Hello.
Do you know if the digital output from an analogue cassette is compressed with PASC or not? I guess not, but I’d like to know more. The output is at 44,1 KHz; is it possible to have it at 48 KHz? If yes, how?
Thanks
DCC recorders have A/D converters that can only encode at 44.1 kHz, so when you play an analog cassette, the digital audio comes out of the digital output at 44.1 kHz, But the only reason to use 48 kHz would be if the cassette had any audio signals about 22 kHz on it, and I doubt that any analog tape was able to record audio frequencies that high.
The PASC chips can only encode or decode, they can’t do both at the same time. When you play an analog tape, the analog signal from the heads goes through the Dolby B/C decoder if you set Dolby on, and then goes into the A/D converter. The A/D converter generates an I2S signal that gets converted to SPDIF (PCM) for the digital output. The PASC chips aren’t involved in that process (and couldn’t be involved; it’s just not possible).
===Jac
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Thank you very much, Jac; it’s as I suspected.
Actually there are some TOTL cassette decks that have frequency response above 22 kHz (some go up to even 27 kHz) and they can record that (especially on type IV metal tapes).
Other thing is that DCC deck aren’t that capable when it comes playback of analog tapes, for instance DCC900 has frequency response range 30 Hz-16 kHz written in service manual.