EBS – bass goliaths based in Bromma, Sweden – have a solid and proven record in the world of modern high-quality bass equipment for the stage, studio and school alike, be it amplification, speakers, accessories, and effects pedals, two of which we are looking at in this review. EBS has kindly sent us the latest “Revision 2” of their Studio Edition UniChorus and a 24bit digital high-resolution stereo reverb pedal, the DynaVerb Limited Spring Edition.

As usual, I repeat myself: I urge you to go grab some big earphones or quality speakers to listen to these reviews on. Laptops and mobile device speakers just won’t cut it with solo bass reviews! These devices carry no low-end depth!

Both pedals were released in June 2023 and have been enjoying success, not just in the bass world; these studio-quality devices are just as comfortable being used for guitar and other instruments, like synths. Both models are built for the road, featuring all-metal shells with recessed knobs. The switches are short-shaft types, meaning they are less likely to get knocked and, completing the exterior, metal sockets and soft-operation, heavy-duty foot switches.


First up for a closer look, the new UniChorus is a re-release of the original 1997 model by the same name. Updates to the pedal include more signal headroom, lower signal-to-noise, and a new switch design that sends the signal through a relay, rather than the physical foot switch, for lower noise and greater reliability. EBS have shaved some weight off the pedal, too, and, like the DynaVerb, a new coat of eye-catching livery!

EBS UniChorus

** Jeff Berlin, Legendary bassist adds his endorsement for the UniChorus for good reason.

Utilising analogue processing technology, as described by EBS, the UniChorus delivers a very clean, pristine modulation effect. The overall sound of my bass, which I selected specifically for these reviews, is articulate and very clear. I wanted to demonstrate how the EBS Studio Edition pedals allow my bass tone to remain intact, even with settings that could be considered over-saturated for bassists to use in a live environment.

Thankfully, getting a sound out of any EBS pedal is easy. The controls for the UniChorus are child’s play simple and, if you have used a guitar pedal before, then there will be no unnecessary scares. Modulation effects provide movement to your sound, at times a doubling effect and, in stereo, a breadth that moves across the stereo image when both outputs are utilised. The depth of the modulation is controlled by, yes, you guessed it, the Depth knob, and on the right-hand side, the Rate knob controls the speed of the effect.

UniChorus isn’t just one effect, though; oh, no. Yes, Chorus is catered for, but we also can enjoy Flanger and Pitch Shifting modulation, too. The former of the two, like the Chorus, is a well-balanced effect that does a great job of leaving your low-end fundamentals intact (ideal for bassists!!). But, on the same token, the Flanger, for example, isn’t as pronounced as some “Jet Engine” style devices. On the other hand, I enjoyed flicking into position two on the Mode switch for some lush pitch modulation. Go easy though: lower depth settings are rich and reminiscent of thick ‘80s bass tones; advancing the knob delivers more intense pitch-shifting that can make the bass sound a little drunk! Check out my pseudo-fretless sounds in my video!

EBS UniChorus

Inputs and outputs come care of solid 1/4″ jack sockets – you’ll notice, just like the original UniChorus, this modulation pedal is also stereo. Okay, okay, I hear the voices from some quarters screaming that bass is a mono instrument, and, yes, sure to an extent I agree with you. However, UniChorus can be used in mono, don’t fret! I have, for the benefit of your aural pleasure, recorded my entire video in stereo. Again, big earphones and you’ll have notes swirling around your ears in spatial nirvana!

If, however, it’s all a bit too much, the EBS UniChorus pedal is equipped with an effect mix trimmer located on the printed circuit board, which is easily accessible by removing the bottom plate. The factory setting is a 50% blend and you have ample adjustment for more or less intense effects.


The DynaVerb is a marvel of modern technology. Once upon a time (not that long ago actually, when I first started playing bass), we’d needed a whole 19” rack unit to accommodate the DSP power that we see in DynaVerb. 24bit processing at 48kHz offers supremely high-resolution audio for pristine and realistic spatial effects. Good news for musicians travelling light!

On board, we are treated to three main effect groups via the upper toggle switch, and three more modes of operation for each effect group with the lower switch. The “intensity” of the effect is dialled in using the left-hand Reverb knob, and if a darker reverb tail is what your sound calls for, progress the Tone control anti-clockwise to adjust the overall “hardness” of the space the effect is emulating.

EBS DynaVerb Pedals

Understandably, with so many parameters, my videos can end up being a bit longer, so I haven’t covered every option, though I’m not going to shortchange you! My reviews are about the details!

DynaVerb Limited Spring Edition dishes up three Hall reverbs from a 1.5s small space, to seven seconds of deep and rich cathedral spaciousness. With the type switch in the centre (“RM”) position, there’s a realistic “room” setting for adding “live studio” ambiences to DI’d bass – if you are using impulse responses that may sound a little on the dry side and need a bit of life to them. Type position “Other” contains the “special effects:” Gated reverb for those ‘80s synth-pop drum sounds, a gentle Reverse reverb effect for a bit of psychedelia, and, as the pedal name suggests, we have an articulate Spring reverb onboard. Like all of the effects on the pedal, full stereo output adds width to your sound and lifts harmonics and percussion to life.

On the subject of stereo, DynaVerb has some cool tricks up its sleeve! Stereo inputs retain a dual signal path from other devices, such as the UniChorus. Imaging isn’t lost otherwise passing the signal into a mono input. I should add for clarity, all EBS pedals are fine working with a mono signal ,like that of a standard bass rig.

DynaVerb is just at home in professional studio situations, too. Under the bonnet, there are dip switches that configure the effects to parallel routing. This removes the direct content from the signal path and is useful if you have a parallel effects loop on your bass amplifier and blend the dry portion in, yourself.

To power the pedals, EBS offers up 9V battery operation described in the manual. However, EBS recommend that both are better run from a power supply, such as their own AD9 Pro or the new Runsten pedalboard power supply. The DynaVerb, being a digital processor, has a slightly higher consumption, and, well, it also makes sense from an environmental point of view to use a supply instead of batteries, right?

EBS UniChorus
EBS DynaVerb Pedals

The Bottom Line

Rounding up, there’s not much to add that hasn’t been said already, but, if you’re looking for a compact pedal made by a reliable brand with clarity of sound crafted to meet the demands of the dynamic range and needs of the bass guitar, look no further./strong>

SPECIFICATIONS-EBS UniChorus Studio Edition, Rev 2
Model:UniChorus Studio Edition, Rev 2
Controls:Depth, Rate, Mode switch
I/O:One ¼” input, one ¼” output, one 2.1mm DC power input
Nominal Input Level:- 8 dBv
Input Impedance:700 Kohms
Bandwidth+0/-3 dB, 20Hz - 20kHz
Delay Bandwith:+0/-3 dB, 200Hz - 8kHz
Delay Level Mix:min/max, -oo - +3 dB
Center Delay Time:Flange: 3 ms
Chorus: 5.5 ms
Pitch Modul.: 10 ms
Modulation Depth:min/max, +/- 50% of nominal delay time
LFO Range:min/max, 0.15 - 7.5 Hz
Circuit Topology:Analogue
Housing:All metal
Dimensions:(L x W x H) 2.8 x 4.5 x 1.4" (70 x 115 x 35 mm)
Weight:235g (0.52 lb.)
Bypass:True bypass
Power Requirements:9-12V DC regulated, 35 mA max
Warranty:Limited lifetime
Price:$349 (USA), £ 173.95 (inc VAT UK)
SPECIFICATIONS-EBS DynaVerb Limited Spring Edition
Model:DynaVerb Limited Spring Edition
Controls:Reverb depth, Tone, Type switch, secondary modes switch
I/O:One ¼” input, one ¼” output, one 2.1mm DC power input
Nominal Input Level:- 8 dBv
Input Impedance:1 Mohms stereo, 500 Kohms mono
Dry Bandwidth:+0/-3 dB, 20Hz - 20kHz
Reverb Bandwidth:+0/-3 dB, 20Hz - 20kHz
Tone Low Pass Filter:min/max, 1/20kHz
Reverb Types:3 Hall, 3 Room, and 1 Reversed, 1 Gated, and 1 Spring-type effect.
Circuit Topolgy:Digital, 24-bit
Sampling Frequency:48kHz
Dynamic Range:107 dB A-weighted
Housing:All metal
Dimensions:(L x W x H): 2.8” x 4.5” x 1.4" (70mm x 115mm x 35 mm)
Weight:245g (0.54 lb.)
Bypass:True bypass
Power Requirements:9-18V DC regulated, 80 mA max
Warranty:Limited lifetime
Price:$349 (USA), £ 198.95 (inc VAT UK)