When I was a kid in the seventies, the only game in town for echo was the Echoplex. Any guitar with echo you heard in the seventies was probably done on a Plex. Certainly all my guitar hero's back then used one. Just to mention a few: Tommy Bolin, Jimmy Page, Joe Walsh, Brian May, and last but not least, the man with the guitar, James Marshall Hendrix. I couldn't afford one back then, and now I have two.

I did a lot of research and learned a lot. The Echoplex was invented by a man named Mike Battle and had several incarnations:
  • EP-1: The first tube model from the early sixties.
  • EP-2: The second tube model from the late sixties.
  • EP-3: The first solid state model, early seventies
  • EP-4: The second solid state model, mid to late seventies
  • Sireko: Economy model from early seventies, same electronics without SOS, used a different tape cartridge.
  • EM-1: Multi-Channel tape echo unit from the early seventies.
My first Plex was a 1974 EP-3, given to me by my good friend Maynard. It was in pretty shabby condition when I took possession, it wasn't even working. However, I'm a fool for vintage gear so I went to work on the restoration, see below for a link. My second Plex is an 1968 EP-2 that I acquired in a trade. It is in need of restoration badly which I haven't gotten to yet, see below for a link.

Some notes about the Echoplex
  • I recommend rebuilding your Plex like I did. At this writing, it's 2008. The newest your Plex could be is 25 years or so if it's an EP-4, even older if it's an EP-3. If its a tube model it's probably from the 60's. That's damn old for a mechanical device and unless it's a closet classic it will need some restoration.
  • When you first get your Plex, you should: Clean it inside and out, change the belt, and get a new tape cartridge.
  • More complex restoration actions include lubrication, replacing the electrolytic capacitors, changing the motor mounts, (I don't know where to get them, but I'm working on it) and adding a grounded cord if it doesn't have one, although you could get ground loop problems with some amps if you do that. Most solid state models probably don't need a cap job unless you are having bad hum problems, but the tube models with the old paper or can caps should definitely have the them replaced.
  • The Echoplex tape runs CONSTANTLY when powered up, whether you have the echo engaged or not. Shut it down when you are not playing to preserve the tape and prevent wear on the Plex itself.
  • KEEP IT CLEAN!! Like I said above, the tape cartridge runs CONSTANTLY when powered up, whether you have the echo engaged or not. If you are playing a 3 or 4 set gig, how many miles is that tape traveling? See what I mean? Clean the tape path regularly, and often. See the link below for details on how to clean an Echoplex.
  • Every now and then there are Ebay auctions for NOS, vintage tape cartridges. DON'T USE THEM!! Tape formulations have changed dramatically in the 30 years since your Plex was built and adjusted. Use a modern, new tape cartridge, the quality is considerably better. Or, reload your old cartridge with new tape.
  • Have the Plex biased properly to the new tape cartridge you are using. Once biased, you don't have to do it again until or if you change tape formulations. See below for instructions on how to do this.
  • Schematic Heaven has the Echoplex service manual for download, and there are regular auctions for hardcopys of it in Ebay, get yourself a copy.
  • The supplies for vintage Echoplexes isn't going to last forever. Below are links to pages I've created on refurbishing pressure pads and reloading tape cartridges to stave off the inevitable.
I heartily recommend getting a Plex; there are always several of them on Ebay. Be aware that it will probably need a tune up like I gave mine, and regular maintenance, but its worth it!
The Fantastic Echoplex
Echo chamber
My Gear Page
Since I first put this page up I've had more hits and more response to it than any other page on my website. I've received emails from all over the world with questions and comments about it, and I want to thank everyone for their good wishes. Due to it's popularity I've revamped the page and added several more expanded pages about different issues regarding the Echoplex. Please remember that I am not a trained technician, nor do I do repairs, I am just a DIY homebody that did a lot of research on the Echoplex, then consolidated it here for other Plex owners to benefit from. See below to get started!!!
Here are links to other pages I've done on the Echoplex:
My 1974 EP-3 I refurbished and restored.
My 1968 EP-2.
How to clean an Echoplex.
Build yourself a stand for your Echoplex.
My Echoplex survival kit.
How to reload a tape cartridge.
Repairing a pressure pad.
How to adjust tape bias an Echoplex, copied from the original service manual.
Removing the EP-4 compressor board.
My Commentary on tape and parts availability for the Echoplex.
Mike Battle:1918-2008
A solid state EP-2!!
A tube EP-3!!
Here are some external links:
JOA: Lubricated tape for reloading cartridges, also splicing blocks, Q-Tips,and other cleaning supplies.
Andrews Amp Labs: Jeff takes repairs on a case by case basis, call or email him.
Orbit Electronics: Echoplex repairs and new tape cartridges.
Good page here on cleaning and demagnetizing tape recorders.
Schematic Heaven has the Echoplex service manual and schematics of all the Plex's.
The CartGuys: Another source for lubricated tape. Look for "Echoplex 850-X".
Splicit.com: Splicing blocks and cleaning supplies, also tape.
Articles here and here from Vintage Guitar magazine about the Echoplex.
Article here from Mix magazine by Eddie Ciletti about Echoplex maintenence.
Antique Electronic Supply: Tape cartridges, pressure pads, belts, thumbscrews.
Loop Master has a tape cartridge rewinding service.
Good article from Tape Op about tape splicing.
Terry's Rubber Rollers and Wheels rebuilds pinch rollers, I sent him mine.
Parts is Parts has Echoplex motors and belts.
Plex schematics here.
The late Mike Battle invented the Echoplex.
Small page about the EP-3 and EP-4.
Caig makes the correct rubber cleaner for your pinch roller.