Review: Electro-Harmonix Oceans Abyss Advanced Reverb Laboratory

Building upon the current lineup of reverb pedals from Electro-Harmonix, which has long revolved around the beloved Holy Grail, the Oceans line of stompboxes have gathered much momentum among ambience enthusiasts in recent years.

While the Holy Grail, which isn’t going anywhere, holds up great for such an early digital unit, the Oceans pedals have been tailored to expand upon the template laid out by the classic. This range essentially offers more options for players who need extra variety from their Reverb effects unit.

Oceans Abyss stands as the flagship model in the Oceans line, updating Electro Harmonix’s (EHX) highly acclaimed reverb algorithm to deliver an advanced workstation that is designed to provide truly immersive effects. 

For a unit with such impressive capabilities under the hood, I must say that EHX have gone above and beyond to make the Oceans Abyss not only presentable but also inviting. No potentially intimidating UI here, the Oceans Abyss looks not dissimilar to some other dual-stomp effects units that many of us would have used over the years.

Each side of the Ocean’s Abyss mirrors the other in terms of control layout and switch position, with the centre of the unit featuring a nice, easy-to-read OLED display and buttons to store and access presets. A third footswitch is located in the centre of the unit for switching modulation fx in and out of the assigned patch. 

Controls on the faceplate of the EHX Oceans Abyss are also relatively straightforward, with each side of the unit boasting pots for panning— the Oceans Abyss can run stereo— as well as pre-delay and time. Three sliders serve to control the blend on the units’ panning pot, and a two-band equaliser provides the means to sculpt the frequency response of your verb.

Getting started with the Oceans Abyss is quick and easy. I simply pressed the Home button to display the Signal Path View, which is commonly referred to as the Home screen in EHX documentation. From here, selecting a preset was as easy as hitting the Preset button, which will illuminate it.

One thing I really like about this new unit is EHX’s special NavCoder navigation control. Pushing the NavCoder directionally will move the cursor on the OLED towards your desired preset or the parameter that you wish to tweak. Subsequently, rotating the NavCoder allows you to adjust the value of specific parameters, similar to how one would utilise a pot on a traditional pedal or amplifier. For hands-free operation, the simultaneous pressing of A+EFFECT or EFFECT+B footswitches allows the user to navigate the preset menus in much the same way.

Another feature of the Oceans Abyss that I really appreciated was the system’s Live Mode, which essentially lets you engage with the pedal’s analogue controls much like a traditional reverb or delay unit. To exit a preset and enter the unit’s Live mode is as simple as pressing the Preset button to bypass the chosen preset. Additionally, saving a user-made preset is as easy as holding the Preset button and inputting the relevant information, such as preset name and slot, via the NavCoder. 

This is just the tip of the iceberg when it comes to the functionality of the Oceans Abyss, however the fact that I managed to get up and running with the unit in a matter of minutes goes to show just how much thought EHX has put in when it comes to making this unit intuitive and user friendly. 

This brings me to the sounds. 

The Oceans Abyss revolves around two reverb engines that feature independently programmable stereo algorithms. This means that the Oceans Abyss is essentially two individual pedals in one, which is a dream for players who are already stacking ambience effects together to achieve their tones. 

Hall, Shimmer and Spring algorithms are all familiar yet luscious; however, there is a plethora of others to choose from for those seeking other sounds. This works to make the Oceans Abyss an extremely versatile unit, but there’s way more going on here than traditional reverb sounds.

The Oceans Abyss’ success in innovating via the incorporation of customisable FX Blocks. These include the standard culprits such as modulation and time effects like delay, chorus and tremolo, but also some more wildcard entries like Bitcrusher.

Eight blocks are available within a customisable signal chain, all accessible and easily viewed via the unit’s high-quality OLED display. I think that anyone who is familiar with a block interface, such as the ones implemented by companies like Fractal, will find little difficulty in effectively accessing and tweaking parameters within their desired digital signal chain.

Possibilities are endless when it comes to the EHX Oceans Abyss, whatever you want is at your fingertips, whether it be a simple spring reverb or a fully fledged Shoegaze dreamscape complete with stereo hall and spring reverbs, overdrive, tremolo and chorus. The Oceans Abyss really has the potential to be a total solution for anyone who is looking for a single unit solution to all their time, ambient and modulation-based needs. 

All this, combined with fully stereo I/O with integrated FX Loop, plus MIDI IN and OUT ports with MIDI IN support of PC, CC and tempo clock, only serves to further expand the immense talents of the Oceans Abyss. In 2025, the Electro Harmonix Oceans Abyss is a must for anyone in the market for a professional-grade reverberation unit that will make even your wildest ideas become a reality. 

For local Electro-Harmonix enquiries, keep reading at Vibe Music.