Maestro | PS-1 Phase Shifter

In 1971 a new effects device hit the musical instrument market and made an immediate impact on the sound of the electric guitar. That device was the now-legendary Maestro PS-1 Phase Shifter. Within weeks of its release, the sound of phase shifted guitars and keyboards began resonating over American radio airwaves and the phase shifter craze was on. Almost immediately, other manufacturers followed suit and began offering phasers of their own design in an effort to cash in on the new phase shifter fad. However, the Maestro Phase Shifter was and still is the original.

The PS-1 ruled as king of the phasers for quite some time, and although it was eventually replaced by units that were smaller and less expensive, the Maestro PS-1 remains unique in many ways. In fact, the Maestro Phase Shifter has never really been equaled. Even today, it continues to be championed by loyal enthusiasts, and some thirty years after its release, the sound of the Maestro Phase Shifter can still be heard whirling and swirling on new recordings.

The Maestro Phase Shifter was not intended for floor operation; rather, it was designed as a table-top type of unit. The chassis is made from bent sheet metal. The top of the unit is slightly angled for improved visibility of the control panel. A rather thick plate is welded to the bottom of the unit and is threaded for a standard microphone stand; in this manner, the unit can be attached to a mic stand and conveniently placed near the guitarist on stage for easy access to the controls. A six-pin Molex type connector located on the rear of the unit provides connection to an optional three-button footswitch that duplicates the operation of the three buttons, providing remote foot control of the phaser.

Three colorful buttons located on the top of the unit select the phasing speed. The buttons are appropriately labeled SLOW PHASE, MEDIUM PHASE, and FAST PHASE. The SLOW PHASE button also functions as the bypass switch. Interestingly, the three colorful plastic buttons were the same as those used on Lowery organs. CMI also owned Lowery at the time and suggested the use of the colorful Lowery buttons for speed selection. One unique and very cool aspect of the Maestro Phase Shifter is the fact that the phasing speed ramps up or down when changing from one speed to another, similar to a Leslie rotating speaker cabinet. This feature is not to be overlooked or underemphasized!!! The dynamic effect produced by the ramp-up/down feature sounds absolutely superb when used by an accomplished musician – no other phaser offers this feature and that alone makes the Maestro Phase Shifter worth the price of admission!

The Maestro Phase Shifter is AC powered and uses a non-polarized AC cord. A switch on the top of the unit turns it on and off. A fuse is provided on the rear of the unit. The classic Maestro emblem with its three colored “trumpets” is proudly displayed on the top of the unit.