Maestro PS-1A

Here’s the Zeta Sound Maestro PS-1A Phase Shifter clone.  So what differs from the original.

  • Power single 12VDC 
  • A new transistor input buffer suited for guitar
  • 2N5952 fets instead of the original 2N4303
  • TL072 opamps in the signal chain instead of the 1458:s
  • Adjustable high speed and depth from the bottom lid
  • The speed selector circuit, tap the switch and change the speed through three presets  Slow (1Hz) -> medium (2Hz) -> fast (7Hz)
  • Hosted in an Eddystone BB enclosure 120x95x34mm

MaestroPS-1A V2 Clone zeta-sound

Presets demo




Eko is an analog delay based on Scott Swartz analog delay, two BBD circuits (V3205) gives about 400mS of analog delay.

The Unicorn MKII
The unicorn MKII is an update of The Unicorn, I’ve added modulation on the wet signal, from slow wobble to fast oscillation by the knobs  Speed and Depth. Thanks to Björn who has contributed with the soundclips.


3MOVIBR8 is a two effects pedal, selectable by the Trem/Vib switch. The vibrato circuit is based on the Boss VB-2 and the tremolo is basically an EA tremolo


VB-3 Speedster
A circuit based en the Boss VB-2 vibratopedal. It has been rebuilt in the rampsection, allowing it to speed up the vibration in rate. The rampknob then controlls the acceleration of the rate. Developed with involvement with Björn Greder who has contributed with sound1, in sound2 and 3 he has used the speedster with The Unicorn. Last clip is recorded by me to demonstrate the ramp function.


A 600mS analog delay, truebypass, built around three V3205BBD circuits. Controls for Level(level on the repeats), Boost(about 24db off volume boost is accesdible), Echoes(number of repeats), Time(delay time), + an internal trim pot accessible through the bottom of the pedal, which controls the total amount of hi cut. The soundfile is contributed by Nut.


The Unicorn
The Unicorn is an analog delay of my own design, three BBD circuits (V3205) gives about 600mS of analog delay. Soundclips are recorded by Björn Greder.


Slimy Vibe
A vibrato effect with knobs for Blend, Speed and Depth. It goes from 1.8-12Hz in speed. This is an ongoing project.


Boss VB-2
A modified version of the original. The mod is a chorus mode and truebypass. Last clip is in chorus mode.


ESP reverb
A stand alone spring reverb, recorded in the effect loop of a solid state amp.

Digital Delay
A delaypedal based on the Princeton PT2399 delaychip.