Hi GG,
I have played with this a far bit.
I have found the following.
1. Keep the master Volume on 5 or Below.
2. Turn up the Volume Knob to at least 5. Which is 12 O 'clock.
I have found having the Volume Knob on 3, I had to crank my amp louder to get the volume. This sort of over drives it.
I tried the Triaxis Volume on 5, the cleans sound much better, not a Fender clean, but hey it's Mesa, right
Also be careful of the Dymanic Voice, if you are using that it also can add distortion. keep it on 5 or below.
It has taken me 2 months of tweaking to find my sounds, I'm almost there.
Also there is talk around here about Changing the Tubes to a lower gain tube.
12AX7 = 100 Gain
5751 = 70 gain
12AT7 = 60 Gain
Now I have changed my tubes about 50 times, I have settled on the following.
V1:EH - 12AX7
V2
hilips - 12AX7 Old Stock.
V3:Jan - Philips 5751 NOS.
V4:EI - 12AX7
V5:Mesa - 12AX7 Russian 2.
I tried a lot and many sounded great at low volumes but at high volumes, it becomes very difficult to tell them apart.
I believe that the 5751 gives you slightly better Bass than the 12AT7, but that's my opinion only.
Hope that helps,
Gezza.