Introduced with the DR-14 in 1949. This little gadget was soon produced on its own and was well reviewed in all Hi-Fi magazines.
It allowed the user to play all formats of records on one machine by filtering frequencies to match different types of records.
The RIAA (Recording Industry Association of America), equalization specification was introduced in 1954 to align all record companies to record at the RIAA standard. Before this each recording company had their own standard and often each recording technician set his own. Playback became a problem as different reproduction results were obtained if the recording and playback filtering were not matched.
This little device compensated for that allowing each type of record to be correctly matched
£4.10.0 in 1952