Tubes
Just like all other parts in the
Convertible 2000,
the tubes were selected for providing the most
musical tones. Tubes can be temperamental, but there are things that can be done to avoid
problems.
Module Preamp Tubes:
The 12AX7 tubes supplied will give you the least amount of noise and the sweetest tone.
However, they may develop a micro phonic ringing when the Overdrive control is set at 5 or
above or when using 2 or more Hi-Gain type Modules.
Typically, the input module (Position 1) is the most sensitive to micro phonics. This module is
shared by both channels.
Here are some ways to eliminate micro phonics:
1. You can swap the tube from another preamp module with the input module. (Due to
variations in internal construction, some tubes are less micro phonic than others.)
2. If you are using two identical modules and one of them is the input module, just switch
and try the other one in the first position.
For example:
Just take the two "Classic” modules and switch their positions. If the second "Classic"
module's tube does not have micro phonics, you've solved the problem.
3. Try using an FET, IC or Hot Mod module in the input. Because neither of these are tube
designs, you'll get no micro phonics. For a warmer tube sound, use an FET or Hot Mod
module in the input stage. If you're after a harder solid-state sound, use an IC module in
the input stage.
If you're involved in a touring schedule and you want to avoid tube related problems, bring
some extra tubes with you for all your equipment.
Spare Tubes
There is a spare 12AU7 tube mounted inside your
Convertible
2000. This is a stock replacement
tube for the Cascode and Classic E.Q. module.
We also discovered an interesting sound when replacing the standard 12AX7 tube in the Classic
module with a 12AU7 tube. If you use a Classic module in the input stage (Position 1), try using
the 12AU7 tube there. You'll notice a little less output volume, but it will also allow you to get a
louder, clearer rhythm. Try this setup:
If you play a guitar with a high output humbucker pickup and you're having problems with a loud,
clean rhythm, this could easily provide the sound you're after.
