Walrus Audio ACS1 MkII

Walrus Audio updated their Amp/Cab Simulator ACS-1 with a MkII, after the original version’s 2.0 firmware introduced some new features.

Firmware 2.0 Changes
The firmware update, made public in August 2023, bring these improvements:

  • Improved dynamic range on the gain knob on the existing amp simulators to allow for extra breakup
  • The V1 cabinet IRs were replaced by new ones designed by David Hislop and Kenyon Reed at Tone Factor.

MkII Changes
The new model keeps all the features of the original, while adding:

  • 3 new amp model emulations, for a total of 6: Mesa Boogie Dual RectifierOrange Rockerverb and Peavey 5150 (emulating the amp’s red channel), joining the old ones (Fender Deluxe Reverb, Marshall Bluesbreaker and Vox AC30).
  • 6 new cabinet simulations, for a total of 12 (cab and amp models can be matched to taste).
  • Ability to upload custom IR files

Other features include Stereo in/out, extra Boost footswitch that gives you an extra Volume and Gain setting, a gate to control unwanted noise, and preset capabilities (3 in the box and 128 via UBS Midi).

Intriguingly, the two outputs can be configured either in Stereo with the same amp/cab setting or in Dual mode using a different amp/cabs simulation on each channel.

Room ambiance knob simulates the natural room reverb you get when you record an amp: with completely dry at zero (the way it sounds in an iso booth) and a large room reverb at maximum settings. The headphone output in the icing on the cake.

Check out the videos below and the manufacturer’s description at the bottom for extra info.

We added the Walrus Audio ACS1 MkII to our comprehensive article about the best amp modeling and cab sim pedals.

Walrus Audio ACS1 2.0

Walrus Audio ACS1

The [ACS1]™ is an amplifier and speaker cab simulator delivering the sound and feel of world-class amplifiers, complimentary speaker cabinets, and controllable room size. With the ASC1, players have expansive options to deliver their tone whether it’s on stage, in the studio, or practicing at home. Simple controls, stereo in and out, onboard presets, and MIDI support make the ASC1 an immeasurable tool in a guitarists arsenal.
Amplifiers
The ACS1 models three vintage amp styles crucial to music industry history designated by their places of origin. When running the ACS1 in stereo, one amp can be used through both channels or mix and match amps and cabinets on the left and right channels with the L + R switch. Simply choose the channel you want it to modify, select your amp and cab model, and set your levels. Then flip over to the other channel and choose your amp and cab settings. If you would like to use the same settings on both channels, set the switch to the middle or “+” and dial in all your settings. They will be duplicated on the left and right outputs.   
Volume and Gain work together, similar to how they would on an amp. For example, increasing gain levels will also raise overall volume output so adjust the volume knob accordingly. 
Fullerton is inspired by the classically bright and clear Fender® Deluxe Reverb®. Crisp clean tones with loads of headroom that players have come to love over the years.
London is inspired by a 1962 Marshall® Bluesbreaker® with a harmonically rich, valve-driven breakup. Articulate and sensitive response.
Dartford is inspired by the legendary jangly high-end tones from a 1960s Vox® AC30 with all the bite and chime from the British Invasion.
Cabinet IRs
The ACS1 holds six high-quality cabinet impulse responses (IRs). It ships pre-loaded with six custom cabinet IRs developed by Walrus Audio that sound great with each amp. Users also have the option to load their own IRs via our new customer web app found at walrusaudio.io.
Use the ABC Cab toggle switch to select your cab preference. Access the second set of cabs by holding down bypass while changing the cab toggle position.
Room Ambience
Simulate the size of the room that your amp and cabinet are in. At zero, it would resemble tracking your amp in an isolated environment with no reverb. At max would emulate a natural-sounding, large studio environment.
Presets
Save up to three presets onboard by dialing in your favorite sound then pressing and holding the bypass and boost switch simultaneously. Both LEDs will flash confirming your settings were saved. Cycle through presets by pressing and releasing bypass and boost simultaneously. The pedal will cycle through the three onboard presets – red, green, and blue. When power is removed from the pedal, it will boot up in the last used preset. Using MIDI, up to 128 presets can be saved and recalled.
Boost
A boost feature is available by pressing the boost switch. It allows you to quickly jump to a preset level of volume and/or gain. The boost LED will flash letting you know that it is active. To set the boost, simply click the switch on and adjust the volume and gain knobs to taste. Pressing the boost switch again will save your boost settings and return the pedal to its normal level of volume and gain.