[net.audio] Tape Decks

wjm@whuxj.UUCP (MITCHELL) (02/27/84)

Four general comments related to tape decks and some recent net.audio articles
1.  The comment that Nak decks don't need tapes with a "hot" high end since
they have excellent high frequency response, is like many things said by audio
salespeople, based on a fact but draws the wrong conclusion from that fact.
The fact is that Nakamichi decks DO have excellent high frequency response.
This is the very reason why you can use good tape with them, since they can
take advantage of the performance advantages of first-class tape.  Using first-
rate tape with an economy deck is a waste of money, since the low end deck can
not extract the performance from the good tape.  What the good tape buys is
more headroom at higher frequencies (which is especially important if you are
using Dolby C for noise reduction, and is not as critical if you use dbx)
where tapes tend to saturate at a lower level.
The key thing is to match the tape's bias requirements to that provided by
your deck - if your deck is adjustable, you have considerable leeway here, but
if it isn't you have to use the tape the factory adjusted the deck for or
get a service tech to adjust it for your pet tape. 
Nak decks are set up for Nak tape at the factory (which isn't that easy to get
and generally isn't discounted).  However, magazine test reports have indicated
that Maxell UDXL-I (or XL-I as it is now called, not to be confused with XL-IS)
has similar bias requirements to Nak EX (Type I - Ferric); TDK SA-X is similar
to Nak SX (Type II - Chrome or chrome like tapes); and TDK MA is similar to
Nak ZX (Type IV - metal).  Of course formulations change all the time so you
should keep up on magazine tape test reports to see how the current formulae
compare to the one your deck is set up for.
Which tape should you use?
Type IV (Metal) is the most expensive and is generally only needed for material
with very wide dynamic range, like live recording and dubbing audiophile
LP's and CD's.
Type II (Chrome and its kin) is my favorite for general album dubbing and
off the air copies - Personally I use Maxell XL-IIS (and had my Nak 680ZX
set up for it when it was in the shop), and it is heavily discounted in the
NYC area.  You can save some money by using XL-II (no S) for lower quality
(such as the general run-of-the mill pop recording) material.
Type I (Ferric) is needed if the deck (like some car decks) you're going to
play it on doesn't have the 70us EQ needed for type II or IV tapes.  The best
Type I tapes (like Maxell XL-IS) are comparable to the best Type II's except
that the II's are a bit quieter.  Again, you can save some money by using
XL-I for lower quality material.
Whatever you do, stick to name brand tapes (like Maxell, TDK, BASF, or Scotch)
Unknown brands tend to have low sound quality and mechanical problems.
2.  The March 1984 "Stereo Review" has two articles of interest - the first
describes the operation of the three tape noise reduction systems (Dolby B,
Dolby C, and dbx) while the second gives more information on how to choose the
best type of tape for your needs.
3.  All tape decks do require demagnetization from time to time (generally
every 50 hours is a good rule - the 10 hour figure is for CLEANING and should
be followed for that purpose).  Nak decks are less prone to head magnetization
that most others and don't have to be demagnetized as often as every 50 hours.
Once a year may not be often enough, depending on how often you use the deck.
Demagnetization can do no harm if done too often, PROVIDED IT IS DONE PROPERLY.
BE SURE TO TAKE THE DEMAGNETIZER AWAY FROM THE DECK SLOWLY AND NOT TO TURN IT
OFF UNTIL YOU ARE FAR AWAY FROM THE DECK.
You can use one of the cassete-size automatic units (like TDK's) but keep in
mind that it only demagnetizes the heads and not the other metal parts in the
transport (like the capstans) which can also become magnetized during operation
4.  In response to the medium-priced tape deck query:-
By all means get a Nak BX-1 or BX-2.  You'll spend your money where it counts,
on performance and not on a lot of fancy features.
Regards,
Bill Mitchell
Bell Communications Research Inc.
Whippany, NJ  (whuxj!wjm)