Question for MKII builders (B. Tremblay?)

[phillip]

I've been messing around with different transistors in my newest MKII, and I can't get the thing to clean up when the Attack knob is turned all the way down to save my life.

The question is...how much distortion is the MKII (all Germanium) supposed to have with the Attack control turned all the way down (counter clockwise)?

TIA!
Phillip

[B Tremblay]

My MkII clone, with all germaniums, has a nice range to the Attack control.

At minimum, it's crunchy with decent clarity and cleans up with the guitar volume.  There's a sweet spot around 10:00 or so, which I usually dial in by hitting the 12th fret harmonic of the D string, letting it ring while turning the knob.  The harmonics of the pedal will suddenly come into focus and that's where I'll leave it much of the time.  

Towards maximum Attack (past 3:00), the pedal will feedback with my single-coil bridge pup unless I turn down the guitar's tone control.  The sound is quite saturated, especially with humbuckers.

I'm not sure why your pedal doesn't exhibit the same range.  I've most recently been using a combination of Small Bear matched and salvaged car radio trannies, so I can't point to any specific part numbers for tonal bliss.

Could the bypass cap at the Attack control be leaky or mis-wired?  Are you using a trimmer for the collector of Q3?  What's the bias voltage there?

[phillip]

Thanks for the help, B.  Yours sounds like mine, with the crunch at minimum.  I haven't played through a real Colorsound MKII, so I wasn't sure if it was supposed to clean all the way up.

I usually play mine with the Attack turned to about 2 o'clock with the guitar's volume control rolled off a bit...gives a good maxxed out Fuzz Face sound but with more "oomph," but it has even more fuzz available just by rolling the volume back up.  

I ended up replacing the 8K2 on the collector of Q3 with a 12K (using a pair of sockets) to get the voltage down to a more "correct" level.  Q3's collector measures a tad over 5V with the 12K.

Phillip

[phillip]

I just opened the box back up and measured the resistance across the 4.7uF bypass cap on the Attack control...1.4 ohms with the Attack turned all the way down, and 1K9 with it turned all the way up (I used a 2K pot for the Attack).  Something rotten in Denmark!  I know that a good electro. cap should go to nearly infinite resistance quickly when measured with a DMM.  

I used the continuity function of both my DMMs (just in case) and tested the cap by placing one lead on the anode and the other lead on the cathode...they tested as continuity...a shorted cap.  Looks like it got a little too hot when I was soldering the lead from there to the Attack control.  Doh!

Phillip