Echoplex

The Echoplex is a tape delay effect, first made in 1959. Designed by Mike Battle, the Echoplex set a standard for the effect in the 1960s—it is still regarded as "the standard by which everything else is measured." It was used by some of the most notable guitar players of the era; original Echoplexes are highly sought after.

Tape echoes work by recording sound on a magnetic tape, which is then played back; the tape speed or distance between heads determine the delay, while a feedback variable (where the delayed sound is delayed again) allows for a repetitive effect. The predecessor of the Echoplex was a tape echo designed by Ray Butts in the 1950s, who built it into a guitar amplifier called the EchoSonic. He built fewer than seventy of them and could never keep up with the demand; they were used by players like Chet Atkins, Scotty Moore, and Carl Perkins. Electronics technician Mike Battle copied the design and built it into a portable unit; another version, however, states that Battle, working with a guitar player named Don Dixon from Akron, Ohio, perfected Dixon's original creation.

The first Echoplex with vacuum tubes was marketed in 1961. Their big innovation was the moving head, which allowed the operator to change the delay time. In 1962, their patent was bought by a company called Market Electronics in Cleveland, Ohio. Market Electronics built the units and kept designers Battle and Dixon as consultants; they marketed the units through distributor Maestro, hence the name, Maestro Echoplex. In the 1950s, Maestro was a leader in vacuum tube technology. It had close ties with Gibson, and often manufactured amplifiers for Gibson. Later, Harris-Teller of Chicago took over production. The first tube Echoplex had no number designation, but was retroactively designated the EP-1 after the unit received its first upgrade. The upgraded unit was designated the EP-2. These two units set the standard for the delay effect, with their "warm, round, thick echo." Two of Battle's improvements over earlier designs were key — the adjustable tape head, which allowed for variable delay, and a cartridge containing the tape, protecting it to retain sound quality.

The Echoplex wasn't notable just for the delay, but also for the sound; it is "still a classic today, and highly desirable for a range of playing styles ... warm, rich, and full-bodied." The delay could be turned off and the unit used as a filter, thanks to the sound of the vacuum tubes; this is how Andy Summers uses it, for instance.

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