Keeley Hydra Stereo Reverb and Tremolo Pedal

Pick up a Hydra to drench your guitar tone in the dense sound of stereo effects. Choose from three different reverb and tremolo styles to color your sound.

The HYDRA combines high-fidelity Reverb and Tremolo to add space and dimension to your guitar, bass, or keyboard signal. After the team at Keeley completed the ECCOS, we wanted to craft the perfect companion pedal, and we did just that with our new, feature-rich blue box.

Bathe your sound in Spring, Plate or Room Reverb, then add tap-tempo enabled Harmonic, Vibrato, or Sine Wave Tremolo with the press of a button. You can easily change the order of effects or the character of the Tremolo or Reverb with the HYDRAs smart Alt Controls. You can even create an Infinite Hold Reverb Trail!
Save up to three presets with ease using our intuitive save feature. Engage Reverb Trails on the fly, no more internal dip switches. The Hydra can be used with pro remote switching systems and offers both TRS Expression Pedal and External Tap-Tempo inputs.

The HYDRA is a complete end-of-pedalboard solution that fits perfectly in any musicians rig, regardless of genre. Experience next-level processing power in this pedalboard-friendly enclosure. The sky, or more appropriately, the ocean floor, is the limit with the new Keeley Electronics HYDRA!


- Stereo high-fidelity Reverb and Tremolo effect pedal
- Dreamy and accurate sounding Spring, Plate, and Room Reverbs
- Vintage-voiced Harmonic, Vibrato, and Sine Tremolo
- 3 Preset locations
- On board or Remote Tap-Tempo
- Smart Alt Controls for Shimmer, Spring Age, Room/Hall Size
- Infinite Hold for Reverb trails
- Expression pedal can be assigned read more to any knob
- Effect Order, Reverb or Tremolo first, switchable on the fly
- True-Bypass or Trails switchable on the fly
- 9 Volt DC, 146mA ultra low-current design
- Made in USA
WARNING: Cancer and Reproductive Harm -
read less

Dimensions and Weight in Packaging
Base Item
Shipping Weight: 1 lbs
Shipping Dimensions: 6 x 4 x 3 in
Manufacturer Part Number (MPN): KHydra

For support or warranty questions, please contact the manufacturer:
Phone: 405-341-2025

Reviewers gave this product an overall rating of 5 out of 5 stars. (1 ratings)
Submitted March 12, 2024 by Allan B

"Great workhorse pedal"

Overall: 5 out of 5 stars
(see rating details)
Verified Customer zZounds has verified that this reviewer made a purchase from us.
The reverbs are fairly standard and go from drippy 60's spy movie to a huge hall. There are some modulation and modification parameters but nothing in the territory of the huge cloud P&W style reverbs, but that's not where I think this pedal is aimed anyway. However when ran in stereo it can still produce some really beautiful ambience, especially when paired with Keeley's Halo delay. Definitely a step or two above most amps built in digital reverbs, and you can have 3 reverb presets plus the panel. The tremolo is also very nice and can go from subtle to How Soon is Now. It's not quite as crazy as some trems out there, but all modes are very musical. You can also have 3 trem presets plus panel. It also sounds wonderful in stereo.For performance features it takes a tiny bit of tap dancing to move presets or engage tap tempo, and even though it's the same layout it requires different steps (pun intended) to navigate than the Halo which is confusing at first. There is also an expression pedal jack, but I've not used it yet.When you take into account all this pedal can do, plus it's stereo AND normal form factor, it's a bargain. Definitely check it out if you are in the market.

Musical Background:

Playing for decades and still out playing covers that are older than me :)

Musical Style:

Rock, prog, CCM
Did you find this review helpful?
Thanks for your opinion!


FREE -Day Shipping!
Get it  for
Get it by if you order within
Shipping to