Mike Beigel, inventor of the holy grail Mutron III envelope filter, amongst other pedals, has passed.

May the Four Winds Blow You Safely Home.

Bill, tgo

A massive loss!

Peter

That is a bummer; very sorry to hear.  Such a cool run of innovative (and stylish) effects, back when Musitronics/Mu-Tron was in their heyday.  I feel extremely lucky to own an original Mu-Tron III; it's one of my most treasured possessions.

I don't know anything about Mike Beigel on a personal level, but that's a loss to the audio world for sure. 

Quote from: flavofive on September 23, 2026, 11:26:22 AMI feel extremely lucky to own an original Mu-Tron III; it's one of my most treasured possessions.

I'm thinking there are at least 2 of here who are quite envious!

Peter

I had an original Mu-Tron III for decades.  15-20 years ago, I sent it to Mike for a tune-up and mod for true bypass.  He was great to deal with.  I sold it a couple of years ago for around $800.  I loved how it sounded, but it was so big it had its own zip code.  I now have a mini $35 Donner that gets me 80% there, which is all I really need.

I've read a lot of good reviews of the newish Behringer envelope.   Still bigger than a standard Boss pedal.

Bill, tgo