Design considerations for the AirProdigy Tonearm
Linear tracking tonearms are known for their ability to eliminate the distortion inherent with conventional pivot arms, which try to correct for this problem with anti-skating devices of various types (this is never entirely successful so there is always end-of-side distortion, for instance, with pivot arms).
Well-made linear-tracking arms are also known for giving higher sound quality than the majority of conventional arms.
After extensive experience operating both conventional pivot arms and linear-tracking air-bearing arms it became apparent that there is a real gap in the market for a high quality linear-tracking air bearing-arm with the following features:
Low weight to allow mounting on suspended sub-chassis turntables
Straightforward set-up for the relatively inexperienced user
The AirProdigy arm has been developed over a three-year period and has undergone extensive revision and refinement particularly in regard to compactness and ease of set-up and operation. We took as a starting point the pioneering work of Poul Ladegaard with low-pressure air bearing tonearms and the development work of Transfi in relation to the inverted air-track.
There are a number of high-pressure air-bearing arms on the market such as the Cartridgeman arm which use commercially produced cylindrical airbearings to achieve linear tracking of the cartridge across the record. Compared with the AirProdigy arm these are expensive, heavy and cumbersome and require long sub-arms to track the cartridge over the record, since the bulky air-bearing section is located beyond the circumference of the record. In comparison the AirProdigy has the airtrack mounted over the platter so the glider-arm (as we call the sub-arm) can be short and light. The low weight of the glider-arm improves tracking and minimises resonances, which degrade sonic performance, by avoiding a long, tubular arm.