Fuzzy Meatball

[BRingoC]

My Mcmeat has a problem I think, the envelope is generating a fair amount of distortion when it runs through the mid-frequency area.  I have changed both chips a couple of times, and no change.  When the blend is set to bypass, there sound is fully clean as well.  On tracing the sound with the audio probe, the fuzz can be found on the lm1458 side of the circuit starting right at the sensitivity lug 2 and right through till the end of that part.  On the ldr side, the fuzz comes in after the 10uf cap at the beginning, and only when the envelope is activated, I am unable to find anything specific that could be wrong.  Is it possible to have overloaded the ldrs and fried them? Is shielded wire called for anywhere in the circuit?  Anyone else had this problem?  Other than the fuzz it works as it should.

[AndyA]

I have a similar problem with mine. I get an okish effect if I play extremely gently but if I play harder heavy heavy distortion occurs. It starts at pin 14 on the TL074, and as far as I can tell from audio probing it everything else works fine, just this crazy distortion in the first stage... Vcc+ into the TL074 is 7.8v and 0v (ground) at Vcc-

[AndyA]

Got it working now, was just a stupid short from a lead. This pedal is mad!

[BRingoC]

This thread is attached to the wiki for the McMeat/Meatball so I figured I would follow up on it.

I replaced three of the four Lorlin switches on my build.  This cleared up the majority of the noise and fuzzyness that was present before. I then replaced the footswitch and that cleared up the last remaining intermittent shorting out of the pedal.  I had built this pedal quite a while ago, and apparently had over done it with the soldering iron on those switches, which melted the interior components of them.  I replaced the Lorlin's with Alpha open frame switches.  On the Alpha's you can't set them to a certain number of stops, say 3 instead of 4, but when the 4th setting is selected the effect is shut off, no problem, just a little inconvenient.  The Alpha's do seem a bit more solid than the Lorlin's and should be worth considering when building this thing.

[jefe]

Thanks for the update! The Meatball has been on my to do list for ever. I even have all the rotary switches - they're plastic ones. I'll be sure to get in & out quickly with the soldering iron!