Some of you may have read my review of the Lindy Fralin Thunderbird bassbuckers from RS Guitars that I installed in my Epi Les Paul Standard. While I said I liked them, they sounded very little like old an TBird, which is supposedly their progenitor tone. I recently discovered that my initial impression may not necessarily be the whole story.
I have a huge amp stable, and I periodically rotate them around just to keep my ears sharp and their caps in shape. The amp I am using now is my Trace Elliot VA350, a very rare precursor to their chrome tube "Hexavalve." One of its features is a mostly useless, very high gain, high impedance tube instrument input completely separate from the onboard s/s GP11 preamp. Even though it has its own separate master volume, it's normally just too gainy for anything and produces a nasty distortion with even the most mild-mannered passive bass.
Just for grins when I was playing around at home, I decided to give my Epi a try through the Trace. Going through the regular preamp produced pretty much the same tone that I get with my other basses, albeit at a lower voume since, as I have noted before, the Fralins have a pretty low output. Since their output is so low, I decided to run the bass through the aforementioned tube input and lo and behold, my Les Paul not only didn't overdrive the input, it sounded EXACTLY like a vintage Thunderbird: snarl, bottom and all those gloriousy pissed-off mids that somehow never turn nasal.
I guess that when those pickups were designed, they were tested on a high-gain guitar-style tube preamp which would be similar to the amps T-Birds fed back in the day, not taking into account that modern bass preamps are lower in input impedance to sound slightly "scooped" and be able to deal with active preamp circuits. Even the original SVT has a variation on this idea with a drive stage that sacrifices voltage gain for higher current thump. When the Fralin pickups mate to a circuit like that, they have a low output, almost polite tone, but when fed into a high impedance, high gain tube pre, they show their colors. Needless to say, that's a very cool discovery for me.
