TEAC Unknown Owners manual

5IOI33T I

The purpose of this booklet is to supply a fund of information that will increase your knowledge of and interest in open reel
tape decks. We realize that no manual this size could possibly answer every question you may have nor cover every feature and
technique used today. But, if this booklet helps you to enjoy your deck a little more, its basic purpose has been achieved.

-CONTENTS-

page 2 Tape Tracks and Channels on O pen Reel Tape Decks

3 Introduction to Open Reel Tape Decks

4 Introduction (Part 2)

5 Bias and Equalization — General Theory

6 Quadraphonic So und and 4-Channel Tape Decks

7 The Tape - Record Time vs Length

8 Tape— Judging Condition and Handling

9 Special Recording Techniques

10

11 About Dolby NR

12 Timer and Remote Control

13 Owner's Care

14 Basic Trouble-shooting Ch art

15 Tape Loading and Erasing

16 Lubrication and Optional Accessories

Special Recording Techniques (part 2)

ENVIRONMENTAL CONSIDERATIONS

Your TEAC deck is well constructed and is adaptable to a wide range of conditions, but a few cautions should be observed to insure proper
operation and prolong unit's useful life.
TEMPERATURE EXTREMES
Do not operate the deck at temperatures above 100/F (38/C) or lower than 40/F (5/C). Direct sunlight, stoves, or heating devices nearby will
also raise the internal temperature of the deck which may cause damage to some components. Low temperatures may cause sluggish
operation and place an overload on the drive mechanism.
DUSTY ENVIRO NMENTS
As with any precision machine having moving parts, your deck should be covered when not in use. Excessive dust may result in bearing or
tape head wear. Also protect yourtapes from dust.
HIGH H UMIDITY AND OCEAN SA LT AIR
High humidity conditions will shorten equipment life from corrosion and possible fungus growth on the printed circuit boards. If near the
ocean, extra care should be taken to cover your deck after use. Covering will prevent salt air from corroding metal surfaces, especially the
bearings and internal connections.
EXTREME LINE VOLTAGE FLUCTUATION
If you are in an area where line voltage fluctuation is severe, the use of a voltage controller (VARIAC) may be advisable.

Tape Tracks and Channels of The Open Reel Tape

Decks

1. Full track recording: The magnetic flux pattern produced by the head covers almost the whole surface of the tape. The entire tape

is recorded in one direc tion only.

2. Half track monophon ic: The flux pattern generated by the head covers less than half of the tape surface and the recording head is
off-set to one edge of the tape. A monophonic signal is recorded on one half of the tape and then the reels are inter-changed and the
other half of the ta pe is record ed. The sam e half track head is used for both passes. T he tracks are, o f course, reco rded in opp osite
directions on the tape.

3. Half track stereo: Two recording sections (heads) are used to record two tracks simultaneously on the tape. Both channels are
recorded in the same direction on one pass through the tape.

4. Quarter track, 2-channel stereo: 2 record heads are used to record all 4 tracks on the tape. On the first pass through the tape, track
1 and 3 are recorded simultaneously. At the end of the first pass, the reels are inter-changed and tracks 2 and 4 are recorded using the
same two he ads that reco rded tracks 1 and 3. Th e actual prog ram on the tap e for tracks 1 an d 3, and 2 and 4 is reco rded in opp osite
directions but since the reels are inter-changed between passes, the tape is recorded and played in the forward direction for both passes
of the tape.

5. Quarter track, 4-track/4-channel (Qua draphonic): The head assembly consists of 4 separate heads and all 4 tracks can be
recorded at the same time on a single pass through the tape.

6. Quarter track, single channel (Mo nophonic): The 4 tracks on the tape are recorded one track at a time. At the end of each pa ss
through the tape the reels are interchanged and the next track is recorded. The order in which the tracks are recorded is 1, 4, 3 and 2.
Four track re cording gives maximum playback time however, the benefits of stereo reproduc tion are lost.

DIAGRAM A.

Playback compatibility

Diagram A shows the relative track locations and dimensions on a standard prerecorded 1/4" open reel tape. The playback heads
closely correspond to the record heads depicted in the diagram. Some decks in fact use the same record head for playback also. A brief
study of the track locations and recording sequence for the various common tape formats will lead to many valid conclusions
concerning compatibility between various tapes and tape decks. Some of these conclusions are stated briefly below.

1. A half track mono deck can playback a pre-recorded full track tape.

2. A half track stereo deck can play either a full track or a half track tape but the signal from a half track mono tape on side 2
will be played b ack in the op posite direc tion. However, the right channel output can be turned down and the left channel only
used for playback of both sides of the tape. When playing a furl track tape the left and right channel will reproduce the same
sounds.

3. A four track stereo tape dec k can playback both 4 track and 2 track tapes and from the point of compatibility has the widest
possible range of utilization. When playing a 2 track stereo tape on a 4 track recorder, track #1 will be completely covered by
the head. Track #2 will be slightly off alignment but stereo can still be enjoyed by compensating for the slight loss of track #2
volume with the volume or balance controls of the amplifier. On the other hand a four track tape cannot be played back on a
two track reco rder as bo th tracks #1 a nd #2, and #3 and # 4 will be repro duced together resulting in m ixed unintelligible
sound.

There are of course other possibilities for playback compatibility that the inventive audiophile or home recordist can discover by
consulting this diagram and o ther sour ces. The pr ocedures fo r rec ording in each of the v ario us formats will be covered in the O wner 's
Manual supplied with each TEAC deck. T his section is intended to give the interested recordist a complete overview of standard
recording tape forma ts.
Almost all tape decks are designed and constructed to record and playback only one of the standard formats. A few 4-channel decks
have a selectible 2-track playback head for compatibility with pre-recorded 2-track tapes. Full track and half track monophonic decks
for home use are rarely, if ever, available today. Full track professional decks may be purchased however.

Introduction to Open Reel Tape Decks

Open Reel

Many articles have been written concerning the relative merits of open reel decks vs cassettes decks. Some of these articles have even
selected one or the other as being better. Our position, at TEAC, is that both types are excellent, can give good service and provide
many months and even years of recording and listening pleasure. A large number of audiophiles own both an open reel deck and a
cassette deck. Cassette decks have many advantages and features that continue to attract customers (especially convenience and price).
Open reel decks also have capabilities and features that appeal to many serious audiophiles. Here are some of them. Features such as
separate Record/Playback heads, Editing and cueing controls, mic-line mixing, monitoring functions, provide versatility for many
creative recording situations. The modern audiophile doesn't seem to be content to just record performances as they are. He or she
wants to create, to experiment, to modify. They want to put something of themselves into their recordings. The pro or semi-pro
recordist will find the high end performance and versatility a distinct advantage. Few, if any, records are made today directly from a
single live performance. A singer's voice is recorded at one time, instruments are added or changed, a chorus may be added and often
other special effects are mixed in. The final recording may be completely unrecognizable by the artist who sang the original song.
The higher speeds of the open reel decks make possible higher quality recordings which challenge the limits of one's entire stereo
system.
The quality, styling and price of open reel decks make them prestige items. A well designed open reel deck seems to blend in with the
most expensive furniture decor and even enhances the overall atmosphere of successful living. There are various head types and
configurations. Thi s sec tion is intend ed to give you a ba sic idea of ho w some o f the systems oper ate. Ple ase c onsult y our o wner's
manual for complete details of the features and capabilities of your deck.

Earlier models of tape recorders used a combined Record/ Play head.
(Diagram A). With such a head, you cannot record and reproduce at the
same time. Another disadvantage of the combined head was in the design
of the width of the head gap. Modern head technology generally dictates
that the gap width should be different between the record and playback
functions for optimum output and frequency response.
When there are severe space and cost limitations, combined record/play
heads are still used today, and even though these heads are well designed
and highly efficient they still represent a compromise of optimum head
design. Open reel decks which normally have no head space limitations
and usually command a higher price due to their special cap abilities,
normally have separate R ecord and Play head s. (Diagram B). The sep arate
heads allow monitoring of the tape during recording. This system has
distinct advantages. You can insure that your tape is actually being
recorded properly as you record. The playback signal can also be
connected to the record head for special effects, such as sound-on-sound,
echo and sound-with-sound. (These techniques are explained on pp. 9,

10.)

With separate record and playback heads there will be a time delay
between the recorded signal and the reproduced signal. The delay depends
on two factors; the physical distance between the two heads and the tape
speed. For instance, if the record head and playback heads are 1-7/8" apart
and the tape speed is 3-3/4 ips, the delay is about 1/2 second. With the
tape speed increased to 7-1/2 ips; the delay is 1/4 second. At 15 ips the
delay is about 1/8 second. See diagram B.
For some recording situations, even this fraction of a second is not
acceptab le. If a musician or audiophile
wanted to add a new instrument or voice to a song already recorded and
wanted to listen to the record ed song for tim ing and synchro nization, this
delay would present a problem.

Introduction to Open Reel Tape Decks (cont)

Editing and Cueing

Editing means to change a tape by physically cutting out unwanted sections of a recording or adding sounds by adding pieces of pre­recorded tape. The cutting and rejoining of sections of tape is called splicing. Cueing means to locate a section of tape by listening for
the beginning or end of a rec orded section. High speed cueing is done by causing the tape to contact the playback head during fast
forward or rewind operation by retracting the tape "lifters." Manual cueing is done by moving the tape across the playback head by
turning the tape reels by hand. High speed and manual cueing are special features that are available on most TEAC open reel tape
decks.

MIC/Line Mixing

MIC/LINE mixing is a feature that allows the recordist to mix a line input and a microphone input together on the same track. An
internal mixer in the tape deck is required to accomplish this. You can add a live sound by MIC (your own voice or other sounds) to a
pre-recorded song connected to the LINE Inputs for real creative recording.

Monitoring function

Monitoring basically means to listen to the playback of a recording while recording. You can insure that the sound is actually going on
the tape properly without waiting until the tape is rewound and then played back. The deck must have separate REC and Play heads for
this monitoring function.

Splicing Tape

Editing tape is a fascinating way to make creative recordings by eliminating and joining different segments of a recording into one
pleasing tap e. Long, silent or boring segments can be rem oved by p roper editing. In fact, as editing is a creative exercise, the re is only
your imagination and the length of tape to limit the possibilities. Broken tape can also be easily mended by splicing, one of the steps
required in editing.
The first step is to precisely locate the section of tape to be removed.
On some TEAC decks this can be done by manually cueing the tape. Consult the Owner's Manual for operation of this feature in your
deck.
Next, use an Editing Block or a pair of scissors (demagnetized) to cut the tape at the places marked. Finally, the splicing is to be done.
A Tape Splicer is preferred, but a pair of scissors that have been demagnetized will be satisfactory. Before you proceed, have some
commercially available Splicing Tape available. Never use Cellophane (Scotch Brand) tape, for that adhesive will spread and
contaminate your head s.

1. Overlap the ends to be spliced by approximately ½ inch and align

them carefully.

2. Cut through the center of the overlapped area at a 45 to 60 degree

angle.

3. Butt the slanted ends of the cut tape together. Use a straightedge or

ruler to assure a perfectly straight alignment.

4. Apply splicing tape to the shiny base side of the tape (opposite to the

tape side that touches the head) as shown in diagram 2. Note that
splicing tape goes perpendicular to the recording tape.

5. Place the spliced connection on a hard surface and rub the splicing

tape briskly with your fingernail or o ther hard sm ooth object. This is to
assure a firm adherence to the splicing tape.

6. Trim off the excess splicing tape as shown in Fig. 3-1 and 3-2. Note

how to cut slightly into the recording tape to insure complete removal of
the excess.

IMPO RTANT: Editing will destroy or seriously "cut" any material recorded on the other side of the tape (tracks 2 & 4). If editing is
anticipated, record only on one side of the tape. After editing, material can then be copied onto both sides of another tape. When
attaching blank "leader" tape onto your tapes, follow the same procedures given here for splicing.

Bias and Equalization-General Theory

Bias

In order to get the magnetic particles on a tape to respond properly to the changing signal supplied to the record head, a pre­conditioning bias is needed. Most home recorders today use an alternating current (AC) bias at a frequency of 50 to 150kHz. This bias
raises the magn etic level of the o xide particles so that even small changes in the signal from the record head will cause relatively
similar changes in the magnetic level of the particles on the tape. Without this bias pre-conditioning, the oxide particles do not respond
properly to the signal from the record head. This high frequency bias signal is applied to the tape together with the desired audio signal
by the record head. Since the bias signal frequency is much higher than the audio frequency range, there is little chance that the bias
signal will interfere with the sound reproduction.
The amount of bias (bias level) affects the signal-to-noise ratio, distortion and the frequency response of the tape and hence of the deck
itself. Too little bias w ill allow more d istortion than is ne cessary. Bias also affects the output lev el of the tape. N ormally, as bias is
increased the signal level off the tape increases, up to a maximum output level which depends on the type and quality of the tape.
Increasing the bias level beyond this point causes the output level (and consequently, the S/N ratio) to decrease. The "optimum" level
of bias is usually a c omprom ise between the best results in S/N ratio, distortion and high frequency response, and usually differs with
different types and brands of tape. For this reason, all TEAC tape decks offer the user a switch selection for different bias levels or a
bias adjustment. One or the other of these is absolutely necessary if the recordist expects to use more than one type of tape. If everyone
used the same type and brand of tape, the tape deck manufacturers could all set their bias circuits for a specific type of tape and
everything would be fine. But, there are many good brands and types of tapes available and many recordists use more than one type of
tape. Experience and e xperimentation will help you decide which tape to use and what bias level is m ost appro priate
for specific situations.
TEAC offers charts and/or instructions on how to set the bias level for various brands of tape. These instructions should be followed
until the recordist developes sufficient knowledg e (and has the proper m easuring equipment) to make reliable tape evaluations.

Equalization

The EQ (equalization) selection must also match the type of tape formulation being used. If for instance, a deck was factory adjusted
for standard tapes and the recordist decided to use low noise/high output tapes with their accompanying high frequency emphasis, the
high frequencies would so und too bright.
The equ alization switch c an be used to reduce this high frequency over-emphasis an d restore the o utput signal to its orig inal fidelity.
Conversely, if the deck is factory adjusted for low noise/high output tapes and the recordist decided to use standard tapes, the high
frequencies will be much lower and an equalization setting that emphasizes high frequencies should be selected to compensate for
these low levels. TEAC tells in our instruction manual what equalization level should be selected for various types of tape. Together
with the bias setting, the suggestions sho uld be close ly adhered to until the audiophile develop es the experience and knowledge to
decide for himself.

Frequency Response

Frequency response is one of many parameters or specifications that manufacturers consider in the design of their open reel tape
decks. But it is possible to over-emp hasize this one parameter at the exp ense of others, such as signal to-noise ratio. In general, it's best
to consider a well designed tape deck as a series of compromises that are made to give the best overall operation and performance. The
following musical sound frequency chart will help you understand the basic requirements of frequency response versus actual
recordable freque ncies.