Morbidpale
Well-known member
I bought H11f1's from digikey (x10 purchased) and mouser (x10 purchased). I ran the test on them per the helpful Chuck D Bones (https://forum.pedalpcb.com/threads/pandoras-box-fizzle.25875/post-329869). I'm looking for an approximate range of 320mv to 2.5v. What I get is 1.8v to 7.1v. I tested most of them and they are very consistent. Now this was a problem back when i was working on an Expandora but for now i have the DBA Evil Filter on a breadboard. I couldn't say exactly if its a "problem" here since, you know, Oliver. I'll circle back to that in a sec.
To attempt to force the optocoupler to work within the numbers provided by C.D.B., I changed the 1k resister on pin 1 to 2.8k. Now my range is 0.47mv - 2.7v. Pretty good! In the evil filter schematic i changed R14,15 from 1k to 2.7k. Definitely makes a difference at the far ends of the pot settings. What an Evil Filter sounds like off the shelf i don't know. What Oliver intends or if his h11f1's are in spec i don't know. I'm going to play with it until i like it. The Expandora NEEDED adjusting to sound its best but this circuit can go with the flow a lot better.
Question is:
Is this a reasonable method to adjust for the specs of these specific components?
Is this component just made this way now?
In the Expandora I changed R17 from 4k7 to 10k to eliminate my "fizzle" issue with note decay. Bear with me, 10k is roughly double the 4.7k. 2.7k is more like triple the 1k but is there a proportional relationship I should be seeing? or did 10k work because I used my ear/potentiometer combo and got lucky?
To attempt to force the optocoupler to work within the numbers provided by C.D.B., I changed the 1k resister on pin 1 to 2.8k. Now my range is 0.47mv - 2.7v. Pretty good! In the evil filter schematic i changed R14,15 from 1k to 2.7k. Definitely makes a difference at the far ends of the pot settings. What an Evil Filter sounds like off the shelf i don't know. What Oliver intends or if his h11f1's are in spec i don't know. I'm going to play with it until i like it. The Expandora NEEDED adjusting to sound its best but this circuit can go with the flow a lot better.
Question is:
Is this a reasonable method to adjust for the specs of these specific components?
Is this component just made this way now?
In the Expandora I changed R17 from 4k7 to 10k to eliminate my "fizzle" issue with note decay. Bear with me, 10k is roughly double the 4.7k. 2.7k is more like triple the 1k but is there a proportional relationship I should be seeing? or did 10k work because I used my ear/potentiometer combo and got lucky?
