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by Mike Beigel

Mu-FX sound modifiers by Beigel Sound Lab

presents theTru-Tron3x by Mike Beigel

designer of the original Musitronics products

Tru-Tron3x The Mu is back! Tshirt $19.95 + FREE Shipping

We will be at the LA (California) GuitarPedalExpo on March 30, 2014. Our feature item, the Mu-FX Tru-Tron 3X will be there in quantity for those who wish to try and maybe buy.


You-Tube Demos

Jerry Henderson on Instragrm

Your Language

an original bi-filter ad
BSL Envelope Controlled Filter
Historical Profile (no longer produced)

     Beigel Sound Lab was formed in 1971 and provided product prototypes of musical products. The first prototypes of a unique synthesizer and "Timbre Generation" filter bank were produced for Guild musical instruments by Mike Beigel and Isidor Straus. Then Mike Beigel set up Beigel Sound Lab to finish the production engineering and final prototypes. Shortly afterwards, Guild's president Al Dronge was killed in an airplane crash and Guild dropped the synthesizer project. We then produced a prototype envelope controlled filter from some components of the original Guild synthesizer, then formed Musitronics Corp and invented the Mu-Tron III and other products. In 1978 Musitronics was sold to ARP instruments and I re-started Beigel Sound Lab to provide musical product design services on a consulting basis.
     A prominant musician had asked for a more sophisticated version of the Mu-Tron III, so I designed the rackmount Beigel Sound Lab Envelope Controlled Filter and had about 50 manufactured in 1980. Many prominant musicians including Elliott Randall, Marlo Henderson, Tim Bogert, Michael Iceberg, Jeff Baxtor, and Will Lee used them.
     From 1996 to 2011 I worked with Mike Matthews of Electro Harmonix leading to the development of 9 products. However, we still service Beigel Sound Lab and Mu-Tron vintage equipment, and have a few selected units for sale from our in-house collection.

Mike Beigel


1979 BSL Envelope Controlled Filter


First Original Musitronics LOGO TM

Original Mu-Tron 3 From Musitronics Design
by Mike Beigel

Early Mu-Tron III advertisement. Endorsement by Stevie Wonder. 1973.