The Sinkhole is perhaps our most ethereal reverb unit to date. We’ve combined a harmonically-rich “hole” reverb with an impossibly deep four-voice chorus that’s been outfitted with a feedback control and a gentle high-cut filter. Within this arrangement, the feedback control allows the Sinkhole to reach deep within the reverb to extract some truly otherworldly tunable modulation, featuring everything from comb filtering to pseudo-phaser to haunting auto-filtering. That aspect never gets out of control; it’s all wrapped up within the confines of the reverb. We’ve stretched the reverb trails out to their absolute limit, with the maximum decay time almost freezing your signal in space. Extreme settings evoke warm synthesizer pads, reminiscent of vintage analog-digital hybrids, holding your modulated note indefinitely. Combine all that with a full wet-dry blend and a warm preamp circuit, and you’re beginning to feel the gravity of the Sinkhole. Let’s get pulled in, shall we? FDBCK: This control has a dual function; in addition to adjusting the amount of feedback in the chorus circuit, it also controls the depth of the chorus. There’s a lot going on within this one knob both in terms of individual function and interactivity, and different settings yield much more varied results than normal. It invites you to step into the hole and shut the door behind you.MIX: This is your standard wet-dry blend; all the way down is your clean signal run through the Sinkhole’s onboard preamp, and all the way up is all reverb, all the time.MOD: This controls the rate of the chorus modulation. Setting this control to the minimum slows the LFO down to a barely-discernible rate. Increase for a more dramatic effect. VERB: This adjusts the decay time of the reverberated signal. Turning this up to the maximum gives you near infinite sustain.VOL: Adjusts the gain of the onboard preamp. You can use this as a fine clean boost with or without the reverb, if you wish. At very high settings, your particular combination of guitar and other pedals may cause the preamp to slightly clip. If you run the Sinkhole at 18v, this is not an issue.TRUE BYPASS/BUFFER SWITCH: This switch is internal and requires removing the backplate to access. Do you want your reverb trails chopped off the second you switch the Sinkhole off, or do you want them to continue ringing out even after the pedal is disengaged? For the former, select true bypass (T.B.). For the latter, buffered (BUFF.) mode. The unit ships as stock with buffered mode selected. FACTS AND FIGURES Fact: You will enjoy the Sinkhole.Fact: This pedal accepts a center-negative (the standard) power supply, between 9 and 18 volts DC, and with at least 100mA of current. You can exceed 100mA and it will be fine. Do not give the Sinkhole reverse-polarity (center positive) or AC supplies.Bonus fact: if you give the Sinkhole AC or a center-positive supply, you will void the warranty. Bad move.Figure: The input impedance of the Sinkhole is 160K ohms.Figure: The output impedance of the Sinkhole is 18.4K ohms.
