GREER AMPS: Lightspeed X Southland Overdrive, Switch Mod

So given the Lightspeed and Southland are basically the same circuit, I thought I might add a switch to swap between the two.

The switch does three things;

• Switches the hard clipping diodes in/out

• Changes op-amp gain (to account for the hard clipping diodes)

• Changes Drive pot resistance

While they use different op-amps, they're both just dual op-amps, so choose a favourite and run with it.  The Lightspeed uses an expensive high-performance op amp, and the Southland uses a standard TL072.

Schematics for both can be found over at PedalPCB, if you want to check out the similarities yourself.   

It's a little cramped now, but you can always add a row on the right-hand side to free up some space.

LIGHTSPEED X SOUTHLAND OVERDRIVE SWITCH MOD

NOTE:  I've not tested this on the breadboard or LTspice, so I can't tell you if there are significant output level differences between the switch settings - I don't know if it would be a good idea to have the switch as a foot switch.  It might be awesome; I just don't know...  

GREER AMPS: Soma 63 Vintage Preamp

The Soma 63 is an amp in a box style pedal, with the usual array of J201s with trimmers replacing valves, an amp-style tone stack, and a transformer at the end of the signal chain thrown in for good measure.  

I added some mounting points on this, as you don't want a board with a transformer on it floating around inside an enclosure - just be careful with traces around the mounting points, depending on your preferred mounting type. 

GREER AMPS SOMA 63 VINTAGE PREAMP - VERO LAYOUT

GREER AMPS SOME 63 PREAMP - VIDEO DEMO

GREER AMPS: Southland Harmonic Overdrive

Greer Amps have taken the Lightspeed overdrive and have made a few mods to give us the Southland Harmonic Overdrive. 

• added a set of hard clippers after the first gain stage
• boosted the gain of the output to make up for the BAT41 hard clippers
• increase the drive pot value

Could try germanium diodes instead of the BATs, but it will probably sound about the same.  

GREER AMPS SOUTHLAND HARMONIC OVERDRIVE - VERO LAYOUT

GREER AMPS SOUTHLAND HARMONIC OVERDRIVE - VIDEO DEMO

GREER AMPS: Tomahawk Deluxe Drive

This is a simple one from Greer Amps - the Tomahawk Deluxe Drive.  It has some distinct similarities to a Rat or Distortion +, in that there's opamp clipping, driving hard clipping diodes, and a tone control. 

Schematic from PedalPCB.   I added a buffer on vref, as half the opamp wasn't being used, so why not.

GREER AMPS TOMAHAWK DELUXE DRIVE - VERO LAYOUT

GREER AMPS TOMAHAWK DELUXE DRIVE - VIDEO DEMO

GREER AMPS: Lightspeed Organic Overdrive

GREER AMPS LIGHTSPEED OVERDRIVE - VERO LAYOUT

note:  a standard TL072 can be used, the OPA is a "premium" dual op-amp.

GREER AMPS LIGHTSPEED OVERDRIVE - VIDEO DEMO