The Old Blood Noise Endeavors Blackcap is a dual tremolo pedal that puts two different kinds of tremolo in one box: a simple three-knob analog tremolo and a more complex digital tremolo. The analog side is a traditional volume-modulating tremolo, the kind of effect most players know from classic tremolo circuits. The digital side is a harmonic tremolo, which crossfades between highs and lows to create a unique modulation rather than simply dipping the whole signal in volume1.
An analog tremolo and a harmonic tremolo in one box
The two tremolos are not just stacked one after the other. Old Blood Noise Endeavors says they can be routed in parallel or in series, or isolated one at a time, so the Blackcap can act as a straightforward analog tremolo, a standalone harmonic tremolo, or both together1. A series/parallel toggle sets whether the analog tremolo runs into the digital one or both work side by side1.
The Blackcap is a sibling to the Whitecap, the company's dual asynchronous tremolo. Old Blood Noise Endeavors describes the Blackcap as the harmonic variation of that pedal1, so the difference between the two comes down to what the digital side does: on the Blackcap it is a harmonic tremolo that splits and crossfades the highs and lows, in the manner players associate with old amp-style harmonic tremolo circuits. For more on the wider effect family, see the site's page on Tremolo Pedals.
MusicRadar's reviewer Trevor Curwen, writing about the pedal, noted its price at £2092.
The controls, tap tempo and routing
The two tremolos have separate control sets:
| Tremolo | Controls |
|---|---|
| Analog tremolo | Rate, Depth, Volume1 |
| Digital tremolo | Rate, Depth, Volume, Tap Tempo, five selectable waveforms1 |
The analog side keeps things to the three knobs a traditional tremolo needs. The digital side adds a Tap Tempo switch and five selectable waveforms, and it also has ramping: holding down the Tap Tempo switch speeds up or slows down the digital tremolo, which lets a player bend the rate during a part rather than jumping between fixed speeds1.
For syncing to outside tempo, there is an external tap tempo jack1.
Power and bypass
The Blackcap requires a 9V DC center negative power supply with a 2.1mm jack, capable of 110mA, and no supply is included in the box1.
There is no battery option, and at 110mA the Blackcap draws more current than some daisy-chain or low-output power supply outputs provide, so it needs its own supply capable of that draw1.
Bypass is true bypass, handled by a soft-touch footswitch that Old Blood Noise Endeavors says keeps switch noise minimal1.
Availability
The Blackcap is listed as Sold Out on Old Blood Noise Endeavors' product page as of 25 October 20261. The enclosure art is by Jeffrey Alan Love1, and the maker points players to the Blackcap manual on its site for full operating details1.
Videos
Old Blood Noise Endeavors
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Tanner Cundy
Questions
Is the Blackcap true bypass?
Yes. The Blackcap uses a soft-touch bypass footswitch that Old Blood Noise Endeavors describes as true bypass, with minimal switch noise. When the pedal is bypassed, your guitar signal passes through without the tremolo circuitry in the path.
Does the Blackcap take a battery?
No. The Blackcap has no battery option. It requires a 9V DC center negative power supply with a 2.1mm jack, capable of supplying 110mA, and the power supply is not included with the pedal.
What power supply does the Blackcap need?
Old Blood Noise Endeavors specifies a 9V DC center negative power supply with a 2.1mm jack, capable of at least 110mA. The supply is not included, so make sure your pedalboard power source has a spare output rated for that current draw.
What is the difference between the Blackcap and the Whitecap?
The Blackcap is the harmonic variation of the Whitecap, which Old Blood Noise Endeavors describes as its dual asynchronous tremolo. Both combine two tremolos in one box, but the Blackcap's digital side is a harmonic tremolo that crossfades between highs and lows, while the Whitecap is the dual asynchronous design.
Is the Old Blood Noise Blackcap discontinued?
The Blackcap is listed as Sold Out on Old Blood Noise Endeavors' own product page as of October 2026. That means the maker currently has no stock, though the page does not state whether the pedal has been permanently discontinued.
Sources (2)
- Old Blood Noise Endeavors, Old Blood Noise Endeavors
- Walrus Audio Monumental Harmonic Stereo Tremolo review, MusicRadar, 2024-09-23
