OD 386

[caspercody]

Last night I found a schematic on line for OD 386. I do not remember what web site I was on. This was designed by Eric Scheie, and dated 10/2/02008. It looks really interesting and I am asking if anyone knows about this? I have the jpeg file of it.

[Electron Tornado]

The OD 386 is an overdrive using the 386 op amp and was developed from the Smash Drive by Aron Nelson and the Grace Overdrive from Runoff Groove. The tone section is from the Big Muff, modified to enable the user to select mids that are humped, flat, or scooped. The last section is an amplifier to boost the signal. The switch for the capacitors at the input to the op amp is a "fat" switch. All the clipping is done by the op amp.

[caspercody]

Do you know if there is a pcb layout for this? Or any sound clips?

Thanks for theinformation!

[Hupla]

http://www.runoffgroove.com/salvo.html

Theres a clip of the grace overdrive here which im sure it sounds alike.

[Mark Hammer]

Not to take anything away from the people mentioned, but to the best of my knowledge, the very first pedal to use a 386 as a distortion element was the Frantone Hep Cat. Was it the "best" use of a 386 in that capacity.  Don't know, never heard one.  But it was kicking around for a couple years before 386-based pedals started to become a source of intrigue for people.

[caspercody]

I made the Grace, and it is a great pedal. I am now trying different tonestacks with it.

It has a little fizzle decay sound to it at low gains, not sure if that is common or not? Tried different Jfets, and 386 but still does it.

I am liking the sound of the 386 (made Krank, Grace, and Purple Plexi) and ran across this schematic for the OD 386 and looked different than any other 386 pedal. Just trying to find more info on this to decide if I want to build it.

So far to me the 386 sounds like it could be a great low gain distortion pedal. I know it is great for high gains.

[Electron Tornado]

Do you know if there is a pcb layout for this? Or any sound clips?

Thanks for theinformation!

I don't have any sound clips, but I do have PCB layouts for it. I can email them to you if you like, but you'll have to wait until the beginning of December when I can get to them.

[caspercody]

Yes if you could email them to me that what be great.

Thanks
Rob

[Electron Tornado]

Yes if you could email them to me that what be great.

Thanks
Rob

OK, will do when I get back in December. In the mean time, will you be breadboarding it?

[caspercody]

No, I do not have a breadboard. I just prefer to do a pcb board. I want to try to figure out how to use one of the programs to create my own pcb boards.

[grolschie]

It has a little fizzle decay sound to it at low gains, not sure if that is common or not? Tried different Jfets, and 386 but still does it.

I built a pedal based on a Ruby, with a BMP tonestack, volume knob at output, and an EA boost in front. Sounded pretty good, good range of sounds, massive distortion, but the crackle on  the decay ruined it for me. Maybe running it full tilt into an output buffer might solve it?

[Electron Tornado]

Yes if you could email them to me that what be great.

Thanks
Rob

Rob,

Sorry for the delay.     Work and the holidays kept me on the road most of December as well. I have the PCB trace, layout, wiring diagrams, and some notes ready. I sent you a PM. Thought I'd give this a bump as well.

If anyone else is interested, PM me with your email. Everything is on a couple of Word docs.

[oliphaunt]

I have googled all over but can't find anything on the OD 386.  I would love to see a schematic for this.

[Electron Tornado]

Here's a link:


http://img163.imageshack.us/img163/9281/od386v21schematic.jpg

[deathfaces]

pm'd

[oliphaunt]

Electron Tornado, thanks for the link to the schematic.  I am a little fuzzy about the switching for the mids.  It may make more sense once I get it on a breadboard, but if anyone has any basic description that might help.

[Electron Tornado]

Electron Tornado, thanks for the link to the schematic.  I am a little fuzzy about the switching for the mids.  It may make more sense once I get it on a breadboard, but if anyone has any basic description that might help.

Look at the schematic and the notes for the switch in the tone section. You can also put those component values into the Tone Stack Calculator from Duncan Amps and see graphically what is going on. That might help. Remember, the tone control is just a modified Big Muff tone control.

Keeping the tone control pot centered - In one position of the mids switch, there will be a "hump" in the middle of the frequency range and the mids will be emphasized. In another position, the graph of amplitude vs. frequency will be flat, with all frequencies getting equal emphasis. In the last position, there will be a big "scoop" in the middle of the frequency range where the mids are dampened.

For the mids switch, it is a two pole, three position (On-On-On) switch. Make sure you get the data sheet for the switch you use so you can see how the lugs are connected in each switch position. (Maybe I should go back and add more to the wiring diagram about the switch I used. )

[artsinbloodshed]

hey!
I went with the regular grace design and added the tone stack.It pops like hell!
I disconnected the tone stack part and still pops.
I changed everything from switch to pulldown resistors to led through 3pdt wiring with no change...
Does anyone have encountered that problem?