Circuit-Bent Radioshack Delay Demonstration

Published on Oct 24, 2015 nounandnumber

"Video made to accompany an eBay sale. The following modifications have been made:
- Replaced the line out phono sockets with standard jack sockets.
- Added a switch to allow delay feedback at full saturation (a connection between R20 and R25). This reduces the feedback level when the saturation is set low, however.
- Added a momentary switch to create a "punch in" feedback saturation button (connection between R20 and Jumper 4).
- Added a momentary cut to the inputs. As the mic and line inputs follow two routes, a switch has been added to select between the two.
- Created a touch point to slow the delay speed. This is a connection between C23 and ground and (I think) bleeds the resistor charge. It does come with a high-pitched whine when bled though.
- Replaced the original 4558 op amps with socketed 4580s (after reading about it here: http://zerotronics.com/rsrvb/). Looking at the before and after audio's spectral frequency seems to show a slight reduction in noise around 2kHz, but it is barely noticeable to be honest."