Electro-Harmonix Micro Synthesizer

Electro-Harmonix Micro SynthesizerElectro-Harmonix was founded in the late ’60s with the mission to produce unique and affordable effects for all musicians. Through the ’70s, Electro-Harmonix produced a number of top-sellers such as the Electric Mistress flanger, Small Stone phaseshifter, and Big Muff distortion. While the company eventually folded by the early ’80s, Electro-Harmonix is now back, offering reissues of their classic designs as well as new updated effects. Additionally, Electro-Harmonix (a division of New Sensor) now also produces a line of vacuum tubes, designed to sound like the classic tubes made from the best companies of the past, including Mullard and Telefunken.

Certainly one of the most unusual devices made for guitarists is the Electro-Harmonix Micro Synthesizer. An all-analog design, the Micro Synthesizer boasts the ability to provide the great older analog synthesizer sounds made famous by Moog, Avitar, Art and by using a guitar instead of a keyboard as the input device. Listen to Pink Floyd from the "Dark Side of the Moon" era or recall the theme music from Doctor Who and you’ll get the idea of the analog synthesizer sound. For many of us that were too young to experience the analog synthesizer’s heyday (I was only a year old when "Dark Side of the Moon" was released back in 1973), what a trip the Micro Synthesizer offers with sounds that can be explored for a new generation of players. It’s no wonder that newer bands such as Smashing Pumkins, Beck, and Moby have incorporated the Micro Synthesizer into their own palette of creative sonic tools.


The Micro Synthesizer’s operation and features look simple enough, with ten slider controls featuring four independent voices, one input and one output jack, effect on/off footswitch and power on/off switch. Effective use of the slider controls is of course the key to unlocking the myriad number of sounds from the Micro Synthesizer. The first group of sliders are for the overall "mix" of the voices, from the standard guitar tone, one octave and two octave below sliders, and a square wave slider that provides the distorted "edge." Controls are also present to control the attack time, the frequency center of the sweep range, how far the sweep range goes and how quickly the sweep occurs.

In addition, the bottom of the Micro Synthesizer has a control for setting the input volume based on whether single-coil or humbucking pickups are used. The adjustments can be made with a very small Phillips screwdriver.

The Micro Synthesizer comes with its own A/C power supply. Also included is a small pamphlet with sample settings that are a good start for using the Micro Synthesizer. Last but not least, the Micro Synthesizer comes housed in a very cool wooden storage box.


LegendaryTones was fortunate enough to speak to Electro-Harmonix President Mike Mathews about the Micro Synthesizer as well as tone in general. The Micro Synthesizer, while dubbed a reissue, uses the same components as the original units made in the late 70’s, according to Mr. Mathews. He also shared with us that the supplier of the analog chips, Panasonic, has discontinued production of the chips but that Electro-Harmonix has purchased the remaining supply. This will allow production to continue for 2-3 more years, but it is clear that it will only be a short while before even the reissue Micro Synthesizers will be considered vintage and highly collectable.

The Micro Synthesizer is housed in a medium grade sheet-metal box that is clearly not as sturdy as heavier metal enclosures. However, this does help keep some of the costs down, and with care, the sheet-metal enclosure is certainly more than adequate. Opening up the Micro Synthesizer, I saw that it uses two glass-epoxy circuit boards, one for the basic circuit itself, and one that serves to hold the slider controls as well as link the controls of these sliders (a.k.a. variable resistors) to the main board. Soldering quality looked good and I am also a fan of the use of heavy-duty SPDT footswitches like the Micro Synthesizer incorporates.


Playing a guitar through a Micro Synthesizer is unlike any other experience. It just feels more like you’ve switched instruments, rather than just stepping on an effect. The two sound files I recorded for the Micro Synthesizer are truly only the beginning with regard to offering some great sonic experimentation. For further sound files, I’d suggest going to the Electro-Harmonix sound files listed at this URL: http://www.turnstyle.com/ehx/catalog.asp?item=EH%2DMICRO&category=eheffects. Also, check out the sound files for the bass Micro Synthesizer on their site, including a recommended demo track by the bass player in Beck.

One does have to keep in mind that since this is an analog synthesizer device, you won’t get the same types of tones as you do with a modern digital synthesizer. In other words, the Micro Synthesizer won’t make your guitar sound like a choir orchestra or a piano for that matter. But this is all for the best – afterall, if you want to sound like a piano, or a choir orchestra, there are plenty of digital solutions out there that let you do that.

What the Micro Synthesizer does offer is the great analog sweeping sounds of the past. Mr. Mathew’s described the analog sound as, "warm and milky" and stated that with digital, you tend to "lose some of the feeling." After playing through the analog Micro Synthesizer, as well as with my previous experience when comparing analog vs. digital choruses, delays, and flangers, I definitely agree.

The only thing I felt was missing from the Micro Synthesizer was stereo operation. I could only imagine how much more lush and full the sounds would be through two amplifiers running in stereo, even if only offered in "quasi-stereo" by way of using opposite phasing.

One of the great things about the Micro Synthesizer is that it can be "played" like any other instrument. I found myself often tapping notes on the fret board with my left hand while simultaneously moving the sliders with my right hand for some very unusual effects (listen to Pink Floyd’s instrumental "On the Run" from Dark Side of the Moon for some ideas). For those who are looking for the old analog synth tones of the past, with real-time control, or who simply want to experience a tool that can potentially expand creativity, Electro-Harmonix’ Micro Synthesizer is the ticket.

Conclusion and Overall Rating

I chose to write about the Micro Synthesizer not because it is Electro-Harmonix’ most famous device. Certainly the Small Stone Phase Shifter or the Big Muff outsold the Micro Synthesizer; however, there isn’t anything quite like the Micro Synthesizer on the market today and that alone makes it compelling. Yes, the price at $378 is somewhat steep (often available for under $300 however), but then again, the unit is solid, built well, and unique. The term "you get what you pay for" comes to mind. Whether your interests are in making musical "soundscapes", or simply to add something new to your music, I highly recommend the Micro Synthesizer and give it a solid rating of 9.5 out of 10. We’d like to offer our thanks and appreciation to Electro-Harmonix (division of the New Sensor company) President Mike Mathews for his help and assistance with this story. Visit their site at www.ehx.com.

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