The Greyscale Devices Echo Machine+ is an echo/delay pedal that does something most delay pedals do not: two delay sounds combine together to form one signal, so you can run a short bright repeat and a longer darker repeat at the same time. Pedal of the Day's reviewer, Mike B, described the result as "a unique, spacey, trippy, echo/delay sound." The pedal also carries a built-in preamp with its own Volume control, and it offers an expression pedal output and true bypass switching1.
Controls
The Echo Machine+ keeps its front panel simple: four knobs and two switches, each with a distinct job.
| Control | What it does |
|---|---|
| Echo | One bright repeat; the reviewer found it works great for chick'n pick'n licks and short slapbacks1 |
| Dwell | Produces a darker tone, with more repeats added1 |
| Time | Delay time, to around 500 to 600ms at maximum1 |
| Length (switch) | Halves the range of the Time control1 |
| Volume | Controls the amount of boost from the preamp1 |
| Bright (switch) | Adds presence to the preamp1 |
The two voices divide the work between them. The Echo knob gives you the single bright repeat for slapback territory, while the Dwell knob stacks up darker repeats for the longer, spaceier side of the pedal. Because both combine into one signal, the two can sit on top of each other rather than replacing one another1.
The Length switch is the control players are most likely to ask about: it halves the range of the Time control, which tightens the sweep of the knob and makes short delay times easier to dial in precisely1.
Power and bypass
The pedal runs from a standard Boss-style 9V jack, so it fits the center-negative 9V DC supply most players already have on their board. The review does not mention battery operation, so treat a DC adapter as the expected power source. Bypass is true bypass switching, and there is an expression pedal output for foot control of the effect1.
The Echo Machine+ is housed in what the reviewer called "A nice, big, silver metal box," so leave room for it on your board1.
What reviewers said
Pedal of the Day's verdict leaned on usability as much as sound. Mike B wrote that "it's as simple and fun to use as any other pedal you'll come across," which is high praise for a pedal that runs two delay voices at once1.
Echo Machine+ and other Echo Machines
The name Echo Machine has been used by several other makers, and the circuits are not related. If you are comparing, here is how they differ:
| Pedal | What it is | Delay time |
|---|---|---|
| Greyscale Devices Echo Machine+ | Two delay voices combined into one signal, with preamp1 | Around 500 to 600ms max1 |
| Drunk Beaver EM-1 Echo Machine | Emulation of the Ibanez EM-5 with added tone control; controls are Tone, Feedback / Repeats, Delay Level and Delay Time2 | 50ms to 600ms2 |
| Drunk Beaver Vinnytsia Echo Machine | Evolved take on the Ibanez EM-5 with added tap tempo3 | 40ms to 700ms3 |
| Asheville Guitar Pedals Echo Machine Delay | Digital delay pedal4 | Up to 400 milliseconds4 |
| GOKKO Magrane'Echo Machine | Analog delay with true bypass5 | Not stated |
For more on the effect type itself, see the site's page on Delay Pedals.
Questions
Is the Greyscale Devices Echo Machine+ true bypass?
Yes. Pedal of the Day's review lists the Echo Machine+ as having true bypass switching, so when the pedal is off your guitar's signal passes through without the delay circuit loading it down.
Does the Echo Machine+ have an expression input?
Yes. The review on Pedal of the Day notes an expression pedal output, which lets you control the pedal's delay from your feet while you keep both hands on the guitar.
What power supply does the Echo Machine+ use?
The Echo Machine+ takes a standard Boss-style 9V jack, so it runs from the same center-negative 9V DC supply most pedalboards already use. The review does not mention battery operation, so plan on a DC adapter.
How long can the Echo Machine+ delay time go?
Pedal of the Day puts the Time knob's maximum at around 500 to 600 milliseconds of delay. The Length switch halves the range of the Time control for shorter, tighter settings.
What does the Length switch do on the Echo Machine+?
The Length switch halves the range of the Time control, according to Pedal of the Day's review. That gives you finer control over short delay times, which is where slapback and country-style echoes live.
Sources (5)
- Greyscale Devices Echo Machine+ Delay, Pedal of the Day, 2014-08-16
- Guitar Pedal X, Guitar Pedal X, 2025-08-08
- Guitar Pedal X, Guitar Pedal X, 2024-07-12
- Asheville Guitar Pedals Echo Machine Delay, Pedal of the Day, 2024-04-20
- MAGRANE’ECHO MACHINE, GOKKO AUDIO (gokkoaudio.com)
