Asheville Music Tools ACV-1 Time Warping Chorus & Vibrato

The Analoger™ Series ACV-1 chorus/vibrato/slapback is the latest creation in our series of 100% analog effects. The ACV-1 consists of a modulated BBD delay line with a flexible supporting cast of synthesizer-inspired controls. On the surface, the ACV-1 is simply a highly tweakable classic chorus. In reality, it is a veritable powerhouse of time warping modulation effects: shimmering comb filter swirls, luscious true pitch vibrato, glitchy textures, ringing metallic pipe tones, and even a faux reverb.

This astounding analog modulator was engineered by Hawker to deliver the ultimate time warping experience. With a bit of a mind flip, you’ll be into the time slip—and nothing will ever be the same!

What makes the ACV-1 special?

At the heart of every chorus is a short delay whose time is modulated by a low frequency oscillator (LFO). The ACV-1 uses a 1024-stage X-Vive™ high-voltage MN3007 BBD chip for its delay line. Mixing that delay back in with the original signal produces the familiar, lush sound of chorused voices in unison.

Many choruses keep the delay time fixed, but our Time knob lets you warp through the decades of chorus. Start in the middle for a tight 70’s-style chorus. Go longer for a drippy 80’s chorus and a warm slap delay, or go shorter for flanging tones.

Another uncommon addition is our Feedback knob with phase options. This lets you deepen the chorus effect and explore more exotic metallic or vocal sounds. At high feedback settings you can use the Time knob to dial in peaks and notches for resonant sounds, like a pipe or a bell. The Tone control changes the frequency response of the feedback loop to make your chorus more shimmery, or more dark and haunting. Utilizing the phase switch you can produce hollow, deep vocal sounds akin to a talk box.

Our LFO includes multiple waveforms: triangle for classic chorus sounds, sine for gooey vibrato, and square wave for rhythmic glitches and pitch jumps. The Rate and Amount controls have a huge range from subtle dimension to complete time warping madness. Or you can zero out the LFO to explore double-tracking effects, static comb filtering, and short delay.

The Mix control has a range from fully off to 100% wet, which lets you dial in subtle sounds or go all-in for true analog pitch vibrato. These settings are great for Leslie organ sounds or tape-like warble. The Tone control is even more useful here, as a way to sculpt the overall tone of your wet signal.

Finally, the CV jack rewards more intrepid sonic explorers with an even wider range of control. Increase the feedback into self-oscillation, push the LFO beyond its limit to audio rates, or drop the delay time into a lo-fi, ring-modulated soundscape. 

With its thoroughly engineered set of features, the ACV-1 synthesizes decades of time warping modulation effects to inspire a whole new dimension of sounds.

Electrical Specifications:

• Type: 100% Analog signal and control path

• Bypass Footswitch: effect on/off user selectable True Bypass or JFET Buffered (Accessible by removing ACV-1 Cover)

• Power: 9VDC @ <150mA. 70-90mA typical. Up to 250mA start up. Standard pedal center negative 2.1mm x 5.5mm barrel.

• Delay Time:  3.1ms - 59ms. 1.9ms - 95ms with LFO and to 155ms with external CV

• Feedback: 0 to near infinite. Capable of self-oscillation using tone or EXP/CV input coupled with knob position.

• Rate: LFO RATE, from 0.1Hz to 14Hz (28Hz with CV control)

• Amount: LFO depth control from OFF to 60% of TIME sweep

• Mix: Center 50%. Adjust from full wet to full dry

• Tone: ~740Hz center tilt filter. Center = Flat to 0.3dB

  High +5dB to -10dB, Low +4dB to -7dB.

• Phase Switch: 180° phase shift of wet signal and feedback signal.

• LFO: Selectable Triangle, Sine or slewed Square wave

• Expression Switch: 4 position rotary selects Time, Feedback, Rate or Amount external control. All controls are additive to the front panel knob adding extended range. TRS jack usable with CV or Expression pedal, (CV range is 0-5V). Ring supplied current limited 5V output. Control input on Tip.

• Input impedance: >1MΩ

• Output impedance: 1KΩ Max (5k max for buffered bypass)

• Max input level: +14.25dBµ (4.0V RMS)

• Max output level: +14dBµ (3.9V RMS)

• Noise Reduction: 2:1 broadband with 10dB HF emphasis

Physical Specifications:

• Genuine Hammond™ die-cast aluminum enclosure,

• Dimensions: D=4.95” (12.5 cm), W=3.75” (9.4 cm), H=2.25” (5.8 cm)

• Weight: 15oz (425g)

 Note: All specifications subject to change at the whim of designer.