Name: Steve Kennedy
Email: steve@pacair.com
Subject: overdriving
Thread: 7
Time: Sun, 27 Feb 2000 18:59:40 GMT
Overdriving a Music Man amp can be done in a variety of different ways, depending on which model or circuit topology you have.
Since all Music Man amps have a solid state preamp, the normal method of getting preamp overload (turn the input gain or volume up to dial-in the desired distortion and control the actual volume level with the Master volume control) usually results in a fairly harsh solid-state distortion that really is closer to a fuzz tone (but not as high gain) than to an "overload" sound.
On the older models (silver logo plate, pre-1980) that use a 12AX7 phase splitter and EL34 output tubes, you can crank the Master volume control wide open, then increase the input volume control until the output tubes overload and the amp will produce a very "bluesy" tone that is quite nice and mellow! I quite like the sound of output tube overload in the Music Man amps, but it is only acheived at high output levels. The amp becomes very response and "dynamic" to the touch when overloaded this way.
The newer 1980+ models (black logo plate) have a solid state phase splitter and require a bit higher drive to get the overload because you don't have that 12AX7 to help out in the overload department. In this case, all overload is in the output tubes alone.
I have used this method with a 65 watt 410-65 in a small club and it worked out great for level (with keyboards, drums, bass and a few horns).
An HD (130-150 watt) model might be too loud under these circumstances. If so, two of the 4 output tubes could be removed and/or the amp could be run in low-power mode. My 65 watt amp run in low power mode wasn't loud enough in a live situation.
If you need overload/overdrive/distortion at lower levels, but you want something more "tubey", you can simply drive the amp with a tube overdrive preamp or pedal.
I use a TubeWorks RealTube AC powered pedal that has 12AX7 tube stage in it. It has drive and output controls, as well as Low/Mid/High active tone controls. This allows you to generate the tube preamp overload sounds that your Music Man's solid-state front end cannot, while still retaining the Master volume control to give you flexibility in your playback level.
When used with an external overdrive pedal, the Music Man's solid state preamp becomes an advantage, as it is very quiet, very clean and has much more headroom that most tube preamps seem to have. This allows the amp to pass the input signal to the output stage without adding much coloration of its own, plus it can handle large input signals.
That's about all I can regurgitate on the subject... it's either "loud & proud" or use an external tube overdrive pedal. The solid state front-end of the Music Man was designed to be a high headroom CLEAN preamp, so most people find its overdrive sound to be something best avoided!
These amps won't do heavy metal or shred like a Marshall, but most other forms of overload can be induced by using the methods outlined above.
Steve