Ask if Mike Fortin can help. He's also in Canada.
James Peters is also a wizard with amps, although I'm not sure if he does mods these days, or just builds his own creations
Part of the CCV's sound is high plate voltage, which I'm not sure the JVM could match. You also have to specify which settings you're referring to with the CCV, as in my experience, the mode switches on the CCV can dramatically change its tone.
i'm refferrring to a video that is no more on Youtube from Mark Day when he couldn't bring is guitar cause Air Canada BLaBlaBla… but you can hear the ROAR in that video too: https://www.youtube.com/watch?v=PzGSUZiG_vI
Part of the CCV's sound is high plate voltage, which I'm not sure the JVM could match. You also have to specify which settings you're referring to with the CCV, as in my experience, the mode switches on the CCV can dramatically change its tone.
I have a Marshall 1987x with a CCV/Ocean/Custom 75 Modification done by Mark. The CCV is CCV-ish, but certainly not 100% of what you get from a real CCV.
Just get a tone that you like and use it. There are so many variables beyond just the amp that you're hearing when you listen to a video clip. For all the effort that players put into chasing tones, most of the time they'd be better off just dialing in what they have and playing more.
One inch difference of mic placement will likely have a bigger effect on your tone than switching from a JVM210 to a CCV (all other things equal)...don't get lost in the minutia.
Part of the CCV's sound is high plate voltage, which I'm not sure the JVM could match. You also have to specify which settings you're referring to with the CCV, as in my experience, the mode switches on the CCV can dramatically change its tone.
Regarding the preamp, there are numerous changes to the standard Marshall preamp topology, and the addition of diode clipping before the tonestack. The gain control has also been moved to just before the tonestack. Doing that with a PCB tends to require some rather ugly circuit board surgery.