Fostex PH-50 User Manual

Headphone Amp Distributor

Model

PH-50

Owner's Manual

Thank you for purchasing our Fostex product.
The model PH-50 is a headphone distributor. It has three inputs and five high power (500mW) headphone
outputs whose output level can be separately controlled. In addition, it contains a matrix box function for
five inputs and five outputs.
For inputs to the headphone distributor, it has two balanced lines and one unbalanced line. The balanced
input level can be switched for receiving +4dBu or -10dBV levels. Also, the CUE box function can be
employed by using the AUX inputs, and the multi-channel operation by cascade connection of a multiple
number of PH-50's. Please carefully read through this manual for many years of good service.

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK,

DO NOT REMOVE COVER (OR BACK).

NO USER - SERVICEABLE PARTS INSIDE.

REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

CAUTION:

TO PREVENT ELECTRIC SHOCK, MATCH WIDE BLADE OF PLUG TO WIDE SLOT,
FULLY INSERT.

ATTENTION:

POUR EVITER LES CHOCS ELECTRIQUES, INTRODUIRE LA LAME LA PLUS
LARGE DE LA FICHE DANS LA BORNE CORRESPONDANTE DE LA PRISE ET
POUSSER JUSQU' AU FOND.

The lightning flash with arrowhead symbol, within an equilateral
triangle, is intended to alert the user to the presence of uninsulated
"dangerous voltage" within the product's enclosure that may be of
sufficient magnitude to constitute a risk of electric shock to persons.

"WARNING"

"TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK,
DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE."

SAFETY INSTRUCTIONS

1. Read Instructions - All the safety and operating instructions should be
read before the appliance is operated.

2. Retain Instructions - The safety and operating instructions should be
retained for future reference.

3. Heed Warnings - All warnings on the appliance and in the operating
instructions should be adhered to.

4. Follow Instructions - All operating and use instructions should be followed.

5. Water and Moisture - The appliance should not be used near water - for
example, near a bathtub, washbowl, kitchen sink, laundry tub, in a wet
basement, or near a swimming pool, and the like.

6. Carts and Stands - The appliance should be used only with a cart or
stand that is recommended by the manufacturer.

An appliance and cart combination should be moved with care. Quick
stops, excessive force, and uneven surfaces may cause the appliance
and cart combination to overturn.

7. Wall or Ceiling Mounting - The appliance should be mounted to a wall or
ceiling only as recommended by the manufacturer.

8. Ventilation - The appliance should be situated so that its location or position
dose not interfere with its proper ventilation. For example, the appliance
should not be situated on a bed, sofa, rug, or similar surface that may
block the ventilation openings; or, placed in a built-in installation, such as
a bookcase or cabinet that may impede the flow of air through the
ventilation openings.

The exclamation point within an equilateral triangle is intended to
alert the user to the presence of important operating and maintenance
(servicing) instructions in the literature accompanying the appliance.

9. Heat - The appliance should be situated away from heat sources such
as radiators, heat registers, stoves, or other appliances (including
amplifiers) that produce heat.

10. Power Sources - The appliance should be connected to a power supply
only of the type described in the operating instructions or as marked on
the appliance.

11. Grounding or Polarization - The precautions that should be taken so
that the grounding or polarization means of an appliance is not defeated.

12. Power Cord Protection - Power supply cords should be routed so that
they are not likely to be walked on or pinched by items placed upon or
against them, paying particular attention to cords at plugs, convenience
receptacles, and the point where they exit from the appliance.

13. Cleaning - The appliance should be cleaned only as recommended by
the manufacturer.

14. Nonuse Periods - The power cord of the appliance should be unplugged
from the outlet when left unused for a long period of time.

15. Object and Liquid Entry - Care should be taken so that objects do not
fall and liquids are not spilled into the enclosure through openings.

16. Damage Requiring Service - The appliance should be serviced by
qualified service personnel when:
A. The power supply cord or the plug has been damaged; or
B. Objects have fallen, or liquid has been spilled into the appliance; or
C. The appliance has been exposed to rain; or
D. The appliance does not appear to operate normally or exhibits a

marked change in performance; or

E. The appliance has been dropped, or the enclosure damaged.

17. Servicing - The user should not attempt to service the appliance beyond
that described in the operating instructions. All other servicing should
be referred to qualified service personnel.

Notes On Operation

1. Do not use headphones for long hours at high sound levels.

If the headphone is used under such condition, it could injure
your hearing. Also, be careful not to rapidly raise the output
control when using the headphone.
Please use good sense to protect your hearing.

2. Turn down all sound volume controls before switch on power.

Be sure to fully turn off all sound volume controls when switching
on/off power to the PH-50.

3. Retard the sound volume control when the headphone plug

is connected or disconnected from the jack.

Always turn down the sound volume control before the
headphone is plugged or unplugged to the PHONES jack. If it is
plugged or unplugged while the volume control is set too high,
it could create noise and have hurt your ears.

4. Switch off power when connecting external equipment to

PH-50.

Always switch off power to the PH-50 when connecting external
equipment to it.

Names and Functions of the Controls and Jacks

Front Panel

5

1

100

5

100

5

3

PHONES

5

100

4521

7

1. Headphone output level control knob [PHONES 1 ~ 5]

For adjusting sound volume of the headphone plugged into PHONES jack
1 ~ 5.

2. AUX input level control knob [AUX IN]

This adjusts the input level of the external equipment connected to the
rear panel AUX IN jacks. The signal, whose level is adjusted by this knob,
is mixed with the signal whose level is adjusted by the INPUT knob and
thus output from both the PHONES jack and CASCADE OUT jack.

3. Peak LED [PEAK]

This will light when input is overloaded.
Should this light frequently, turn down the INPUT knob.

4. Power switch [POWER]

This switches on/off power to this equipment (LED will light at ON).
When switching on/off power to this equipment, turn down the level
control knobs on this and also on the external equipment.

12345

CHANNEL IN

(-10dBV)

8

2

5

100

100

5

AUX IN

3

PH-50

HEADPHONE AMP DISTRIBUTOR

100

PEAK

5

POWER

CAL

4

MONOST

6

5. Input master level control knob [INPUT]

Adjusts the input signal level of equipment connected to the rear panel
balanced input connectors (XLR or PHONE) or the unbalanced input jacks.
Standard input level is obtained when the knob is set to CAL.

6. Input image position selector switch [ST/MONO]

Image position, of input signals from equipment connected to the rear
panel balanced input connectors (XLR or PHONE) or the unbalanced input
jacks (RCA), is selected by this switch. If switched to ST, the input signal
will be output from the PHONES output jack or the CASCADE OUT jack, in
stereo if switched to ST, or in monaural if switched to MONO.

7. Headphone jacks [PHONES 1 ~ 5]

Headphones are plugged in here. Sound volume for each are adjusted
by the headphone output level control knob located above each jack.

INPUT

LR

100

INPUT

5

(+4dBu/-10dBV)

Rear Panel

PHONEXLR

HOT

T2

COLD

RS3

GND

1

RL

9

LR

(-10dBV)

CASCADE OUT

13

L R L/MONO R

(-10dBV)

INPUT AUX IN

12

(-10dBV)

11

8. Channel input jacks [CHANNEL IN 1 ~ 5] (RCA: -10dBV)

These jacks are used to directly assign external signals (monaural) to
each headphone output. Signal input to these jacks will not be affected
by the INPUT knob.

9. Balanced input connector [INPUT] (XLR, PHONE: -10dBV/+4dBu)

The balanced line is connected here. Two types of connectors XLR-3-31
and PHONE - are provided. Input level is adjusted with the INPUT knob
and the +4dBu/-10dBV switch is set to match the output level of the
equipment connected here.

10. Balanced input level selector switch [+4dBu/-10dBV]

When using the balanced input, this is switched to match the output
level of the equipment that is connected. The input level can be selected
for -10dBV or +4dBu.

+4dBu -10dBV

10

11. AUX input jack [AUX IN] (RCA: -10dBV)

This is a spare input jack. For an external equipment of monaural output,
it must be connected to L/MONO (the same signal will also be applied to
R). Signals input here are adjusted in level by the AUX IN knob.

12. Unbalanced input jack [INPUT] (RCA: -10dBV)

Unbalanced outputs are connected here. In the same way as for balanced
inputs, the input level is adjusted with the INPUT knob. When making a
cascade connection, this is connected to CASCADE OUT of the other PH-

50.

13. Cascade output jack [CASCADE OUT] (RCA: -10dBV)

When using PH-50 in the cascade connection, this jack is connected to
the unbalanced input jack of the next PH-50. This output can also be
used for recording by applying it to the INPUT of a recorder.