The Drunk Beaver Heavy Bat is the "ultimate Rat-style pedal" (at least according to Stefan Karlsson of the Guitar Pedal X blog), who says that the Heavy Bat is "probably my favourite ever Rat to date - even against something as excellent as JHS Pedal’s PackRat."
The Heavy Bat takes the guts of the Bat and Bat Cold War and adds tons of additional switching and modifications for what must be one of the most complete pedals in this genre - ever!
Heavy Bat EQ
Key to its flexibility is the switchable EQ section, which allows you to choose either the "Classic" one-knob Filter control of the Rat, or "Heavy" to activate a Boss Heavy Metal HM-2-style 3-band tone stack consisting of Low, Mid and High controls.
Heavy Bat Clipping Modes
The Heavy Bat has 8 clipping modes, independent for each channel:
"LED" - 2 red LEDs
"None" - raw op-amp clipping
"Si" - silicon 1N914 as used in the original Rat
"Soviet Si" - silicon KD541A
"Hybrid" - germanium and silicon diodes in combination
"MOSFET" - BS170 transistors
"Ge" - NOS Soviet D9 germanium diodes (asymmetric)
"BAT" - BAT85 Schottky diodes
Heavy Bat Op-Amp Modes
The Heavy Bat has a rotary switch to select from 4 different op-amp chips (twice as many as the Bat and Bat Cold War!):
"Classic" - a NOS LM308 as found in the original Rat)
"Soviet" - a UD1408B (Soviet LM308 clone as used in the Bat Cold War)
"Modern" - a Motorola TYA34083 (similar to the chip used in the Wampler Ratsbane)
"Ancient" - a NOS Czech KA741, a variation on the LM741 used in early distortion pedals such as the MXR Distortion+
Heavy Bat Controls
As well as the various Clipping and Op-Amp modes, the Drunk Beaver Heavy Bat features per-channel Volume controls, a Distortion control and a Blend control which is especially useful for retaining some of your clean signal when playing bass or down-tuned riffing.
The dual-footswitch design allows you to switch between two diode settings on-the-fly.
Heavy Bat Demo
Heavy Bat Features
Ultimate dual footswitch Rat design featuring NOS components
Handmade in Poland
Select from classic or HM-2 EQ sections
8 Diode Modes, selectable per channel
4 Op-Amp Modes
LED brightness trimmers: PCB trimmers allow you to adjust the status LED brightness for each channel