Cognitive Dissonance Mk. 1

Cognitive Dissonance Mk. 1 (only 8 in existence? Maybe 10?)(mids switch)(released mid 2006 – Cog Dis #2 is dated 9-20-06)(retired when?)

Marc Says (via TGP)?
"Yes, the CogDis MkI was the same thing as a Mayonaise only in a small box. I had gotten a small batch of NOS 2N5133's that were used in that run."

"The first Cognitive Dissonance was a batch of 8 pedals made from NOS transistors I found on eBay (the kind found in early triangle-knob Big Muff Pi's)." "Marc Says (via TGP):?
    "The CogDisMkII was made from a batch of rare Japanese transistors I had gotten from Scotty Smith aka ProAnalog. The transistors were very high gain and bright but the circuit had extra treble filtering and negative feedback to compensate."

    "The CogDisMkII is angry and aggressive and never loses its biting fuzz no matter how low you turn the sustain knob. The transistors in it have their own personality, kind of an orangish-brown sound--gritty and thick, yet cutting and aggressive at the same time."

The first version was a very close clone of the original triangle-knob BMP with original-type NOS transistors.

The second version was a modified circuit using some rare, high-gain Japanese transistors.

The third version was re-jiggered to accept a modern, high-gain transistor and to keep a neutral tonal footprint, low noise, and excellent detail and articulation. Very suitable to a later-era Gilmour type distortion sound ala Division Bell. There were about 69 made of the MkIII.

Ernie Vs Cog Dis III:
They use the same type of transistors, and they’re both muff builds. The Ernie specializes from there in the areas of super fuzziness and sustain and “vintagey” voice. It’s inspiration was Ernie Isley; it’s an over-the-top early 70’s fuzz tone. The CogDisMkIII progresses from the muff foundation in the direction of refinement, balance, articulation, and usefulness, still with a warm voice–kind of a “does-it-all-very-well” muff build (if you wanted something that could cover both Gilmour and Corgan territories) rather than a specialty-voiced fuzz.

Nice! How does it compare to the earlier versions?

The first version was a very close clone of the original triangle-knob BMP with original-type NOS transistors.

The second version was a modified circuit using some rare, high-gain Japanese transistors.

The third version was re-jiggered to accept a modern, high-gain transistor and to keep a neutral tonal footprint, low noise, and excellent detail and articulation. Very suitable to a later-era Gilmour type distortion sound ala Division Bell. There were about 69 made of the MkIII.

The MkIV comes after the MkIII had been discontinued since 2015, and it is essentially an exact reissue, circuit-wise, of the Cognitive Dissonance MkIII. I had been planning to do a MkIV for some time, and as it turns out I found zero reason to make any changes from the MkIII for this new design. It is really nice as is! So I have the MkIV design already made for my screen printer (2 different versions of it), but in order to make more MkIII’s I’d have to use paper or water-slide decals. Nope. Better to start a new product name/serial # series if only because the silkscreened graphics are better than decals. 😀

Courtesy Marc Ahlfs

On that batch of Transistors for the 8 Cognitive Dissonance pedals:

Cognitive Dissonance – Period correct 1971 EH Big Muff Pi Clone. According to Marc, “the original Cognitive Dissonance was made with a batch of new-old-stock 2N5133 transistors I scored on eBay a couple years ago. Analog Man bid against me and underestimated my determination to get them. I gave him 4 anyway for a pedal he was making for some famous musician at the time. The rest went into that batch of 8 pedals. (Analogman replied in 2010 – ” Yes, I remember that! Marc was mighty nice, he even offered to build up a pedal for us. I still have those trans, a many more I have collected over the years, but for now I’ll leave the muffing to Marc”)