I played around with the Throttlebox and my Mark V this morning in a couple of different configurations.
1. I used the Mark's graphic eq everywhere and kept the tone and mid cut knobs on the Throttlebox turned all the way down.
2. I put my OD-808 in front of the Throttlebox
3. I tried the Throttlebox on the Mark's clean channel. Outstanding.
4. I switched to Channel 3, turned the gain pretty much all the way down on the Channel 3, and switch to 90 Watts, Pentode, Extreme Mode (like modern mode on the recto, this removes the negative feedback control from the power section): sweet baby jesus.
5. I also played with full and variac power.
Ladies and gentlemen, we have a winner.
I am not going to bother trying to A/B this with an actual recto because that will just result in more tail chasing. But to my (rather dubious) ears, this sounds phenomenally good.
Good enough that I may not buy my recto back after all.
-D