Guys - on the Master Volume and pushing the power section.
Per Santiago, cranking the Master volume will not push the power section any harder. He actually recommends pushing the channel volumes higher as opposed to the Masters.
This link is probably the end all be all for JVM and Marshall fans if you want to know from Santiago.
Click Here.
In my opinion as a JVM 410H fanboy, Marshall needs to update the amp.
1. get rid of the serial/parallel loop and add a basic serial loop ala HJS.
2. Dump the reverb, nobody uses it and make the Noise Gate standard ala HJS.
3. Revoice the Crunch channel to be even more JCM 800, it's a little boomy by itself IMO.
4. Line out / IR. Do something here, I know Marshall is planning to go that route in some way, the JVM needs to be updated with that tech.
5. Possible optional upgrade, add a choke. IMO it doesn't make a difference, my modded JVM had a choke and I just didn't notice a difference but for some players, that seems to be a hangup.
Basically what Satriani did was update things like the loop, the gates etc... which I think Marshall needs to incorporate. The problem with me and the HJS is they tamed the amp down by revoicing certain channels and dialing the gain back, it's a dull amp IMO. I liked the logical updates but hated the revoicing of the HJS.