Grateful Dead Music Forum

A place to talk about the music of the Grateful Dead 

 #126699  by williamsaut
 Sat Apr 13, 2013 6:25 pm
Hey guys, I pulled out a Sarno Dirt box and tried it out again at practice the other night and you know, it sounds fantastic. At first I didn't think it sounded up to snuff to the MXR script Dist+ I had been using when I first bought it. Then I took the MXR out of the chain and replaced it with an Earth drive which I'd been using for a while now but found that it didn't get dirty enough. Then low and behold the dirt box. I just dimed the drive knob and brought up the volume to match overall volume and man it sounds great. The little switch with the ovals for 'fat' or 'tall' each have a distinctive tone and both are very musical.

Anyone else put some time in with one of these pedals? My enthusiasm for this pedal has been reborn.

 #126700  by Smolder
 Sat Apr 13, 2013 6:28 pm
I use the earth drive for clean mode at lower volume as it adds just enough edge... use a variety of other pedals to get dirt... tube screamer, KOT if I want compressed, or an old SD-1. Have not tried the script or the dirt box.
 #126710  by SarnoMusicSolutions
 Sun Apr 14, 2013 9:06 am
Cool... glad you like it.

The Dirt Box was my first pedal. I only made 50 of them, so they're fairly rare. Maybe I made 100, can't remember exactly now.

The circuit of the Dirt Box is very much in the family with the MXR+, but it's more vintage than that. It's actually inspired by the old Jordan Boss Tone and with some fidelity and voicing tweaks. The idea here is that it pre-dates opamps, so instead of an opamp like the MXR, it has a pair of silicon transistors set up in a gain/clipping circuit sort of like a Fuzz Face but run cleaner with more headroom. Then after that stage we have the pair of clipping diodes just like the MXR+. People say that this circuit is the one that inspired the MXR+ and the others that use that general topology. The Dirt Box has a different sound from the MXR+ because the transistors also clip a bit. In the end you get kind of a clean-ish, silicon fuzz face barely clipping and then the MXR+ harmonic content which is the dominant distortion factor. So it really does behave a bit like the MXR+.

The toggle switch that shows a fat and a skinny "O" designates the hi-pass filter. The skinny "O" has less low bass and the wide "O" means there's more bass. That bass content has a big effect on the harmonic content.