[review] Electro-Harmonix XO Key 9 Electric Piano Machine (by Tim)

Tim plays guitar in Left Passage and Endtime Odyssey.
He also teaches guitar at FullFlavour.

General impressions

The EHX Key 9 comes with just enough buttons and inputs, you don’t feel overwhelmed when faced with all the control dials. The operation of the pedal is also very easy and straightforward; you get a dry and a wet volume and two control dials. Usually Ctrl 1 is for the intensity of the effect, Ctrl 2 is to determine the speed. Last but not least there’s the voicing dial with 9 sounds to choose from (hence the name). The pedal comes with a DC adapter, it uses 9 volts like most other pedals, so it won’t be too much of a hassle to put on your pedalboard.

Electro-Harmonix Key 9 Piano MachineSounds

The Key 9 offers a plethora of sounds ranging from pads to organ. Overall I’d say that the quality of the different settings go from decent to excellent. The pad sounds don’t have me convinced as a guitarist, but they might just be the thing you were looking for. Sometimes the overtones don’t come out quite as they should but these are seldom occurrences. The great thing about the pedal is that it’s polyphonic, meaning you can use it for chords as well. Be mindful that the more notes you put in a chord, the more difficult it will be to produce a nice sound for the pedal. That being said, I felt it did an amazing job both in terms of timing and precision. My favorite settings were the very first one, which adds a lot of bass and is great for bringing a bit of atmosphere in your playing. The organ (setting 8) sounds superb as well and the vibrato (setting 3) can be fun to play around with as well.


I feel that the Key 9 is a great pedal for guitarists that want some keyboard in their music, but don’t want to have the hassle of a keyboard player in their band. Sure, you might not learn to read notation, but you get some awesome keyboard sounds and there’s one less dude you have to convince to come to rehearsal! We also shouldn’t forget about the fact that you can mingle your wet and dry sound, so you’re actually getting 18 different tones, two per setting! If you’re thinking about picking up this pedal, do try and change the volumes, they make a huge difference and can really widen or thicken your sound, depending on what you do with them. I highly recommend this pedal to anyone looking for something to make their sound a bit more interesting.

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