Echoplex

The Echoplex is a tape echo machine: a dedicated delay unit that records your guitar onto a loop of magnetic tape and plays it back moments later. Designed in 1959, it is regarded as the first stand-alone delay effect for guitar, and its descendants, the EP-1, EP-2 and EP-3, defined what tape delay sounds like for a generation of players¹. Its contemporaries were the Roland Space Echo and the Binson Echorec, but the Echoplex earned a second life that none of them matched: its solid-state preamp, originally just the stage that conditioned the signal on the way to the tape, became one of the most copied circuits in modern boost pedals¹.

Where the Echoplex came from

The Echoplex is the brainchild of Mike Battle¹. The classic tape delay was designed in 1959, and the Echoplex EP-1 followed in 1961 from Mike Battle, ahead of the Roland Space Echo of 1974⁴¹. Writing at Stompbox Book, William Weir calls it the first stand-alone delay effect for guitar, a box that freed players from needing a studio tape machine to get echo¹.

The first Echoplexes were retroactively known as the EP-1⁵. The rights to use the Echoplex name and designs were purchased from Harris-Teller by Jim Dunlop a few years before one published account of the unit's history, and at that time replacement tapes could be ordered directly from Dunlop⁵. The EP-3, originally released in 1970 as a solid-state update to the previous tube-based versions, outlasted the tube models². The EP-2 preceded the EP-3 variant⁵, and today the tube EP-2 is hard to find, costs a lot, and is not easy to repair, though that has not stopped collectors from seeking it¹.

How the tape echo works

At heart, the Echoplex is essentially a tape machine with two playback heads, one that repeats milliseconds after the first¹. Your signal is recorded onto a loop of tape inside a removable cartridge, and the spacing between the record and playback heads sets the delay time. Moving the playback head changes that spacing, which is how you dial in the delay length. Dedicated delay units such as the Echoplex and the Roland Space Echo used magnetic tape for their echoes in this way, as Strymon's Matt Piper explains in the company's history of echo machines⁶.

Tape echo is a mechanical instrument, and the mechanics wear out. Echo Fix, which supplies service parts for vintage units, lists the failure modes plainly: faulty rubber rollers, drive belts, tension springs and tape can lead to wow and flutter, pitch variations, low echo output signal and tape transport problems⁷. The tape itself is a consumable, and Echo Fix's service guidance for both the EP-1/EP-2 and EP-3/EP-4 families says the tape should be replaced every 300 hours⁸⁷. Their service kits include splicing tape tabs for rebuilding cartridges, and they sell a replacement record/erase head that fits the EP-3 and EP-4⁷⁹. For the EP-1 and EP-2, Echo Fix offers an updated red rubber roller that buyers describe as an excellent improvement on the original rubber roller¹⁰. Fulltone tape is also sold for DIY cartridge reloading across the EP-1, EP-2, EP-3 and EP-4¹¹.

Echo Fix also builds the EF-X3, a modern tape echo of its own, and addressed the wear problem directly: the company implemented a new auto tape stop circuit to extend tape life¹². The EF-X3 Tolex version adds CV control for motor speed and feedback level (0 to 5V) via compatible expression pedals, so delay time and repeats can be swept like any pedal control¹³.

The EP-1, EP-2 and EP-3

The three versions players care about are the EP-1, EP-2 and EP-3¹.

The EP-1 and EP-2 are the two earliest versions, and they are the last of the Echoplexes to feature tubes, housed in what looks like an old tool box¹. Today they are hard to find, cost a lot, and are not easy to repair, though that has not stopped collectors from seeking them out¹. In the 1960s and 1970s, Echoplex tape echo units evolved from tube-based designs into solid-state designs, and the EP-3 is the notable result¹⁴.

The EP-3 had its own variations and revisions to the circuit¹⁴. Catalinbread, whose Epoch Bias pedal is built on this circuit, notes that the first few hundred EP-3 units that came off the assembly line featured a slightly different preamp circuit than the rest, one that is a little brighter¹⁵. Strymon studied a very special Echoplex EP-2 for its EC-1 pedal, a unit that had been worked on by technician Cesar Diaz; the modifications included tweaks to the tube preamp for a warmer sound closer in frequency response to an EP-3, seemingly aimed at bringing the best aspects of the various vintage Echoplex models into a single unit¹⁶¹⁷.

The EP-3 preamp and its sound with the echo off

The EP-3 was prized as much for its tone conditioning ability as for its tape echo effect¹⁸. Inside, an internal secret preamp was at work, boosting and fattening the signal, along with a slight phase shift that altered mid and high frequency harmonic content¹⁴. That preamp stage of the 1970s EP-3 became legendary on its own, independently of the tape echo it fed, and became a best-seller in the 2000s as the EP Booster pedal¹⁹.

The preamp is a JFET circuit. The JFET architecture is found in the preamp section of the Echoplex EP-3 tape delay, as Strymon notes in its circuit documentation²⁰. Not every original unit behaved the same: some EP-3s dropped in signal due to wrong TIS58 JFETs being fitted¹⁴. The original preamp also ran from a zener-regulated supply of about 20 Volts DC, higher than a typical 9V pedal supply, which matters to anyone cloning the circuit²¹.

Players discovered they did not need the echo to benefit. The preamp of this tape echo was used by many musicians as a boost alone, without the echo effect, to add character and boost the signal before the amp²². Anasounds names Eric Johnson among them: many musicians, such as Eric Johnson, used their tape echoes in a different way, using the preamp alone, without the echo, as a dirty boost to overload amps²³.

Pedals based on the Echoplex

The EP-3 preamp and the tape echo sound have both been carried into modern pedals, in two separate lineages.

Preamp clones and boosts:

• Dunlop EP101 Echoplex Preamp: Dunlop's EP101 recreates the magic of the EP-3's front end, featuring a Field-effect Transistor (FET) just like the original, following the same signal path¹⁸²⁴. Its Gain control allows you to boost your signal by up to +11dB, with light asymmetrical clipping at higher settings for organic grit¹⁸. It comes in a heavy-duty Phase 90-sized housing with a replica EP-3 knob, true bypass switching and a status LED²⁴, and is made by Dunlop Manufacturing²⁵. Iron Maiden's Janick Gers uses the Echoplex Preamp²⁶.
• Xotic EP Booster and EP Pro: Xotic says it captured the magic of the EP-3 echo machine pre-amp in the EP Booster²⁷, and the EP Pro builds on that pedal, which captured the legendary Echoplex preamp sound²⁸.
• ClinchFX EP-PRE: a JFET preamplifier based on the preamp section of the Echoplex EP-3 tape echo unit²¹. Its charge-pump power supply converts 9 Volts to more than 17 Volts, and 12 Volts to just over 23 Volts, recreating the dynamics of the EP-3's original supply²¹.
• Chase Tone Secret Preamp: built on the Maestro Echoplex EP-3 preamp, the solid-state design with its internal secret preamp¹⁴.
• Anasounds Utopia Deluxe: traces its lineage to the Echoplex EP-3 preamp stage of the 1970s¹⁹.
• Goodrich Updated Baby Bloomer: inspired by the early Echoplex units, particularly the Maestro EP-2 and EP-3 circuits²⁹.

Tape echo emulations:

• Empress Echosystem: its Echoplex mode emulates the classic Echoplex EP-3³⁰.
• Line 6 Tube Echo: a model based on the EP-1 Tube Echoplex, found in the TonePort KB37's stompbox and studio effects³¹.
• Universal Audio Starlight Echo Station: its Tape EP-III effect models vintage early-'70s tape echo units³². UA's Orion Tape Echo takes the same approach; UA notes that if you run a stereo rig you might want a delay with stereo outputs, but there has never been a stereo Echoplex³³.
• Strymon EC-1: developed from Strymon's study of a modified EP-2¹⁶¹⁷.
• Wampler Faux Tape Echo: one of a number of digital pedals that emulate the sound of those machines¹.

DIY EP-3 preamp builds

For players who want the EP-3 preamp without a vintage unit, Dunlop Manufacturing makes the EP101 Echoplex Preamp, a standalone preamp pedal¹⁸. It comes in a heavy-duty Phase 90-sized housing with a replica EP-3 knob, true bypass switching, and a status LED²⁴. The original EP-3 preamp section was released in 1970 as part of the solid-state update to the previous tube-based versions, and it is this circuit the pedal reproduces².

The EP-3's preamp has a documented history of its own beyond the stock unit. The EP-2 that preceded it was the second Echoplex design and the last to feature a tube preamp, and one heavily modified EP-2, worked on by Cesar Diaz, became a sought-after build on the vintage market⁵. Diaz's mods created a single unit combining what reviewers described as the best attributes of both tube and solid-state Echoplexes, making for a warmer sounding unit closer to an EP-3⁵. That modified EP-2 showed up in pristine condition and sounded amazing, according to the review that documented it⁵.

Pedals on this page

Binson Echorec

Binson · Delay

$2,000 list price

Maestro Echoplex EP-3

Maestro · Delay

Roland Space Echo

Roland · Delay

$500 list price

Echo Fix EF-X3 Tolex

Echo Fix · Chorus

Catalinbread Epoch Bias

Catalinbread · Preamp

$179 list price

Strymon EC-1 Single Head dTape Echo

Strymon · Delay

$279 list price

Xotic EP Booster

Xotic · Boost

$118 list price

Chase Tone Secret Preamp

Chase Tone · Preamp

MXR Phase 90

MXR · Phaser

$99.99 list price

Anasounds Utopia Deluxe

Anasounds · Delay

Universal Audio Starlight Echo Station

Universal Audio · Delay

$300 list price

Strymon EC-1

Strymon · Delay

$279 list price

Wampler Faux Tape Echo V2

Wampler · Delay

$239.97 list price

Universal Audio Orion Tape Echo

Universal Audio · Delay

Empress Effects Echosystem

Empress Effects · Delay

$449 list price

ClinchFX EP+

ClinchFX · Boost

$149 list price

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