- Tubes: Reportedly 2-12AX7; 2-6AU6; 2-6BQ5
- More Likely: 2-12AX7; 1-6AU6; 2-6BQ5; 1-6CA4
- 12″ Speaker
The Lectrolab “S” series of amplifier followed the “R” series. The S400, S500, and S600 were introduced about 1965. The “S” series was a whole new look for Lectrolab. Gone was the brown/beige airline linen (irish tweed), the brushed brass burnish of the control face, and the tilted rear-facing chicken-head knobs. Now the flagship amps sported black plastic tolex-like covering, silver/chrome panels, upward-facing round knobs with metallic insets, and a metal Lectrolab logo displayed prominently across the front of the amp. And gone were the 6V6 output tubes, replaced by the EL84 equivalents of the time, 6BQ5, 7189, and 7189A.
Why change from the very cool tweed look to black tolex? Because Fender did, and no one thought tweed was cool. There was no “vintage” love back then. In 1965 kids were taking those outdated old tweed amps and spray-painting them black. The horror. I have a once-and-again blonde Bassman that went through this process. It’s a sad thing. but I digress…
A few “R” amps persisted into this era, the mid-to-late-sixties – The R700C and the R800D both began to appear in black tolex at some point. But the R400, the R500, and the R600 disappeared, replaced by the S400, S500, and S600.
And that’s the point of this dissertation – the S600 replaced the R600C. In fact, it is probable that the S600 is the same amp as the R600C, in a different cabinet. I won’t know this until someone finds a schematic for their S600, but the tubes and specs are identical. The R600C, alone among the R series, updated it’s predecessor the R600B by replacing 6V6’s with 6BQ5’s (EL84’s). It also added the 6AU6 tremolo oscillator. All of this describes the S600 also, and my guess is that Lectrolab simply ported the R600C design into the new “S” cosmetics.
Update: Thanks to Dave Kurzman, we now DO HAVE a schematic of the S600. It is almost identical to the R600C, there are a few almost inconsequential modifications. It is in the gallery below. Thanks, Dave!
Below are the only known photographs of a Lectrolab S600, the first from Jim Kachel in Minnesota. Thanks for the pics, Jim! The black combo cabinet was the original. Jim, who is an excellent woodworker, cleaned up the chassis and built a new cab for it. He put the old Lectrolab logo on the new cabinet.
The second example is the kind of sweet Lectrolab deal you can find if you’re persistent and lucky. It’s the kind of deal that makes me feel a bit guilty about describing some of the great amps made by this company, will it drive up prices? On the other hand, doing this may cause more of these amps to be appreciated and preserved.
Click to enlarge: