Pedals that stack with the Peavey Rock Master Preamp

Xotic EP Booster

Stack Xotic EP Booster on top and a high gain tone tightens toward clean boost

Keeley Red Dirt Overdrive

Keeley Red Dirt Overdrive takes that high gain character and pushes it toward mid-forward

Electro-Harmonix Deluxe Electric Mistress

Keep Electro-Harmonix Deluxe Electric Mistress after Peavey Rock Master Preamp in the signal chain, clear of Peavey Rock Master Preamp's own gain stage

DryBell Unit67 Compressor

DryBell Unit67 Compressor's own compressed character is the real reason this is worth trying

Hungry Robot Moby Dick V2

Keep Hungry Robot Moby Dick V2 after Peavey Rock Master Preamp in the signal chain, clear of Peavey Rock Master Preamp's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

Walrus Audio Fathom

Keep Peavey Rock Master Preamp's high gain voice out front: Walrus Audio Fathom goes after Peavey Rock Master Preamp in the signal chain so its ambient voice doesn't muddy it — goes in the amp's FX loop (or last, into a clean amp)