SarnoMusicSolutions wrote:I talked to Ron Wickersham about this because we modded a friends EB3 with the Hammon Dark Star pickup. We never did the active electronics, but I did learn a bit about it from him. The buffers were definitely NOT like the Blaster. The Blaster, technically speaking, really isn't a buffer. It's more of a booster, preamp since it's set up as a gain stage with a high-z output.
A true buffer suggest that it's unity gain and has a low Z output. On Phil's bass, Ron had hooked up each pickup with its own buffer. He used a (now ancient and archaic) RCA transistor device that internally was set up as a "Darlington Pair". This made it a great buffer, with gobs of ability to drive all kinds of cable length and "crap" without suffering tone loss. But those old devices are noisy and unstable compared to more modern parts. If you want a much higher performance transistor to do this identical job, look for the more modern and readily available MPS-A18 transistor. This is a very high gain, low-noise, Darlington pair type transistor. When used as an "emitter follower" buffer, all that gain translates into unity gain with all kinds of current drive ability. Just look up "emitter followers" and it should be cake to accomplish. All you'll need is a couple of cap's, the MPS-A18, and a resistor and 9 volts. That's per pickup.
As far as tone controls and filtering, I can't help you there, but maybe Fred Hammon could.
I'm back on this project and am very slowly coming to understand what you're telling me. I read up on Darlington Pairs and I think I get it, but please correct me if any of this is wrong. It's two transistors used as amplifiers where one amplifies the signal and the second amplifies the output of the first one even further. The MPS-A18 is a single unit that accomplishes both tasks.
Emitter Followers are still over my head... I haven't found an article yet that breaks it down to my level or better yet some directions that say "buy these parts and solder them together this way"... but at least I'm making progress.
What I need to know right now is: I'm finally at the stage of ordering the Dark Star pickups. Fred mentions on his FAQ page to look for Low Impedance models in the future: http://www.hammoneng.com/faq1.htm Should I ask him if he'll make me a prototype set (he hand-winds all his pickups so it should be easy, I think) or just get his regular high-impedance pickups?