Does anyone recognize this mod?

I've got a MM Sixty Five Reverb head. It has a mod on the dry channel that appears to be a phasor of some sort. It will become a moot point for me, as I have put the amp up on ebay, but I'm still curious if anyone else has seen this mod, and I also thought it might be helpful for someone else if they've got the same thing.
I'm not sure how to post pics here, but the ebay sale is here - \newurl
{http://cgi.ebay.com/ws/eBayISAPI.dll?Vie wItem&ih=016&sspagename=STRK%3AMESE%3AIT &viewitem=&item=260052406168&rd=1&rd=1,h ttp://cgi.ebay.com/ws/eBayISAPI.dll?View Item&ih=016&sspagename=STRK%3AMESE%3AIT& viewitem=&item=260052406168&rd=1&rd=1}
Has anyone seen this before?
Thanks,
Jeff LaGrange

Interesting... the circuit board is big enough that if it was from a pedal it was a larger one. It might have been homemade or it could have been a "kit" from somewhere. I certainly don't recognize the board.
It looks like the installation workmanship is pretty good. Perhaps it will be another unsolved MM Mod Mystery?
When I bought my HD130 head on eBay, I found that it sounded TERRIBLE... no headroom and early ugly distortion. I thought something had failed! When I opened it up I found that someone had modified the preamp for more gain, trying to get distortion out of it. Instead, it was oscillating and causing all sorts of sonic havoc. You couldn't get a decent tone out of it at all... clean OR distorted.
I removed about 5 or 6 parts and restored the circuit to the schematic and it sounded great!
Steve