I thought I had posted this already. If I did, sorry for the repeat. I did update the image today so here it is. This amp is very close to the RA100 except for the op-amp circuits that follow the Hi and Lo gain channels, those are not present on the RA100 Hi/Lo gain circuitry but the buffers after the clean channel are there. If you ever wondered where the highest gain of any amp came from, it is due to the op-amp circuits that follow the tone stack. the op-amp compensated signal path does prevent you from gaining any changes with tube swaps for V3 and V4. You may notice a slight change but not much. V5 and V7 are the two positions you can get some change. The JAN/Phillips 12AT7 in V5 on the TC100 did make a world of difference. V7, use any 12AX7 you want. Regardless of the design, the TC100 and TC50 are decent amps.
