The 550A EQ, one of his most famous innovations, was first released in 1971.
Hand-built and hand-wired, there will only be 50 units available.
The features, according to API, include:
- Hand-wired Limited Edition model with 50th Anniversary Faceplate
- Reproduction of the legendary 1971 550A
- 3 bands of classic API equalization
- 5 selectable frequency centers on each band
- High and Low bands offer shelf/peak switching
- "Proportional Q" narrows filter Q at extremes
- Switchable band pass filter
- Individually Serialized (1-50)