(Dean Markley) Spectra 212-t schematic wanted

[crossguy]

That's the stripped down 30-T schematic. The bias circuit is the same. The cap is an 80v, and you run it down to around -42. (much like brand "F")
The finals are 6V6 though, in the 30 you can sub 6L6 with a bias adjust . Use matched pairs for best distortion.

[oshiwei]

Thanks everyone. That's a big help. It is impossible to find anything on these. I really love this amp, despite the fact that it is a beast and has four power tubes and four pre-amp tubes, making it expensive to upkeep. Definitely worth it, though.

I previously hand Fender Grove Tubes, 6L6B and 12AX7WA. But I bought some Ruby 6L6GCWSTR and 12AX7AC5 because I wanted to try something different. Thoughts?

[crossguy]

Thanks everyone. That's a big help. It is impossible to find anything on these. I really love this amp, despite the fact that it is a beast and has four power tubes and four pre-amp tubes, making it expensive to upkeep. Definitely worth it, though.

I previously hand Fender Grove Tubes, 6L6B and 12AX7WA. But I bought some Ruby 6L6GCWSTR and 12AX7AC5 because I wanted to try something different. Thoughts?

The amp was designed to sound good with generic GE UK made tubes.Different brands definitely affect the tone.
I can't recommend any brand! You'll find tubes to be remarkably fickle and inconsistent, and you may search a lot to find your tone.
It's worth it. I retube finals every two years if you're weekending, yearly if you do extended 3-4 night a week gigs. Change preamp tubes at two years or sooner if you hear tone change or microphonics. Consistent tone pays for it's self.