Eric Johnson/Larry Carlton ODS build

[DSull89]

You’re absolutely right, EJ’s main sound is a 100w Marshall and his dirty rhythm amp from the early 80’s until the mid 90’s was a SSS. Only reason I used his tone on Zap as a way of describing what I was looking for tone wise was because when HAD passed this past January, EJ divulged that Zap was recorded on an ODS and a 335.

[talbany]

Not that it necessarily matters, as I think I understand what you are looking for, but at least as far as EJ goes, those lead tones are all through his Marshall 100W. The Dumble was used at that time as his crunch rhythm sound. He has a tube driver into an echoplex and into the Marshall for that signature lead sound

Here is a rare video of E.J 1985 with the ODS Playing ZAP. Twins for the clean sound. the SSS (Tube Screamer/MXR) for the dirty rhythm and his ODS (in O.D) Through an echoplex into a Marshall 2 or 4X12 cab for lead work. No Marshall heads around. He talks a little about recording Tones.


https://www.youtube.com/watch?v=VCy7NLGl2_8&t=997s

[Chris Brown]

Not that it necessarily matters, as I think I understand what you are looking for, but at least as far as EJ goes, those lead tones are all through his Marshall 100W. The Dumble was used at that time as his crunch rhythm sound. He has a tube driver into an echoplex and into the Marshall for that signature lead sound

Here is a rare video of E.J 1985 with the ODS Playing ZAP. Twins for the clean sound. the SSS (Tube Screamer/MXR) for the dirty rhythm and his ODS (in O.D) Through an echoplex into a Marshall 2 or 4X12 cab for lead work. No Marshall heads around. He talks a little about recording Tones.


https://www.youtube.com/watch?v=VCy7NLGl2_8&t=997s

It's almost laughable how much he sounds like himself whether he's playing through a Dumble, or through a Fuzz Face into a Marshall!

[DSull89]

Not that it necessarily matters, as I think I understand what you are looking for, but at least as far as EJ goes, those lead tones are all through his Marshall 100W. The Dumble was used at that time as his crunch rhythm sound. He has a tube driver into an echoplex and into the Marshall for that signature lead sound

Here is a rare video of E.J 1985 with the ODS Playing ZAP. Twins for the clean sound. the SSS (Tube Screamer/MXR) for the dirty rhythm and his ODS (in O.D) Through an echoplex into a Marshall 2 or 4X12 cab for lead work. No Marshall heads around. He talks a little about recording Tones.


https://www.youtube.com/watch?v=VCy7NLGl2_8&t=997s

It's almost laughable how much he sounds like himself whether he's playing through a Dumble, or through a Fuzz Face into a Marshall!

It's proof that tone is in the hands and mind. There's a video where he's playing a clinic and sounds the same through a Blackface Deluxe and a Mad Professor Golden Cello. Doesn't matter what he plays through, he's always gonna sound like that. I will say, though, that in my opinion, the best fuzz sound he ever had was with the SSS. The air that rig moved must've been an experience to witness live. Incredible.

[imo1]

It’s true. I played a number of times with him, as well as spending time at his studio, around then. He would sometimes sit in playing a fender as well and to me it sounded almost the same as when he would play the full rig. When I tried his set up it sounded nothing like him

[DSull89]

Hey guys! I have a small update for this thread. Got the pcb from AA and it looks great! I’m almost done compiling the BOM with CE part numbers and will post it when I finish it tonight or tomorrow. I think I’m going to do the FET footswitch MOD, does anybody know where to get the necessary board for the third relay?
Thanks,
Dan

[pompeiisneaks]

Hoffman Amps has a great little relay board you could use. It doesn't match the original dumble one where it pulls all the pins onto one side, it instead has them on the side they live on in the relay.

https://el34world.com/projects/relay_switch.htm

They've worked amazingly well for me.

~Phil

[DSull89]

Thanks Phil! That looks like just what I need! I was at the music store today and they had a bunch of old parts kicking around in back. He’s got tons of old carbon comp resistors and these two old 12v relays. I know there’s been a zillion posts about carbon comps, some like them and some don’t. Can anybody say definitively where carbon comps work best in the 102 circuit if at all? Also, will these relays work in there?
Thanks,
Dan

[DSull89]

Hi guys! Been a while, I've been researching my tail off so I understand what I'm doing when I finally touch solder to iron in the next few weeks. I have a quick question about the 12v transformer for the relay supply. I got a hammond 166F12B for this and was wondering if the center tap needs to be grounded or not? I noticed the rectifier circuit on this pcb looks very different from the full wave bridge on the boards that most of you use for your builds. Any input is greatly appreciated.
-Dan

[Guy77]

Hi. I also used a Hammond transformer similar to yours to power my relays (166xx series) with the 2 green wires and one stripped CT wire.
I did not connect the CT wire. Instead I just used the ground connection on my relay boards and it worked perfectly.

Cheers

G

[DSull89]

Thanks, Guy! I appreciate the response! I ended up going for the beefier 166JA12 transformer for the relays. I’ve got virtually everything aside from a few elusive/overpriced parts that are giving me the runaround. Definitely a lot more difficult than compiling the parts for a Marshall build. Lol
-Dan

[martin manning]

The PCB appears to be set up as a voltage doubler, with two diodes and 3 caps. A 6.3 VAC input will then get ~16 VDC into a 12V regulator. I believe I have seen a hack to set it up as a full-wave bridge with four diodes and two caps so a 12.6 VAC input will yield about the same DC level at the input to the regulator. You could do it either way with your 12.6 VAC CT secondary.

[DSull89]

Thanks for the info about the rectifier, Martin! I’ve been scouring the forum for the right info but it’s still kinda tough for me without a command of a lot of the electronics theory and troubleshooting knowledge. I’m by no means an amp builder. Would you mind sharing in detail the two possible wiring schemes for the relay supply and rectifier on the pcb when you get a chance?
Thanks,
Dan

[martin manning]

I don't recall exactly where I saw the full-wave bridge hack, but two diodes and a jumper were added, and one cap was deleted. It'd be easy to work something out if the traces were visible. I would just use it as is, and feed it 6.3 VAC as designed from your transformer by connecting the CT and one of the other leads (doesn't matter which one). It will look like this:

[DSull89]

Thanks, Martin! This was a big help!