Mach1 gain MOD

[johnk_10]

I built the Mach 1 and it does sound very nice and transparent but IMO, it doesn't have anywhere near as much OD/Distortion with the gain cranked as the online demos show. Does anyone have ideas as to why?

 

[spi]

Which demos? A lot of those are probably using an amp on the edge and using Mach 1 to push it over (i.e. getting gain from the amp by boosting with the mach 1).

It's not a high gain drive. Do you have a clip of what you're getting?

 

[johnk_10]

i know it's not a high gain drive but i expected to get a bit more than the very mild gain that it has at maximum drive.

 

[johnk_10]

Which demos? A lot of those are probably using an amp on the edge and using Mach 1 to push it over (i.e. getting gain from the amp by boosting with the mach 1).

It's not a high gain drive. Do you have a clip of what you're getting?

i'm using it with a bass, but no soundclip yet.

 

[BuddytheReow]

That’s your issue. The pedal is tuned for guitar, not bass. There are better bass OD pedals out there. You might want to look up Chuck Bones bass klon for low end OD territory.

 

[johnk_10]

i have about 1000 pedals at the moment and made my own Bass Klon years ago. IMO, the lightspeed is a great low gainer for bass.

 

[Feral Feline]

Let's clarify that, you have built (or have built and sold a few of) those 1,000 pedals.
I'm catching up, but probably will take me a few life-times.

I have no idea why the circuit as traced doesn't match up with online demos, but...
Have you tried changing the A500k DRIVE to an A1M pot for the DRIVE?

 

[johnk_10]

Let's clarify that, you have built (or have built and sold a few of) those 1,000 pedals.
I'm catching up, but probably will take me a few life-times.

I have no idea why the circuit as traced doesn't match up with online demos, but...
Have you tried changing the A500k DRIVE to an A1M pot for the DRIVE?

about 1/2 of the 1,000 pedals that i have i built, and the others are the factory originals..

yes, that's the first thing that did, changing the A500K drive pot to a A1M, but, surprisingly it didn't change it much.

 

[phi1]

Hey I remember seeing your posts on the tagboard site way back in the day. Inspiring stuff.

Check out the Tommy switch for more gain. To do similar on the Mach 1, reduce R11.

The catch is, for the same frequency response; you need to scale the other components (scale R12 the same percent as R11, scale C5 & C6 inversely). So if you cut the value of R11 by 25%, you’d have to multiply the cap values by 4.

 

[szukalski]

Hey John, here's the schematic for my implementation of Chuck's gain mod recommendation:

It's still going to be a mid-range OD, but you'll get a bit more ooomph out of it. If you want more gain, then a Vemuram Karen or Butter Machine may be more interesting. Both "suffer" from low end and they could be better for bass.

 

[johnk_10]

thanks guys. i think that i'm going to leave it as is since it does already sound great with a bass (very little low end loss if any).