G.G.
Well-known member
Finally finished up these MKIs I've had on the bench for several months. I love them!! These are generic PNP sets I got recently from Small Bear. I started out with them in the MKI circuit on a breadboard (first time breadboarding for me). I created on layout on perf (another first for me) and used a Madbean Road Rage for the voltage inverter on both. The silver one is mostly using the original 1965 specs (subbed a 1.8M for the 2.2M resistor) and the Gold is built to Castledine specs. Here are some pics and a vid with them both and a MKI with an OC75 set I built quite a while ago to Gary Hurst specs. More info after the pics for those interested in my MKI journey. 
First off I have to recognize Andy and his Guitar Effects Blog. His MKI spreadsheet and notes were an invaluable resource. https://vero-p2p.blogspot.com/
So yeah, MKIs. Setting up the Small Bear sets on the breadboard was actually the easiest part. Pretty painless and both sets worked great right away using the stock values on the paper schematic they ship with. After listening to some demo vids from Macari's I wanted to go with the Castledine specs, which sounded great on the breadboard, but when I tried to plug my components into an already existing vero layout I thought I burnt up my transistors because it sounded bad. So I ordered another set. While I was waiting for them I did more testing and ended up recreating the circuit on the breadboard. Turns out the transistors were fine and I must have botched the vero build somehow even though I went over it about a million times and never could spot the problem. Seemed easier to just make my own perf layout at that point. I had a vero voltage inverter in the silver one which worked fine until one day it didn't, just overheated and burnt up. I put a RoadRage in and was getting really bad 9v noise and that's why that one has the grounded input and output cables. Turns out I had a bad MAX1044 and when I swapped that out the power noise went away. So yeah, several months later I have MKIs. The Gary Hurst version seems to have the most range on the Attack knob, and the most MKI "artifacts." The other two don't have a whole lot of range on the Attack even though I went with a Log pot, but both have more presence and get really great pinch harmonics. They're all a little different and all awesome, was definitely good to finally be able to close the lid on those.
First off I have to recognize Andy and his Guitar Effects Blog. His MKI spreadsheet and notes were an invaluable resource. https://vero-p2p.blogspot.com/
So yeah, MKIs.
Setting up the Small Bear sets on the breadboard was actually the easiest part. Pretty painless and both sets worked great right away using the stock values on the paper schematic they ship with. After listening to some demo vids from Macari's I wanted to go with the Castledine specs, which sounded great on the breadboard, but when I tried to plug my components into an already existing vero layout I thought I burnt up my transistors because it sounded bad. So I ordered another set. While I was waiting for them I did more testing and ended up recreating the circuit on the breadboard. Turns out the transistors were fine and I must have botched the vero build somehow even though I went over it about a million times and never could spot the problem. Seemed easier to just make my own perf layout at that point. I had a vero voltage inverter in the silver one which worked fine until one day it didn't, just overheated and burnt up. I put a RoadRage in and was getting really bad 9v noise and that's why that one has the grounded input and output cables. Turns out I had a bad MAX1044 and when I swapped that out the power noise went away. So yeah, several months later I have MKIs. The Gary Hurst version seems to have the most range on the Attack knob, and the most MKI "artifacts." The other two don't have a whole lot of range on the Attack even though I went with a Log pot, but both have more presence and get really great pinch harmonics. They're all a little different and all awesome, was definitely good to finally be able to close the lid on those.
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