-=> Quoting Kevin Jones to All <=-
 KJ> Okay, I have 2 different tape decks that I've done some recording on. 
 KJ> The first is a Sanyo it's about 13 years old.  The second is a Sony
 KJ> and it's a 1996 model.  Now the Sony has automatic HxPro for recording
 KJ> I recorded the  same song twice on a metal tape.  Once on the sony and
 KJ> once on the sanyo.  recording both with Dolby C NR and on the type IV
 KJ> tape setting.  To my surprise, the sanyo recording had clearer highs. 
 KJ> Not believing my ears I tried the same test but instead of a metal
 KJ> tape I used a type II.  Still, the old Sanyo ruled supreme.  The sony
 KJ> recording has more high frequency noise, when apparently HxPro is
 KJ> supposed to reduce high frequency noise and distortion.  Is anyone out
 KJ> there noticing anything similar or have any reasons?  I'd like to hear
 KJ> from you.  Thanks! 
The HXPro system (Headroom eXstention Professionl) is a system by which
the AC bias fed to the record head varies with the amount of high
frequency content of the program being recorded.  This improves many of
the problems associated with the analogue cassette format.  High
frequencies that are audible also act as "bias" for low audio
frequencies, thus by varying the bias, a more optimum recording can be
made.  Remember that Dolby HXPro is used regardless whether noise
reduction is being used or not.  It's primary function is improving the
recording linearity and reduction of distortion only, and allows
recording at a higher level without adding significant amounts of
distortion.
As to the differences between the two decks, that could be a number of
factors.  Head wear, head asymuth, whether it needs head
demagnatization, head cleanleness, playback EQ accuracy, calibration
accuracy, head contact with tape, recording level accuracy plus a whole
slew of other factors could come into play to cause one to sound
"brighter" than another.   Note also that if both machines have a
different head alingnment, that can also adversly affect the preceved
clearity of recordings also.
Just some ramdom thoughts. :-)
See ya, Cameron Hall
cameron.hall@bluebeam.gryn.org | ad121@freenet.hamilton.on.ca
Blue Beam BBS | 905 662 5784 | Stoney Creek Ontario Canada | v34 vFC FAX
--- GEcho 1.00
---------------