Music Man HD Preamp

[HamishR]

I had a Music Man amp for a while back in the day. I think it was an RD-12 - something like that. So when I found a schematic for a Music Man preamp I felt I should try it to see if I could remember how it sounded. I built one from what I now realise was a slightly inaccurate schematic. So this is a schematic from a correct schematic - or at least one which will work. The main issues were in the tonestack where the pin numbering for the Bass and Mid pots were backwards.

Anyway I'm pretty pleased with this layout. It's as compact as I could get it. I don't mind standing resistors as long as they're few. I believe that they are considered potentially unreliable for use in an aerospace context, but the only flying my pedals are likely to do is if they displease me. I am a hard taskmaster...

 

[HamishR]

Now that I've had a chance to play this a bit (with a Gibson ES-330 through a Marshall plexi style combo) I really like it. It's a really cool sound. With Gain on full it's a pleasant enough dirty sound but I find that I'm really liking it with Gain at around noon - 1.00. It does the "edge of breakup" thing really well, with a full, clear sound. It's not buzzy or fuzzy; it's chunky and clear with very musical mids. Maxing the Gain is still usable and may be perfect in the right context but for me the sweet spot is in the only-just-dirty spot. The low end stays tight and clear which is something I particularly love. There is plenty of volume on tap too. I had to check I hadn't used a linear pot for Volume.

The EQ can get a bit funky at extremes! It's a bit interactive in the bass and mids area and can sound a bit weird and scooped at some settings. But keep all three knobs around noonish and it's hard to go wrong. It's better than most overdrives IMO.