This Week on the Breadboard: Shallow Water

[Chuck D. Bones]

Should not be noisy. There could be many causes and this is not a troubleshooting thread.

In other news, I tried adding feedback around the BBD like we would find in a flanger. Very interesting. It magnifies the vibrato effect and with a lot of feedback, we get that "talking thru a vacuum cleaner hose" tone. Right now I have the feedback is controlled by a knob, butt-eye think a 3-way toggle switch will do: No Feedback, Moderate Feedback, Heavy Feedback.

 

[giovanni]

Boneyard edition would be awesome! I am in the process of building it stock but your mods seem really good.

 

[mdc]

I don't get why Fairfield adds gain in the first stage and then takes it all away in the BBD's input filter. I also don't understand why Fairfield runs the V3207D & CD4046 on 5V when they work as well or better on 9V. Definitely more headroom in the BBD at 9V. The input and output preamps work perfectly well, but could have been implemented by a dual opamp. There is a significant volume shift when turning the MIX knob from Dry to Wet. Not sure why Fairfield did that.

Cool work, just on this note - it would be easy enough to ask him and find out. Guillaume is a mellow guy, he's shared schematics and is pretty open about their stuff.

 

[Chuck D. Bones]

Here's the latest update.

I added S2, C20, C21, R16, R17 & TR4. Nothing else except the notes changed on sheet 1 and nothing changed on sheet 2. If you turn Fdbk Trim up enough to cause oscillations, IT WILL GET LOUD. I might add a pair of clipping diodes in the feedback path.

 

[giovanni]

Chuck, any chance you could record an audio clip of the pedal with your mods?