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Product Review: Electro-Harmonix Synth 9 Synthesizer Machine Effects Pedal

Bob Craypoe (also known as R. L. Crepeau) is a musician, writer, webmaster, 3D artist, and creator of the Punksters comic strip series.

I recently purchased the Electro-Harmonix Synth 9 Synthesizer Machine Effects Pedal. It is an effects pedal that can make a guitar, bass, or other stringed instrument sound like a synthesizer. You just plug the guitar straight into the unit with a standard 1/4-inch instrument cable and it's ready to go. You don't need an expensive MIDI adapter or need to make any modifications to your guitar.

It has nine presets that emulate popular classic synthesizers from the past. Each preset can be adjusted with the use of two control knobs. You also have a dry volume control for the dry signal as well as a volume control for the effect. The unit has two outputs: one for the dry signal and one for the synth. If you just use the output for the synth, then both the effected signal as well as the dry signal are routed through a single output.

Electro-Harmonix Synth 9 Synthesizer Machine Effects Pedal With Power Supply.

Electro-Harmonix Synth 9 Synthesizer Machine Effects Pedal With Power Supply.

Test One: Using a Gibson Les Paul

The first instrument I plugged into the unit was my 1992 Gibson Les Paul. I tried the synth sounds by themselves to see how it would sound and they did, in fact, sound like a genuine synthesizer. No joke here.I went and tried each of the nine preset sounds. I played with the control knobs a little to check the variations in sounds and there were some decent editing capabilities.

Then I turned the guitar volume up and had a mix of the guitar with the synth sound and it was very nice. Most of the presets made it sound like an organ was backing up the guitar and a few of them had some fancy synth-like sweeping effects backing up the guitar.

The sound I liked most on the first try was the strings sound. Preset 8 is the String Synth. Control knob 2 allows you to delay the strings sound so that the volume increases slowly. Basically, it adjusts the attack time. I had the guitar's dry signal going through an effects pedal that had an acoustic guitar simulation effect, so it sounded like an acoustic guitar backed up by a strings section. The String Synth sound was very warm and when combined with the acoustic guitar simulator, it was a very full orchestral type of sound. I was very pleasantly surprised.

The tracking was good. There were no issues with a significant delay from the time I plucked a string to the time when the synth sound was heard, so that was a good thing. One issue, though, is when you go into about the 22nd fret or so, the tracking for it kind of goes out the window. So there are some frequencies where the unit's tracking does not work. As far as a bass guitar goes, the tracking fails when you go below the open A string. But you could get around that if you run the bass through an octave pedal that raises the pitch of the bass an octave and just have the raised octave sound go into the unit. So there are some ways around some of the various issues if you are a creative problem solver.

Manufacturer's Promotional Video

Test Two: Eastwood Classic 12 Semi-Hollowbody 12-String Electric Guitar

The next instrument I tried out was my Eastwood Classic 12 Semi-hollowbody 12-String Electric Guitar. I was curious as to how a 12-string guitar might sound. The clean sound was routed to an effects pedal using the acoustic guitar simulation effect and I used the Strings Synth preset on the synth 9 unit, set to have a slow attack time. It sounded beautiful.

After I tried the String Synth preset, I went through all of the others. Some had some nice sweeping synth sounds and others sounded like the 12-string had an organ backing it up. Initially, I was curious as to whether or not there might be some tracking issues with the use of a 12-string but there were not any to be found. It worked just as well as a 6-string guitar, provided that you didn't go up above the 22nd fret or so.

Eastwood Classic 12 Semi-hollowbody 12-String.

Eastwood Classic 12 Semi-hollowbody 12-String.

Test Three: Morgan Monroe MMT-1E Electric T Style Mandolin

The next instrument I plugged in was a Morgan Monroe MMT-1E Electric T Style Mandolin. It is an electric mandolin shaped like a Fender Telecaster guitar, with two single coil pickups. I was first wondering what a mandolin would sound like with the synth pedal and wondering how the tracking would be with a mandolin as well. All of the information provided on the various websites only mention how it works with a guitar or bass. There was no mention of how it worked with a mandolin.

Preset one, which is the OBX preset, was the first thing I tried. It worked very well with the mandolin until I tried to go above the 12th fret. Then the tracking failed. I could probably get around it by using an octave pedal to make the input into the Synth 9 unit an octave lower but I did not try that. However, everything I played below the 12 fret on the E string tracked well and sounded great.

The OBX preset played an octave lower in pitch for everything the mandolin played. This created a very full sound. I was extremely pleased with the sound. The strings sound was about the same pitch as the mandolin and did not create as full of a sound as a result. But I think that could be corrected with the use of an octave pedal running from the mandolin, into the Synth 9. that would also correct the tracking issue that occurs above the 12 fret of the E string.

Morgan Monroe MMT-1E Electric T Style Mandolin.

Morgan Monroe MMT-1E Electric T Style Mandolin.

Test Four: Zoom G1on Guitar Effects Pedal

Test number four involved the use of a Zoom G1on Guitar Effects Pedal. This particular effects pedal had loads of effects like chorus, reverb, delay, phaser, flange, pitch shifter, distortion, fuzz, auto hah, you name it. It's all in one single unit with loads of editing capabilities for each effect. You can have multiple effects simultaneously and you can even place them in any order that you want.

I tried the Synth 9 unit alone, with no guitar sound. It was just the synth sound running into the Zoom pedal. I tried it out with chorus, delay, reverb and a few other commonly-used effects. I tried each of Synth 9's presets with the various effects on the Zoom pedal and the sound was amazing.

Between the various presets on the Electro-Harmonix Synth 9 and the adjustments that could be made on each one and the numerous effects on the Zoom pedal, there are a multitude of combinations that could be created that would provide an infinite number of sound options. It's just amazing really.

Zoom G1on Guitar Effects Pedal.

Zoom G1on Guitar Effects Pedal.

Tracking Issues

Like I have stated above, there are certain tracking issues. I have read online about some people having to adjust their picking attack in order for the tracking to be okay but from my experience, there are not a lot of issues with that. But some tracking issues can be corrected with the use of a compressor going into the input of the Synth 9 unit. that would even out the volume when you have a variation in the dynamics of your playing.

Other tracking issues have to do with the pitch itself. When you go above the 22nd fret on the high E of a guitar, or below an open A on a bass guitar or above the 12th fret on a mandolin. In some cases, with the mandolin, if you do a very fast tremolo, there may be some breaking up in the sound, on some of the presets on the Synth 9 but on most, it works very well. Strumming on either a mandolin, 6-string guitar or 12-string guitar all work very well.


Basically everywhere I looked online, the price was the same. It was the same at Amazon, Sweetwater and a few other places online. The unit went for $221 on all of the websites where i had looked. The only real difference in pricing will be if you order it from a place that has free shipping or not or from a company located in a state that does not charge sales tax for online purchases. That's really the two big things I look for. then the next item of consideration would be the return policies.

Electro-Harmonix has a lot of pedals and effects units that they manufacture. Some are quite expensive and others are fairly cheap at $221. This unit is probably somewhere in the middle. Overall, it does a lot for its price. It's really a matter of whether or not you think it is something you would want to add to your sound capabilities. if you are a guitarist looking to add synthesizer sounds to your band situation and don't want to have to drag around a big keyboard, this pedal just might be for you. it may cost as much as a portable keyboard but it takes a lot less room onstage or in your car when you are transporting your gear.

The Bottom Line

The bottom line is that I feel the Electro-Harmonix is worth the price. I play keyboards but have always been reluctant to play them in a band situation because I already lug around a sound system, a couple of guitars and a mandolin. So lugging around a keyboard and a keyboard stand would just be more of a nuisance. But carrying around this compact unit that can give me that synthesizer sound is so much easier. Not to mention the fact that I can get the sound of the guitar and the synth at the same time to really create a full sound. All I can say is that I'm happy with it.

© 2017 Bob Craypoe


Bob Craypoe (author) from New Jersey on July 30, 2017:

I have a Gretsch myself. I inherited it from my grandfather. It's almost as old as i am. Just a few years younger.

lori811 on July 30, 2017:

A very well written and interesting article. I come from a line of musicians. My dad was a drummer, had his own band. I chose the piano but was persuaded to play the guitar. Owned a Gretch with amps which was short-lived when my fingertips hurt from the calluses. Have fun with your new toy. Embrace and enjoy your music:)