I have a 59 Bassman LTD. It is an amazing amp in all regards. And yes, it's too loud (tell me if you've heard this story before). With my LP w/ PAF's, I get a reasonably clean tone at "3" on the bright volume and from there up the amp doesn't get louder, just gloriously dirty. It's fun to get my pant legs flapping at home, but it's a bit much for the small stages I play. I have an Airbrake, but it's not good for a 2 ohm load. So I have the parts on order to install a LarMar PPIMV, to knock a few dB's off on stage. Most who have installed these seem pretty happy with them. Any down sides I need to know about?
Can't think of one. Here's my solution that keeps the amp looking stock. I use a dual pot for the volume control of both channels and put the master in the unused hole. I use a different color knob for the master.
Never installed one in a Bassman, but I have one in a JTM 45 that I'm happy with. At extreme low volumes it's a little fuzzy, but that goes away when you crack it open a bit which you should be able to do even on smaller stages.
The 2 ohm load makes this a difficult decision, IMO. The latest gen attenuators sound better than PPIMVs, especially at lower volumes, but only one that I know of (that's still available) offers a 2 ohm load setting. I'm not a Bassman guy, but if it had an 8 ohm tap, you could just re-wire your speakers to series-parallel for an 8 ohm load (i.e. (8+8)||(8+8)) and use an 8 ohm attenuator (the most readily available impedance) without mod'ing the amp itself. Another option to consider is the Clearsonic panels. Folks have reported pretty good results with those, but they obviously don't give you much control over level unless they cut enough volume for your venue to allow mic'ing it back up into the PA to the appropriate level. But, that can be a real hassle if you do mainly small-medium unmic'ed gigs.
Great idea Paul. Do you use a push/pull pot so you can control them independently, or do you just use a ganged dual pot that controls Normal and Bright simultaneously?
Yeah, from what I can tell the factory 59LTD output tranny only has a 2 ohm tap. I could change out the transformer for one with an 8 ohm tap and run the speakers series/parallel, but that's a big expensive project. The parts for the PPIMV were about $6, and it looks like I can do the mod in about an hour. I already have a plexiglas shield, it doesn't help much with overall amp volume but it definitely helps break up the beaminess of my 1x12 amps. The 4x10 Bassman actually has very good dispersion, so the shield is kinda useless.
Aaron: I just switch channels by moving my cable! You can go further and voice each channel differently. I set one channel up for Humbackers and the other for Strats. It's a few resistors and caps, so it's cheap, but best left for an experienced tech.
