Fostex 350 - INTERCONNECTIONS AND INSTALLATION; CONNECTING THE INPUTS; CONNECTING THE OUTPUTS

SECTION 2 INTRODUCTION
The Fostex 350 mixer is a versatile 8x4x2 mixer designed
for recording, production and P.A. applications, utilizing the
popular unbalanced input/output format. It incorporates the
latest in electronic technology and offers many new concepts
in terms of operation and layout.
Each input section utilizes a peak indicating L.E.D. which pro¬
vides an obvious warning of approaching overload. The mixer
also facilitates an optional meter bridge for monitoring ex¬
plicit levels of all output busses where necessary.
When the 350 is used with the Fostex A-Series open-reel
recorder-reproducers, the L.E.D.'s and the recorder’s meters
will suffice in most applications.
The organization of the 350 provides some particularly con¬
venient functions such as switching from multitrack record to
mixdown without repatching, stereo monitoring, and two
stereo headphone jacks. Control layout is essentially the
same as signal flow, and parametric type equalization on
each of the 8 inputs provides a broad range of effects and
“sweetening”. Eight separate accessory send and receive
circuits provides additional flexibility in all applications.
Fostex’s engineers, who pioneered the development of per¬
sonal multitrack and mixing equipment, designed the 350 to
meet the needs of the serious small studio or production
facility as well as stage and P.A. users. It combines ease of
operation, reliability and flexibility in an extremely compact
package, and is particularly compatible with multitrack equip¬
ment such as the Fostex 8 track, 1/4” recorder Model A-8.
Your 350 should provide years of top audio performance with
a minimum of service, using reasonable care.
HOW TO USE THIS MANUAL
While it may be possible to “get by” without reading this
manual, the utmost in creative results can only be obtained
when one is thoroughly acquainted with the 350 and its full
capabilities. We suggest quickly reading this manual once
before using the 350, then re-reading the manual later, after
becoming familiar with the basic functions of the mixer.
Section 1 contains brief descriptions of each feature and con¬
trol. This is handy for quick references, although for a more
detailed step-by-step guide to connection and use, consult
Section 3. The remainder of the manual will illustrate in more
detail, the use of external processing equipment, the
equalizers, and examples of mixing for multitrack, produc¬
tion, and P.A. Then, most important, study and refer to the
block diagram in Section 11. You will find this to be an impor¬
tant aid when reading the use and applications sections of
this manual, as well as providing you with more intimate
understanding of the 350 and its potential.
SECTION 3 INTERCONNECTIONS AND INSTALLATION
Whatever the application, certain procedures should be
followed for setting the mixer up for use.
The power cord of the mixer should be connected to an AC
supply of the correct voltage.
While the outputs of the Model 350 incorporate a circuit to
prevent an audible power on “thump”, it is always advisable
to turn the power on to amplifiers or tape recorders con¬
nected to the outputs of the mixer AFTER the mixer has been
switched on.
CONNECTING THE INPUTS.
The input circuits of the Model 350 are such that they may
accomodate an extremely wide range of input signals. You
may connect virtually any signal, ranging from microphone to
tape recorder level, directly to the input jack.
While the circuit design accepts both the direct output of
electric instruments and microphones, it is advisable to use a
matching transformer such as the Fostex Model 1030 when
using low impedance microphones over long runs or via a
multi-conductor cable. Not only does this provide a degree of
extra noiseless gain, but also reduces pickup of induced
hums, buzzes and RFI.
NOTE: Never connect any signal output rated in "Watts"
to any input of the model 350. These are often high voltage
signals ordinarily Intended for loudspeakers. If you need to
make such a connection use a “Direct Injection" or “ Dl"
box, or direct box obtainable from your dealer. Failure to do
this may result in damage to the circuits of the Model 350,
and/or the power amplifier.
To set the input trim, adjust this control on maximum signal
peaks until the LED above the corresponding fader just
ceases to flash. This will be the optimum input level. Should
the signal level rise, the LED will start to flash again, giving
you clear indication that you should reduce the setting of the
trim control again. “Tape in” (18)and “buss in” (21), accept a
- lOdBV(0.3V) level.This is compatible with all Fostex record¬
ing equipment and most other musicians’ studio equipment.
These inputs will also accept a nominal level of OdBm, which
are standards in many professional studios, though the over¬
load headroom will be somewhat lower.
Remember, as long as your input LED is not flashing, you are
not overloading any of the input amplifiers. If required you
can include a simple input attenuator in line with your input
signal. If in doubt consult your dealer.
CONNECTING THE OUTPUTS.
All outputs are at a nominal - lOdBV (0-3V) level. This
signal level is compatible with all Fostex recording equipment
and most other musician’s studio equipment.
While you may find that certain recorders, amplifiers or signal
processors are specified with a nominal “OdBm” or “OdBV”
level, these often have a front panel input control or pre-set
which will readily accomodate this - lOdBV level.
It is important to set the input level control on equipment con¬
nected to the mixer outputs, to an optimum setting to achieve
the best minimum noise, and maximum overload perform¬
ance.
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