This is the only cassette deck I have that is capable of encoding and decoding the dbx noise reduction system. dbx was also used on records and this unit is capable of decoding that as well (this would be used with the "tape loop" or "tape monitor" function on your receiver).
The first scary "snap" you hear is the mechanism resetting itself (as it should do) after being reassembled and powered on for the first time. The second is my twanging the eject button.
Interestingly, although all of the RS-M14, 218 and this 234X use the RS-M2 mechanism, automatic tape-type detection is not supported on the M14. (The M14 also supports the obsolete FeCr type III tape, where the other two do not.)
The Technics RS-M234X supports Dolby B and C noise reduction in addition to the dbx method.
As found, this deck was advertised as "working perfectly". It didn't--yet in all fairness the seller refunded my money (and I did tell them that I planned to fix it). Many months later, here I am fixing it. Although it had the usual poor speed regulation problems, it had another, more perplexing problem where it would "flip" the tape over after running it past the leader. I'd actually have to take a cassette apart to fix it, and I'd never seen anything like this happen before. The problem was especially prevalent on longer tapes, which are thinner than shorter ones. The audio would also randomly cut out on the playback or recording modes, due to a dirty switch. New belts cured all the transport problems and cleaning the record/playback mode switch has (almost completely!) eliminated the audio cutout problems.
dbx noise reduction never enjoyed much success as a cassette or record noise reduction system, due mainly to the fact that it did not sound acceptable when played back on equipment without a dbx decoder. Some people also felt that the compression and expansion effects were too pronounced, and machine alignment was critical with dbx, much more so than Dolby B (or even C) noise reduction. However, dbx was used as the noise reduction standard for MTS (stereo) television audio in the US and it also found plenty of use in wireless microphone systems.
9 июн 2011
