Tandberg 9000 X Review 3

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REPRI NTED FROM STEREO REVIEW AUGUST 1973

Tandberg 9000X Stereo Tape Deck

OTIItT-rls-gnnntehasloagbeenauoeiawdwith
sinde-raotor tape decks. but the companys new Model
sonox departs from tuition by m a three-motor
tr-sponlhalhuauninuea-lhidtlysophisticotnd hie-
graied-circuit th) lode control system. Tn; mx 3; u
three-speed (7ls. J'la. and Flu ipsl machine with separate
record and playback heads (and preampsl that permit oll~
the-tape monitoring. Like the other Tandbet-g recorders.
thisoneuoesasepanlecrou-leldheodloapplythen-
cordir bias to the tape. With this Indiana". rehtively
little high-frequency boost in the ncording qralintion is
nece-ry lolly 6 db at 20.0.10 H1 and 7'/- ipsl. This
means that there is a substant'nl improvement in record-
ing "Moons" before {anal mutation toverloadl oc-
curs. The capstan is driven by a hysteresis-synchronous
motor. and separate motors are used for the tape hubs.
which accept reels of up to 7 inches in diameter. A photo-
electric system stops and disengages the transport at the
end of a tape or at any point where a piece of clear leader
tape has been spliced into the reel,

In the rear of the 9000X are the line inputs and outputs
(and a DIN connector). Twin front-panel slider controls
set recording levels. and another pair adjusts the play-
back-output levels. Signals applied to the two front-panel
microphone jacks mix with the line inputs and share their
level controls: there is no provision for separate adjust-
ment of microphone levels. Microphones with rated im-
pedances of 200 to 700 ohms can be used. and "It "ll!
circuit autumtically adjusts the preamplifier characteris-
tics to suit the microphone impethaee. mat-iii. an
opt-nuns shal-to-noise ratio.

During recording. the two level meters read the input
recording levels. whether or not off-the-tape monitoring is
used. When the PLAV button is pressed the meters are
electrically switched to read the actual output levels un-
der the control of the playback-level sliders. Meter Ci!-
cuhs are desbned to have the salts mponse characteris-
tics» the equalized fed tothe tape head. This
mininiles the possirility ol tape saturation with high-fre-
mysiapahotthesortthtconvenmnalntaeridont

4R

respond to. In addition. the meters are last-actir'. read-
ing the signal peaks within «I to 50 niliseconds.

Below the meters are two red necolo interlock but-
tons. Two other buttons (labeled sown/rue) connect
the line outputs to the program source or to the playback
amplifiers. A small switch connects the playback from
either channel to the other channel's recording input for
making sound-on-stmnd or echo recordings. A head
phone jack drives stereo phones with impedances ranging
from 8 to 2.000 ohms.

The upper portion of the panel. finished in black like
the lower control section. contains the reel hubs. a green
pilot lamp for the power switch. and a four-digit index
counter. At midheight on the panel are the live halter-
touch purhbutton transport controls. the power switch.
and a tapeapeed selector lever.

accus-

The logic-controlled tape transport system is one ofthe
most fascinating features of the mmx. Fifteen integral.
ed circuits tequivaient to about seven hundred transis-
tors!) are devoted to this function. The user can switch
directly from any mode to any other. except that auvono
can only be engaged when the tape is stopped. For gum.
ple. during fast forward and rewind. pressing the rt AV
button stops the tape almost instantly. and in less than
tvto seconds the transport resumes operation at the se-
lected playing speed.

mono function will not operate unless one or
both olthe interlock buttons is engaged. Since its action rs
Virtually Instantaneous. there is no need for the separate
pause control found on most recorders Once the input
levels have been set. the 9000X is ready to record at the
touch or a single button. If the PLAV button is touched
while recording. the transport witches instantaneously
from record to play lifthe REIZOID button is pressed while
the tape is playing. nothing happens). Each button is illu-
minated in green texcept for the red att'ono button)
when activated; it is dark at all other times. TM f
design ot the 9000) transport. especially 0! its braking
system. is illustrator! by the {act that shuuit' o. the
power while the tape ll in fast forward or rewind brings
the machine to a smooth stop. with no tendency to spill or
break tape.

The Tandberg 9000K is mounted on an attractive
wooden base. and can be installed venically or horizon-
tally. Spring-Ioaded reel-lock hubs eliminate the need for

r(nnrinurd rm page 50!

SYEIkO IEVIF \"

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rubber reel holders during venical operation. lts panel
dimensions are Its'iu inches by I51": inches; the deck is 7
inches deep and weighs 54 pounds Price: $649 50. An
optional reinoiecontrol unit with special provisions to
facilitate use of ii timer costs $79.90, Dynamic micro-
phones are also available at $49.30 each. A carrying case
is $40. and a dust cover costs $12.

0 laboratory Measurements. The playback frequency
response of the Tandherg ltkKiX. user the full range iii
the Ampcr. lest tapes. was well within :2 dB from 50 to
7.500 MI ill I: ips. and from 50 to .000 H! at 7: ips.
The record-playback frequency response. nith the rec-
ommended Muell UDJS tape. was typical of Tandherx
machines :I 5d! from 10 to 25.500 H1 at 7% 'Ps. :2
dl lrom 3010 22.300 H1 at i ips. not :1 dllftom 41m
9500 H1 at I'I- ips.

An input 0! I I0 millivulis tlinel or 0.07 millivolt
[microphone inputs. 600-ohm source impedance) pm-
duced a O-VU recording level at |.()00 Hz The corre
sponding maximum playback output level was L9 volts.
These measurements were made in stereo; when only one
of the channel recording interlock buttons is depressed.
the gain is reduced by about 8 dB. Headphone listening
volume was good.

The meters ofthe Turdber' mx Ire peakdndtcatin'
destices that read either -8 or .. l l VU (depending on the
tape speed) [or levels that would produce a 0V1} reading
on conventional meters. As a result. the 3 per cent refer~
ence-dislortron pomt is ruched ll *2 VU on the meters
at 7ia ips We measured slightly over 2 per cent distor-
tion at Tandberg's 0~VU level at the two higher tape
speeds. and 4.3 per cent at the l'lyips speed. The 3 per
cent distortion level corresponded to +I.5 VU at 3% ips
and -2 VU at W. ips.

Referred to the .1 per cent distortion levels. the un-
weighted natal-limo: ratios were 70 on It 71/: ips. on
M! ll 3"". ips. and 57 dB at 1'!- ips. These are emollient
to the best fipns we have ever obtained on a consumer
tape machine The noise-level increase through the mi-
crophone inputs was not significant forany settings ofthe
recording-level controls likely to be used. The lam olihe
microphone preamplifiets increases as the source imped-
ance decreases. making the KKIDX a good choice for
matting live recordings with highquality. Inwampedance
microphones.

The wow was 0 025 per cent at the slowest tape speed
and 0.0! per cent tihe test tape residual) at the other

Thr rune limit! at Mr 9000X lJ ("ruled I0 Ihefur loll ofthr Iirud
rm: Thr man] tin-I ruin-field bin: hails-mu {mime iIir
.iilm-urr .lmei "but? the left recording-[rid mrlrr Thr
mm-dmr mrt'hunum ll drawn in lite dirrnuaped puiilum

speeds. unweighted flutter In: 0.075 per cent at 7V: ips.
0 to per cent at .i ips. and 0.17 per cent ll 17/. tps The
tape speed. as determined by a siroboscope iesi wheel.
was CHLI A LZOO-foot reel of tape ran through in fast
forward or rewind in 56 seconds.

0 Continent. The perfonnlnee of the Tan-fiber. 9000x
was as nearly ideal as any we have seen Not only was
there no audihle change in the sound of records or FM
hmudcasts when recorded and played hck ll 7% or H:
ips. but even "'pinli or random noise came throth utt-
rnodtfted This is an euremely severe lest. particularly of
a recorders dynamic range at the highest audio [requen-
cues. At ll. tps. lhe overall performance was quite close
to that of a lisp-quail!) casstlle MW". and [he SING
signal-Io-niiise who was comparable to that 0! I Dolby-
equipped cassette Machine.

Bet-misc at the special meter calibration and response
characteristics, recordings are made at a somewhat lower
Icicl than Itlh most tape recorders, With average rud-
ings tll .ihuui ltl \l . the fulldynamtc w otihe ritu-
chine ls reamed. and peaks to 0 VU or slihtly hicher
do not yulis( significant distortion

The transptin controls operated smoothly and thw-
Iessly during our tests and use 01 the recorder, and we had
no problems in adjusting to their characteristics except
for the close spacing (and identical size. shape. and color)
of the {our basic transport control buttons. Ouronly crili~
cism ta minor one) of the functional electrical design of
the 9000X relates to the lack of separate level controls for
the microphone and line inputs: If you wish to use the
mike inputs when the recorder is connected intoa music
system. it is necessary either to switch your amplifier to
an unused input or disconnect the recorder's line-input
plugs.

The iapcloading pllh is direct. essentially in a straight
line with a nude iensionin. arm adjacent to each reel.
(human-ted tape "1!th is not only possible. but prec-
iiciil The Tandher' mllix. which is priced only about
Slot) higher than the manufacturer's best lindeqrtotor
recorder. oflers equal or hetier electrical performance in
every respect. and essentially represents the convent state
at the art for consumer tape recorders

For more inform-tron. circle to: on reader service card

§TEIEO REVIEW