top of page



High Resolution Stepped Variable Speed Oscillator

Introducing The VS-20 mastering grade variable speed oscillator. Unlike the original Ampex VS-10, the VS-20 is fully self contained and will control the capstan speed on any analog recorder that utilizes 9600 Hz as standard servo reference frequency. The VS-20 control frequency is digitally generated and features a large, bright 5 digit percent of nominal speed read-out. It’s glitch free 0.01% speed steps from nominal speed allow very fine pitch changes with 25 ppm repeatable accuracy. A large VSO in / out switch allows easy comparison of pitch from nominal.

VS-20’s are supplied in a rugged plastic case with complete Ampex ATR-102 connecting cable (others available at extra cost) and UL approved external power supply and rear panel mounted power switch. Now you can utilize VSO control that features undetectable .01% speed steps with no speed drift or increased wow and flutter.

VS-20 Specifications:
Reference Frequency: 9.600 Khz, TTL level
VSO Range: from 50% to 200% of nominal speed
Resolution: 0.01% – from 50% through 200% of nominal speed
Frequency drift: 25 ppm maximum through entire VSO range.
Display: Five digit seven segment LED.
AC mains: 117 V, 60 Hz. nominal. Other voltages available.
Physical: 5.3” wide 5.3”depth 2” height, weight 6 lbs.

bottom of page