Original effects with schematics, layouts and instructions, freely contributed by members or found in publications. Cannot be used for commercial purposes without the consent of the owners of the copyright.
Hi folks
Here is a little overdrive / distortion pedal I knocked up on veroboard earlier this evening. Based on a modified Boss DS-1 with an active high and low tone control section - sounds really nice and simple to build. I may get some boards fabricated if sufficient interest in building it, in the meantime here is the schematic and picture of the finished verified pedal.
cheers
bajaman
Interesting looking tone control. What is the 22n cap in parallel with the 3.3K resistor doing? What is there frequency response of the Bass and Treble controls?
Interesting looking tone control. What is the 22n cap in parallel with the 3.3K resistor doing? What is there frequency response of the Bass and Treble controls?
tone control is lifted from the Tech 21 character series pedals - the 22n capacitor rolls off the high end response - when the controls are set to midway the 22n capacitor in conjunction with the 120p capacitor rolls the high end off by -3dB at 8kHz. When the high control is fully clockwise there is approximately 12db of boost at 2.6KHz and the 22n capacitor ensures that there is a steep roll-off above this frequency
The low control has a similar amount of boost (and cut) at 85Hz.
When both controls are fully clockwise there is a broad dip in the response curve centred around 620Hz and a 3db boost at this frequency.
When both controls are fully counter clockwise there is a broad hump in the response curve centred around 660Hz and a 3db cut at this frequency.
cheers
bajaman
After building the AFD, I decided to build this last night on my breadboard. WOW - another great design that sounds wonderful - even better than the Mesa Flux Drive I built on vero recently. Thanks again Bajaman! I used LEDs for the clippers and a TL074, but otherwise everything the same as the schematic.
I also created an LTSpice sim for this circuit, and it's hard to believe that the original Boss DS-1 had a 22 ohm emitter resistor in the transistor gain stage (I assume this is true of the modern versions too). That must be what produces the nasty fizzy distortion characteristic of all DS-1 pedals. But I suppose Boss thought that the fizz is so bad that it's good...
Built my vero version of the Highway 1 over the weekend and it works great. Tone controls are very effective. I used my own layout with a single TL064 chip. It's not as compact as Alex's layout so I won't post it unless someone wants to see it. Thanks again, Bajaman - nice design.
Thank you!
I'd like the idea of this circuit, but I don't know if I'm going to build it so soon.
Does it sound close the DS-1? I just see that eq is difference and not scooped like the original DS-1. No demo anywhere, I guess.
Ichabod_Crane wrote: ↑25 Aug 2020, 14:08
Thank you!
I'd like the idea of this circuit, but I don't know if I'm going to build it so soon.
Does it sound close the DS-1? I just see that eq is difference and not scooped like the original DS-1. No demo anywhere, I guess.
Seems to me the different clipping diodes will give a different tone overall.
"Analog electronics in music is dead. Analog effects pedal design is a dead art." - Fran
Yes, I chose red LEDs but you can experiment and decide what you like. I'll see if I can locate my build, but my recollection was that it was not as "buzzy" as the original DS-1 but more of a mid-range distortion.
Frank_NH wrote: ↑25 Aug 2020, 18:24
[...]
I'll see if I can locate my build, but my recollection was that it was not as "buzzy" as the original DS-1 but more of a mid-range distortion.
Yes, more mid-range it was I meant.
I never tried directly, just heard some demo, but I like the DS-1 with mosfet clipping. I don't remember any pedal with BC547B or kind of as signal clipping. What's the difference with more common silicon diodes?
I used LEDs for the clippers and a TL074, but otherwise everything the same as the schematic.
