Dear Don: I made several cassette recording copies ( mainly from LP ) through my Nak 700 ZXL ( that I still have ), I made it in different ways: with Dolby C, with DBX and with out any noise reduction system.
The best quality cassette performance were on that recorded cassettes where I don't use any noise reductio device.
The noise reduction system is a " heavy " signal proccess that makes a signal degradation. OF course that everything is on the trade-offs that we choose.
Like any audio device a cassette deck is a " whole " item: quality of the tape heads, quality of the cassette mechanism, quality of the electronic design, quality of the lay-out, quality of the electronic parts, quality of the execuion design, facilities ( like the auto-calibration on my machine and other Naks mahnes. ), etc, etc. As a fact IMHO the noise reduction is not the main/important subject on a cassette machine.
I achieve a " new "/high quality performance level when I buy the 700ZXL service manual and change ( mainly caps and resistors ) several passive parts where the signal pass through for better ones, IMHO it is worth to take the effort to do it.
In those times I heard several cassette decks including Tandeberg but not your specific Teac model and IMHO no one beats the original Naks due not only on its high/superb quality build/design but for the auto-calibration system too.
As almost always the quality is system dependent and " ears " dependent too.
Don, the important subject is that you are having great fun with your Teac, good!
Regards and enjoy the music.
Raul.
