Saturday, August 2, 2008

Ol' Smoky--Revisited

I decided to jump in and try a simple mod that my amp guru Stephen Schneider suggested that may just put my Ol' Smoky amplifier more into the harp tone zone. Since I had the amp unbuttoned, I also decided to depict the guts for all to see in the photo above. For those that haven't read the previous Ol' Smoky post, the official name for the amp is a Bell 3725 built by Bell Sound Systems many decades ago. I related in the post that it had a decent sound for amplified harp, but was a bit cleaner sounding that my main squeeze--the Silvertone 1483. If you look closely at the photo, you'll see a bunch of new capacitors, resistors and wiring that replaced those that were toasted from a pre-owned chassis fire. What Stephen suggested was to unhook a lead from one of the pre-amp cathode bypass capacitors and try it and then unhook the other other one and see how it sounded. The capacitors are the small black 50mfd/50vdc Sprague Atoms in the upper left hand corner of the photo.

Pulling the first cap from the 6SF5 tube made a slight difference played through my JT30 crystal mic and the Python 4x10 cab (posted about earlier), but it wasn't significant. The tone improvement took place after snipping the capacitor shared with the 6N7 tube. Ol' Smoky bloomed into an amp that exhibited better compression than before and had a bit of a crunch that wasn't happening prior to this modification. The bottom end tonal range had more thump to it and was getting mighty close to what I liked about the 1483. I A/B'd the two amps and the 1483 still has it beat, but the differences are way more marginal now. I now have a couple of 2-6L6 amplifiers that can do-the-do. Hats off again to S.S.

Stephen tells me that he is now following his own advice with his 3725B models, but with some additional mad science experiments. He has the advantage of being able to jump out into a live stage gig scenario, that proves the pudding much better than me rattling around at the house. He'll get back to me on those. IF I try some of those, I'll get back here and report the results. Right now, the Ol' Smoky's got it going on much more better. Anyway--

No comments: