Audio Technica AT705 User manual

OWNER'S MANUAL

Your new AT705 stereo headphone consists of a lightweight,
comfortable headphone and a separate impedance matching
adapter which connects to the amplifier output of your stereo
system.
The technical expertise
and manufacturing skill of Audio-
Technica, makers of the highly acclaimed Dual Magnet phono
cartridges, were fully exploited to bring you this excellent head-
phone set
featuring a wide-range flat response and clear, nat-
ural sound.
As with our other headphone models, the functionally sen-
sible bi-polar, open- back
construction was applied to this head-
phone. This design not only reduces weight and bulk but also
improves
transient response and eliminates the "closed- in" feel-
ing which is a cause of discomfort when using the convention -
ai, closed-back headphone.
The convenient impedance
matching adapter does not re-
quire a separate power source, thus eliminating the usual cause
of static and possible damage to the driver units. Simply hook
it up to your stereo amplifier and you are ready for an expe-
rience in superb music enjoyment.
YOUR AMPLIFIER
The adapter can be connected to any ampli-
fier with an output of over 3 watts and de-
signed
for use with 4 to 16-ohm speakers,
either
transistor or tube type , or even a pro-
fessional BTL model. Since the AT705 is a
CONNECTIONS
highly sensitive instrument , your amplifier
should be of a comparable high quality with
low distortion and noise levels. The adapter
should be connected to the speaker terminals
of the amplifier, not the headphone terminals.
The connecting cords
of the adapter are color-
coded as
follows:
Red : R+ (right channel)
Black: R-
(right ground)
White: L + (left channel)
Blue: L -
(left ground)
1. After switching off the power supply of
your amplifier, remove the speaker cords from
the terminals and connect the adapter cords
as illustrated below(Fig . 1). In some ampli-
fier models the channel terminals may be
marked "8 ohms" and the ground terminals
as "0" or " Common." In the case of a tube
model where the plus terminals are separated
into 4-ohm, 8-ohm and 16-ohm, test-listen
using each terminal and select the best one.
Generally speaking, the
finest effect is ob-
tained
through the 16-ohm terminal.
2. Next, connect the speaker cords to the ter-
minals on the back of the AT705 adapter as
shown in Fig.1. Be sure that there are no
loose
wires which can cause short circuiting ,
then
tighten the screws.
3. If your amplifier has an extra pair of speak-
er terminals , simply connect the adapter input
cords to them and leave the speaker connec-
tions intact. Operating the stereophone-
speaker
switch of the adapter will channel
the signal
to the respective equipment.
4. Finally, insert the headphone cord plug
into the jack of the adapter. The dent in the
plug casing should face upward . This com-
petes the necessary connections.
LEFT CHANNEL SPEAKER RIGHT
CHANNEL SPEAKER
AMPLIFIER SPEAKER TERMINALS
+
Fig.1

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....
.
AEDfWHJTE Il L
1' : --
:
. ~ .
. ~ ,
i: t~~~'
-
0 ','
II
,
AM P UFlER ~ __ 7-----*_-' ~~~~E ~S
BLAC lC/ BlUE...,---
I
-Ii -
I'l
ii
-
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..
-
Fig . 2 ADAPTER CIRCUIT DIAGRAM Fig.3 FREOUENCY RESPONSE CURVE (B&K)
OPERATION
1. First, be sure that
the amplifier volume
is squelched
to min·
~,~- ..
imum level since a .
.. .. -
sudden
input of ex·
cessive power can iiI_'
:"- _ ....
U •
damage the driver
units of the headphone.
2. Adjust the headphone so that the earpads
rest
snugly over your ears. Space between the
EARPADS
pads and your ears will cause adverse effects
at low frequency response.
3. When the adapter
switch is flipped to
"Stereophones" position the circuit to the
headphone will be completed. Switch on the
amplifier and gradually raise the volume to
the optimum level. Switching from phones to
speakers or vice versa should always be done
with the amplifier volume at minimum level.
The earpads used
on the AT705 are
designed and
con·
structed to comple·
ment
the fine per·
formance
of the
equipment.
They can
be detached for cleaning by firmly
holding the frame and slightly turning clock·
ADDITIONAL NOTES
1. Since the AT705 will faithfully transmit
the performance characteristics of your audio
components,
it should be noted that the bet·
ter your equipment. better
will be the sound
quality you will hear through the headphone.
2. The input cord of the adapter may be
lengthened by connecting any available
SPECIFICATIONS AT705
speaker cord. However, the headphone cord
has
been selected with precise consideration
to the total capacitance and should not be
tampered with .
3. Please keep your headphone
away from
heat. direct s unlight and mois ture at all times
to ensure long, satisfactory performance.
HEADPHONE
Type: Electret Condenser
Sensitivity: 98dS ±
2dS/SPL at 1kHz/ 100V
, ( OdS ~0.0002 microbar /V)
Max .Sound Pressure Level: 110dS SPL
Frequency Response: 10-25,000Hz ±3 dB
Total Capacitance: 1
OOPF (incl. cord)
Weight:
250 grams (excl. cord)
Cord Length: 1.9 meters
REPLACEMENT EARPADS : Aud io-Technica Hp·15
wise till a " click" is heard. Wipe with a clean
cloth dampened
with a mild detergent and
dry before remounting.
If the foam cushion inside the pad has
deteriorated due
to some reason, replace the
entire earpad with a genuine Audio ·Technica
replacement earpad, model HP15, available
from your dealer.
ADAPTER
Primary Impedance: 4·16 ohms
Step-up Ratio:
36dS
Distortion:
under 0.3%/lkHz
Rated Input:
l.4V RMS
Ma x. Input: 5V RMS
Cord Length : 1.3 meters
Dimensions: H45 x
W77 x D85mm
(exel. terminals & switch)
Weight:
570 grams
• Specifications are subject to change witho ut n 01ice.

audio-technica
AUDIO.TECHNICA CORP .• 2206 Naruse .- Machida. Tokyo 194. Japan