For sale is a Maestro PS-1A Phase Shifter, a classic vintage analog modulation unit from the 1970s, designed by Tom Oberheim and originally built in the USA.

This is a simple but highly musical three-speed phase shifter, offering Slow, Medium, and Fast modulation settings with the distinctive smooth, swirling character that made early Maestro phasers famous.

A true piece of vintage studio and guitar history, the PS-1A is known for its rich, organic phase tones and natural ramping effect between speed changes, delivering everything from subtle movement to deep, rotating-style modulation.

Condition:
• Vintage unit (circa 1970s)
• Fully original unless otherwise stated
• Clean and well preserved for its age
• Please see photos for exact condition

Features:
• Classic analog phase shifter design
• Three selectable speed modes (Slow / Medium / Fast)
• Warm, musical modulation character
• Simple, intuitive interface
• Iconic Maestro / Oberheim-era design

Ideal for collectors, studio use, or anyone looking for authentic vintage modulation tones that modern pedals try to replicate but rarely match.

Please feel free to ask any questions before purchase.