From the Washington Times and VHND.com
Q: Speaking of equipment, what new EVH gear are you working on?
A: People are always screaming and yelling for that classic vintage guitar sound. The 5150 III amps are very high-gain. The main thing that we’re working on is an amp that is modeled after the old vintage Marshall that I used on the first six records. I wanted more sustain out of them.
The difference between the 5150 III amp, and this new amp we are working on is the tubes. They use EL34 tubes, which are more like my original vintage Marshall. Still trying to figure what to call it. Might call it the 5150 III-IV because they use the EL34 tubes. I told Howard Kaplan, the amp guy at Fender/EVH, what I wanted, and just last week they all came out and I gave it a test run. It blew my mind. It has the old vintage tone but with more sustain