IIC+ Mode

I owned the Mark V for about 2-1/2 years before trading (about 3 months ago,) and just bought another one (after massively regretting my trade.) Anyhow, I'm pretty familiar with the amp and have found that to MY EARS, running my Mark V through one of my Mark IVs power sections makes a MASSIVE difference in the depth and punch of the overall modes (mainly talking about IIC+ and IV modes here.) Now, I have never once played a IIC+, but I own quite a few Mark IV's (A and B) and am basing this on the fact that the IV's lead channel was supposed to be similar to the IIC+. In the end, I understand a lot of people's gripes about the the V's IIC+ mode, and it's lack of well...you know. Even the Mark IV mode on the V just comes to life with the Mark IV's power section. I run effects loop out of the V into the return of the IV. From doing this I have really been able to pick apart the differences in modes, as it seems they are much more complex and 3-D. Mabey I just prefer the Mark IV's power section to the Mark V's. The Mark IIC+ mode now has such an urgent and sparkley attack, with a fat punch underneath it, that it's hard for me to get out of it. Before I tried using the IV's power section, I was highly dissapointed, now I can't get out of it. As a matter of fact, the entire amp (V) is better in my opinion when running it through the IV's power section. Overall, I feel it adds some of that missing link. What are the differences between the V and IV's power section, and why is there such a huge difference in depth between the two? Has anyone else done this, and what are your findings?

It probably is possible to modify your Mark V's power section to sound more like the Mark IV's. You're going to need accurate schematics for each amp to really see what's different. Small Value changes in the power section may be all that's necessary. If you modify your amp, you will certainly void your warranty (If you still have/care about warranty).

Both amps running identical tubes? Keep in mind that MESA doesn't have a bias adjustment for the power tubes, so it may be that your Mark IV really likes the tubes it has.