Grateful Dead Music Forum

Hey all. Found this thread in my search for any mods or settings for a MKIIa

I picked one up last year (MKIIa, reverb but no GEQ) in my hopes of finding a middle ground that would give me both the early ‘76 and winter ‘79/‘80 tone.

I’ve tried the settings shared above, but I’m still having trouble dialing in a thick, round tone (think: Orpheum ‘76 or Keane ‘80). I know there was a link posted above by someone who decided to delete said links a while back- did anyone happen to download those mods before they were deleted? If so, hoping they’d be kind enough to share.

Or, if anyone has any other ideas outside of what’s been mentioned above, I’m all ears.

Sean

Personally, my $0.02 is to not worry about the settings. Each amp is a little different and Jerry was using them at multi-thousand seat venues combined with his playing style. All about what fits best for us and our environments.

If you’re looking for something to thicken the sound a bit, this is my personal favorite current overdrive pedal. It’s incredibly natural (much more so than Tubescreamers and Earth Drive type pedals). It literally adds this thicker dimension to the music. Might be worth a try! It’s not the cheapest pedal, but it does work very well at emulating natural tube drive when the gain is pushed and also like a thick boost when the gain is lower…I like to keep the mid knob pretty low for a more transparent sound.

https://reverb.com/marketplace?query=Nordland+ODR-C

Tacosauce wrote: ↑Mon May 05, 2025 9:48 am Hey all. Found this thread in my search for any mods or settings for a MKIIa

I picked one up last year (MKIIa, reverb but no GEQ) in my hopes of finding a middle ground that would give me both the early ‘76 and winter ‘79/‘80 tone.

I’ve tried the settings shared above, but I’m still having trouble dialing in a thick, round tone (think: Orpheum ‘76 or Keane ‘80). I know there was a link posted above by someone who decided to delete said links a while back- did anyone happen to download those mods before they were deleted? If so, hoping they’d be kind enough to share.

Or, if anyone has any other ideas outside of what’s been mentioned above, I’m all ears.

Sean

Just double checking you tried two things. Pull out the treble control to shift the mids down which can sound thicker. Pull out the Master 1 which adds a ton of low end and fattens up the sound though may not be what you want and doesn’t seem very “Jerry”.

Another subject - Did you try the preamp out jack under the chassis to feed your McIntosh?

Slewfoot2000 wrote: ↑Tue May 06, 2025 9:40 am Personally, my $0.02 is to not worry about the settings. Each amp is a little different and Jerry was using them at multi-thousand seat venues combined with his playing style. All about what fits best for us and our environments.

If you’re looking for something to thicken the sound a bit, this is my personal favorite current overdrive pedal. It’s incredibly natural (much more so than Tubescreamers and Earth Drive type pedals). It literally adds this thicker dimension to the music. Might be worth a try! It’s not the cheapest pedal, but it does work very well at emulating natural tube drive when the gain is pushed and also like a thick boost when the gain is lower…I like to keep the mid knob pretty low for a more transparent sound.

https://reverb.com/marketplace?query=Nordland+ODR-C

Thanks for the suggestion. I think I actually came across another thread where you had suggested that same pedal? I seem to remember reading about it recently. No room on the board right now for a new pedal but if I get to that point I’ll consider it.

BoogieMK2 wrote: ↑Tue May 06, 2025 9:54 am

Tacosauce wrote: ↑Mon May 05, 2025 9:48 am Hey all. Found this thread in my search for any mods or settings for a MKIIa

I picked one up last year (MKIIa, reverb but no GEQ) in my hopes of finding a middle ground that would give me both the early ‘76 and winter ‘79/‘80 tone.

I’ve tried the settings shared above, but I’m still having trouble dialing in a thick, round tone (think: Orpheum ‘76 or Keane ‘80). I know there was a link posted above by someone who decided to delete said links a while back- did anyone happen to download those mods before they were deleted? If so, hoping they’d be kind enough to share.

Or, if anyone has any other ideas outside of what’s been mentioned above, I’m all ears.

Sean

Just double checking you tried two things. Pull out the treble control to shift the mids down which can sound thicker. Pull out the Master 1 which adds a ton of low end and fattens up the sound though may not be what you want and doesn’t seem very “Jerry”.

Another subject - Did you try the preamp out jack under the chassis to feed your McIntosh?

Hey Boogie. I actually pulled the amp out earlier this week to give that underchassis jack a try but apparently mine doesn’t have the jack marked like I’ve seen on other mesas (you know, like in sharpie?). There is this panel on the bottom of the back of the amp (see photo below) though that offers a diagram of the tube layout and other stuff: note #4, “effects send on bottom left.” This is the jack that I’ve seen on other mesas marked “pre amp out” in sharpie. Is this the jack that I should use?

Re: pulling the master and treble knobs out, yes, I usually run the amp with those pulled out 100% of the time. You’re right, it does help, but I still don’t feel like it’s giving me that round tone that I hear when I listen to 76 Jer.

Use the effects send (#4). I don’t think mine is label either.

Slewfoot2000 wrote: ↑Tue May 06, 2025 9:40 am Personally, my $0.02 is to not worry about the settings. Each amp is a little different and Jerry was using them at multi-thousand seat venues combined with his playing style. All about what fits best for us and our environments.

If you’re looking for something to thicken the sound a bit, this is my personal favorite current overdrive pedal. It’s incredibly natural (much more so than Tubescreamers and Earth Drive type pedals). It literally adds this thicker dimension to the music. Might be worth a try! It’s not the cheapest pedal, but it does work very well at emulating natural tube drive when the gain is pushed and also like a thick boost when the gain is lower…I like to keep the mid knob pretty low for a more transparent sound.

https://reverb.com/marketplace?query=Nordland+ODR-C

Bought the odr cs based off your comments, wow its insane i took it off my board to try other pedals, went out the house and was just thinking dam as soon as i get home i'm putting it back on its INSANE. Adds a such a flavor i didn't think overdrives have. Sort of changed the way i view overdrives since i dont like much gain since jerry didnt have a real overdrive sound but turn the gain down and its just like seasoning your food.,

Hooray and so glad you like it! Just the right amount of seasoning is a great way to describe it. And it’s super versatile with the knobs for mid, spectrum and lo-cut.

Enjoy the ride!

Slewfoot2000 wrote: ↑Sun Sep 28, 2025 3:28 pm Hooray and so glad you like it! Just the right amount of seasoning is a great way to describe it. And it’s super versatile with the knobs for mid, spectrum and lo-cut.

Enjoy the ride!

Any other pedals you would recommend, I went on a 'little' bit of a spre. So far I have the farm pedals boost of dead, nordland odr cs, thick air, barbershop, gain changer, Lightspeed, solar flare, venuram shanks, golden Royale, enigmatic 82, 29 pedals euana/oamp, Strymon flint, qtron +. I know I'm missing a phaser but haven't really played anything needing one so far.

Really want to swap my twin reverb out for a aviator mach 3 and also change the pickups on my Eastwood wolf to have dual sounds distortion on middle.
Cheers

Quitypop wrote: ↑Mon Oct 06, 2025 9:21 pm

Any other pedals you would recommend, I went on a 'little' bit of a spre. So far I have the farm pedals boost of dead, nordland odr cs, thick air, barbershop, gain changer, Lightspeed, solar flare, venuram shanks, golden Royale, enigmatic 82, 29 pedals euana/oamp, Strymon flint, qtron +. I know I'm missing a phaser but haven't really played anything needing one so far.

That's a lot of pedals to cop Jerry's tone, especially since he didn't use a single one of them!

Quitypop wrote: ↑Mon Oct 06, 2025 9:21 pmReally want to swap my twin reverb out

That's the first piece of gear you mentioned that Jerry did use and you want to swap it out.

First off, I think you need to decide if you want to copy Jerry's tone or come up with your own that is Jerry influenced but different. It sounds like you want to do the first but you are actually doing the second. Either answer is fine, but it helps if the direction is clear.

I can vouch for the Aviator Mach 3. Covers a lot of territory. Love mine!

Bill, tgo

Quitypop wrote: ↑Mon Oct 06, 2025 9:21 pm Any other pedals you would recommend

Here are my two boards for Jerry and Trey as of now so can wholeheartedly recommend any of these!

The Jerry wah is a 60’s Colorsound and Trey’s wah is a Teese…the MXR Phase 90 is a script reissue with an Analogman mod.