This is the modern version, pcb build, all tube audio path, solid state rectifier, We have one, just recapped the power supply in early 2021, sounds great! Its a cathode biased 1 x 12" using 12AX7's in the pre and verb sections and 4 EL84 for power. It has a switch for moving the tone stack (H, M, and L) either before (classic Fender amps, such as the Princeton and Twin Reverb), or after (like non-MV Marshalls, such as the JTM45 and the Plexi) the first gain stage. This amp sounds great just dialed in on its own, maybe does not have as much clean head room as heavy pedal board players want, although it does play clean at decent volume. Depends if you like the sound of your guitar or of your pedals better I guess...