Laundryroom David
Keyboard Cowboy 🤠
As @Guardians of the analog has reminded us, the DS-1 is classic and essential. How ‘bout a PPCB version? I’d build it!
Upvote
11
Boss DS-1
- Thread starter Laundryroom David
- Start date
swyse
Well-known member
https://www.pedalpcb.com/product/defouler/
While not technically the same, the distortion section from the df-2 is very very close if you just want that sound.
While not technically the same, the distortion section from the df-2 is very very close if you just want that sound.
Laundryroom David
Keyboard Cowboy 🤠
Fair enough!Why build one for €50 with a TL072 when you can buy one for €40?
swyse
Well-known member
This is in progress.
Feral Feline
Well-known member
Why build one for €50 with a TL072 when you can buy one for €40?
... and besides, as swyse noted, it's "in progress"
Laundryroom David
Keyboard Cowboy 🤠
Fine, I’ll just build the one I want on vero 
Robert
Reverse Engineer
Interesting.
When I was prototyping the Patron Distortion (which is a modified DS-1) I tried a TL072 and 4558, both sounded terrible and off bias.
I retraced the circuit thinking I had made a mistake but found nothing.... Using the correct TLC2262 sorted everything out.
Last edited:
jesuscrisp
Well-known member
I wonder if snipping D3 would help
Robert
Reverse Engineer
I wonder if snipping D3 would help
Possibly, but Boss / MXR didn't so I didn't either.
It worked fine using the correct (in the case of the MXR) opamp.
I'll have to dig out the prototype and try the mods mentioned with a TL072 and 4558.
jesuscrisp
Well-known member
I just don't see WHY it would bias weirdly with both....
Robert
Reverse Engineer
I agree. It certainly wasn't my first suspicion.
I built one, it sounded awful. I swapped the transistors and opamp, didn't help.
By this time I didn't have the original anymore to compare against so I had to get another one, also just to confirm that it wasn't supposed to sound like that. Retraced it, everything was correct.
Built a second one. Same thing.
The only difference was that I wasn't using a TLC2262... ordered one, popped it in and it cleared right up. Swapped back to TL072 / 4558 (both genuine), the problem was back.
I'm not sure how this translates to the stock Boss circuit, but in the case of the MXR the TLC2262 was critical. (unless, of course, you want it to sound like a broken Superfuzz)
Guardians of the analog
Papi Fuego
I went through this issue when I built my aion comet and documented it in my build report. Aion suggested the 4580 in the build doc but also claim the 4558 and 072 as substitutes. I found all 3 sounded like you said, like an octave fuzz reminiscent of a super fuzz. I did some deep dives on schematics and versions that switched to the dual opamps. the njm2904 and njm3404 were both used by boss. I only had a 2904 on hand at the time and using that got the classic DS-1 sound. This is one of the only times building a boss pedal that I felt opamp selection was truly crucial.
jesuscrisp
Well-known member
I still stick to the fact that it makes zero sense. If anybody has time, can you check if the op amp biases correctly with the right and wrong op amps respectively?
Maybe it's some weird impedance/op amp architecture thing that makes the IC misbias starting at the input coming off the transistor boost, and then the entire dual op amp is directly coupled. I'd kind of suspect it's either the diode from ground, 100K bias and 47K series resistor acting as a voltage divider that causes the misbias or both. Would wonder whether increasing the bias resistor substantially to like 470K to 1M and snipping the diode (really doesn't need to be there anyway) would fix it.
Maybe it's some weird impedance/op amp architecture thing that makes the IC misbias starting at the input coming off the transistor boost, and then the entire dual op amp is directly coupled. I'd kind of suspect it's either the diode from ground, 100K bias and 47K series resistor acting as a voltage divider that causes the misbias or both. Would wonder whether increasing the bias resistor substantially to like 470K to 1M and snipping the diode (really doesn't need to be there anyway) would fix it.
jesuscrisp
Well-known member
No offense but I doubt slew rate has anything to do with this
Similar threads
