MXR - Flanger/Doubler ( M-126 )  [schematic]

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Re: MXR - Flanger/Doubler ( M-126 )

Postby Dirk_Hendrik » 14 Jan 2012, 23:05

Mine suits the application. Thanks mr Tripps!
Sorry. Plain out of planes.

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tube-exorcist (04 Mar 2012, 17:48)
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Re: MXR - Flanger/Doubler ( M-126 )

Postby sadrew » 10 Dec 2014, 18:21

i have one of this great sounding delays and unfortunately it has developed a noise issue

i can hear the effect flanging but there is a loud motorboating noise too

the noise disappears in bypass or when the mix knob is in dry position

i already recapped the unit with fresh electrolytics but the noise is still there

i tried to probe the circuit and the noise is pretty much everywhere. i can hear it in the +12V rail as well

on U10 pin 1 there is noise when the regen pot up is turned up. with regen at minimum there is no noise in that point of the circuit

i am trying to narrow the area where the noise builds up but this is a complex circuit for my skills and at the moment i can't figure out a solution

if anyone can help me understanding the schematic and how to nail the problem i would really appreciate

i re attach the schematics for reference

thanks !
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Re: MXR - Flanger/Doubler ( M-126 )

Postby kieganlenihan » 04 Jun 2018, 20:19

Hi everyone! I am new to this site and I apologize for kicking such an old topic. I have one of these units already, and I am absolutely loving it. The one problem with it is that it runs exclusively in Mono. I have two EVH 5150 III Stealth Amps with the same Mesa 4 x 12 Cab and the lead channel with some delay and the doubling effect from the MXR M-126cis simply beautiful. If I run this effect into my two amps, I don't really get true stereo, I just get dual mono. The reason for the long winded introduction is because I have read online the VC inputs are used as voltage control lines to connect two units in tandem. Does anyone have experience doing this? And if so how would I go about connecting these two units together so that they form 1 true stereo unit?


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Re: MXR - Flanger/Doubler ( M-126 )

Postby Fender3D » 05 Jun 2018, 19:42

kieganlenihan wrote:...If I run this effect into my two amps, I don't really get true stereo, I just get dual mono...

Welcome to FSB mate,

This effect IS mono, it has low and high sensitivity inputs and outputs but they carry the same signal (in different levels of course).

kieganlenihan would I go about connecting these two units together so that they form 1 true stereo unit?

...hmm I think unit1's CV out into unit2's CV in would work....

You might connect it from amp1's SEND to amp2's return;
setting the MIX control fully or almost fully WET you get pseudo-stereo sound when effect is engaged and dual mono when disengaged,
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