Mu-FX (by Mike Beigel) Tru-Tron 3X



Mike Beigel about the prototype

The unit, although smaller than its predecessor, the Musitronics Corp Mu-Tron III, is BIGGER in features and EQUAL OR BETTER (my opinion) IN SOUND AND VERSATILITY.

When the unit is set in "MU" mode, it works as exactly the same (and to my ears sounds exactly the same) as the Mu-Tron III vintage unit--I have tested it against 2 Mu-Tron III units AND some of the other envelope filter products I designed.

HOWEVER, the Q CONTROL dial goes to 11 and for a good reason!

I have added a significant amount MORE Q to the filter. So to get Mu-Tron III Q, you just need to turn the dial back a little from what you would usually use to get the same Q as on a Vintage Mu III.

The MU DIAL (top left control) controls the signal gain to both the filter audio and the envelope generator, as in the Vintage M-III

The FILTER MODE switch now has 4 positons instead of 3. The 4th position, "MIX" is a carefully mixed blend of the original signal and the LOWPASS MODE from the filter. It's the best mix sound I could get from all the possibilities I tried.

There are also TWO OVERLOAD INDICATOR LEDs to help you dial in the sound you want.

The first ENVELOPE SATURATION, to the right and above the MU knob, shows when the envelope signal begins to go into saturation, and gets brighter and stays on longer the more the envelope is "pushed" further into saturation. So when it NEVER lights up, the envelope always follows the shape of the loudness of your instrument signal, and never overloads. When it goes on only on the loudest notes or chords you play, it overloads at the peak of the signal, and from there, the more it goes and stays on, you know that you have "topped out" the envelope (making the filter sweep through its full range) with every note you play. All these settings and indications have musical uses, as I have discovered by playing different kinds of riffs into the TRU-3X.

The ENV SAT LED is only responsive to your signal and the setting of the MU control. The red numbers on the dial tell you that you will be hitting env sat with almost everything you play.

The other overload indicator, AUDIO DIST(ORT) responds when the audio signal to the filter hits clipping. This is a very different kind of thing because you will be able to hear the OP-AMP CLIPPING distortion and in the "middle ranges" of the MU control, it might or might not sound good to you... and the higher you set the MU control, the louder the audio signal gets, till it mignt be much louder than the BYPASSED signal from your instrument in TRU-BYPASS mode. But I have found that when the loudness is boosted so that it distorts almost ALL the time, it can (surprisingly!) make some very musical distortion tones when it goes through the filter , especially in SOME modes and settings.

But when you drive the audio to FULL DISTORT with the MU control, you also saturate the envelope(both lighty will go on) so every note is "slammed" to full sweep. This is not, in my opinion, optimum for many kinds of more subtle effects.

So... That's why the MU <-> PRE toggle switch between and below the MU and the PRE(AMP) controls is a new feature of the TRU-3X.


myFXDB user reviews

2 reviews, average score of 10 / 10

2015-12-1210/10  Beautiful design, wonderful sound, very adaptable to different styles, plays well with fuzzes in front of it, super funk-a-licious and sweetAlthough significantly smaller than the original, it still takes up a lot of space. Needs a dedicated power supply.
2014-01-1910/10  ......


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envelope-controlled envelope follower amplitude controlled fx pedal stompbox stomp box guitar effects pedal filter eq/excite/filter
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