally and suddenly. Instead, the tube will degrade gradually. Le Preamp will continue to work, but will loose gain, dynamics and harmonic richness. Eventually, the sound will become flat and lifeless.
Because of the gradual nature of this degradation, it can be hard to know exactly when the tube needs to be changed. So the general answer is : when you feel Le Preamp is not sounding or reacting to your playing as it should.
How often this should be done depends on many factors, like the original tube quality, the rate of use (the tube does not wear out if not used and stocked in good conditions), the conditions of use, and down the line, your personal taste. This makes if hard to indicate exactly how often the tube needs to be changed. The following guidelines can be given, but keep in mind that they may have to be adapted to your particular situation.
Generally speaking, a tube can give you several years of pleasure before needing a change. A hobbyist musician using Le Preamp on occasions may not even need to change it at all. On the contrary, a regular musician, using Le Preamp everyday, who whants to always keep the best tone possible, may want to change it more regularly.