This is the original, first version (V1), of the Small Stone phase shifter introduced by Electro Harmonix in 1975. I bought it new in Gainesville Florida in 1975. 

It has been out on the road a little, but has been in a studio setting the last 40 years or so.  As such it is in very good condition which is not common for pedals this old.   This is a classic, vintage pedal used by many musicians on many records.  The design and sound is unique among other phase shifting pedals because Electro Harmonix used four EH1048 (their own part and part number) transconductance  amplifier chips rather than Op Amps..   The transconductance amplifier converts the input signal voltage to current, and the effects are current, rather than voltage generated (as would be the case in the more typical Op Amp/FET designs).  This pedal was made in the USA, and as you can see in the photographs, it involved a lot of hand wiring and soldering.   The output level is the same whether in effect or bypass mode.

If you are not familiar with this pedal, it creates a range of swishing, Leslie speaker-type, phase changes to the sound.  You control how fast (like controlling the speed of rotation of a Leslie Speaker) with the rate knob on top and how pronounced you want the sound via the slide switch. In practice, changes to the rate also change the depth of the effect to the point that at the full clockwise position it creates a warbling sound.  At the low setting, there is simple a gentle washing sound, like waves on the beach.

Although you can use this pedal for some exaggerated effects, I always found it best for very slow subtle, phase changes that a listener might not even notice.  This is particularly useful on electric acoustic guitars as it adds warmth and color to the sound.

I am selling all of the equipment I have collected since the sixties. I only sell equipment purchased new by me, and played only by me.  I test everything before I sell and ship it.