Here is the layout:
SLI-80 started it
SLI-80 Sig is a standard model and they added remote control,triode/ultralinear switching while you play, all-tube headphone jack (right off the speaker taps and rocks), a 4/8 ohm switch for the speakers.
We sold for quite a while a version with Jensen Oil/Copper caps. A very popular upgrade.
I use this amp in my office and that launched the F1 version. We thought about all the upgrades we had Cary do for customers over the years, took the ones that made the real difference (hence F1....Formula 1...you only put in the stuff that makes it go fast)
So we do all of the above including Jensen Oil/Copper caps and add:
Hexfreds to the power supply for faster recovery when you are rockin' or the music gets complex.
Kimber Kable to the CD in
Grayhill selector switch....important, right in the signal path, and mondo-cool.
WBT speaker terminals.
Choice of regular or direct coupled preamp section.
Custom finishes and gold or silver leaf silkscreening.
Lastly, there is a version that has no triode/UL switch. All triode baby, and zero negative feedback. A lot of people are curious about the concept of single ended operation operation. But most of those amp have 3-15 watts of power...with a few exceptions. This will give you 40 watts and run most speakers.