Short Backstory: I have a Sunn Concert Lead Red Knob from 1976. I've had it since the 90s, Acquired from my quitar teacher who got it from who knows where. It did not come with the Footswitch. Off and on with long periods of disuse I've been looking for this mythical 7 pin blue connector footswitch of unknown dimensions. I've studied the Lead Schematics, Read through endless posts about things that sound close but not quite. Come across more than a few people sharing my plight. I made a marvelous discovery...in my various searches for this connector I FOUND IT!!!
http://www.amazon.com/COOPER-INTERCONNECT-126-195-CIRCULAR-CONNECTOR/dp/B00DDE6MD4/ref=sr_1_1?ie=UTF8&qid=1464222331&sr=8-1&keywords=cooper+126-195It is a modular plug so you can buy all of its parts individually as well.
As you can imagine this was a eureka moment. But it gets better. So I'm obviously on Amazon searching for parts. I do a random search for "SUNN" and get all sorts of albums and tubes and stuff. And a posting for a Sunn Concert Lead 7 pin Footswitch. Used...and the connector is missing a pin. Can you BELIEVE that...on AMAZON!!!
http://www.amazon.com/SUNN-footswitch-concert-lead-amp/dp/B01D7JBZAE?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00Of course I ordered it on the spot. And Just the tip of the modular plug also on Amazon. This is amazing. I just got them.. Replaced the plug tip and guess what...IT WORKS!!! The distortion switch turns on the distortion...the boost gives a boost...and the reverb turns on/off the reverb.
now here's to the mostely part.
I've used this thing off and on quite a bit over the years. The distortion has worked with the switch on the face and the knob did its job of dialing in the distortion. Its always done this thing where when the distortion switch is flipped the distort knob works fine...but if the distort switch is off the knob seems to act like a tone knob and it sucks all of the highs to mids out. Never been a problem without a footswitch...I'd just flip the switch and turn down the knob to play clean. Now that I have the footswitch that will not work.
Any Suggestions would be welcome