Sony ta 3200 f brochure

Page 1

Monufocluurs Specific-flout:

IHF Power (Total): 320 watts. B-ohm load:
500 watt, 4-ohm load. RMS Power per
Channel: 110 watts. e-ohm load: 130
watts, 4-ohm load. THD: Less than 0.1%
at rated output; less than 0.05% at 1 watt.
IM Distortion: Less than 0.1% at rated
output: less than 0.03% at 1 watt. Fro.
quency Response: 5 Hz to 200 kHz, +0.
~2 dB. IHF Power Bandwidth: 5 Hz to 35
kHz. S/N Ratio: 110 dB below full power
output. short oircuited input. Damping
Factor: 170 at 8 ohms, 1 kHz. Input Sensi-
tivity: 1.4 volts. input Impedance: 75 k
ohms. Dimensions: 15% in. w x 57/5 in. h
x 12% in. (1. Suggested retail price:
$349.50 (optional walnut case extray

Its been just about two years since
we reviewed Sony's preamplifier-control
chassis. Model TA-2000 (Auoio. Dec. 68).
At that time we (and Sony) would have
had to recommend a competitor's power
amplifier as the only worthy companion
to this magnificent preamplifier. With the
introduction of the TA-3200F Stereo Am-
plifier the people at Sony need no longer
be put in that embarrassing position, for
this new "powerhouse" is Ideally sulted
for use with that. or any other high-quality
prolessional or semi-professional control
chassis. While strictly speaking. the T/-
3200F is a "basic" power amplifier. it
does otter some of the flexibility at an
integrated amplitier. as can be seen by
examining the front panel layout shown
in the photo of Fig. 1. At the lower left of
this solid gold-anodized extruded front
panel is a lever-type power on/ofl switch
and an indicator light. A rotary speaker
selector switch follows. with positions
for main." "remote." "both." or no
speaker systems. With no headphone
jack supplied on the TA-3200F. one might
wonder why there is an "oil" position on
the speaker switch. Sony chose to omit a
headphone lack because the preamplifier
mentioned earlier (TA-2000) is equipped
with one and when it Is used It is desir-
able to turn oft all speaker systems. This
makes sense in any case. since most
users of basic power amplifiers often
mount this component in out-of-the-way
inaccessible places. whereas a preamplir
tier-control chassis. as the name Implles.
is always accessible and is the right
place for a headphone jack in such com-
ponent installations. Because of the tra-
mendous power handling capacity of the
TA-SZOOF. Sony wisely incorporated a
power-limiter switch with settings for 100
walls, 50 watts. and 25 walls This inno-
vation is intended for speaker protection
and limits the maximum power per chan-

As reprinted from the November
1970 issue of AUDIO magazine.

Sony Model
TA- 3200F

Stereo Amplifier

Page 2

Maul-cure?- Specifications:

IHF Power (Total): 320 watts. 8-ohm load;
500 watt. A-ohm load. RMS Power per
Channel: 110 walls, B-ohm load; 130
watts. 4-ohm load. THD: Less than 0.1%
at rated output; less than 0.05% at 1 watt.
IM Distortion: Less than 0.1% at rated
output: less than 0.03% at 1 watt. Fre-
quency Response: 5 Hz to 200 kHz. +0,
-2 dB. [HF Power Bandwidth: 5 Hz to 35
kHz. S/N Ratio: 110 dB below lull power
output. short clrculted input. Damping
Factor: 170 at 5 ohms. 1 kHz. Input Sensi-
tivity: 1.4 volts. Input Impedance: 75 k
ohms. Dimensions: 15% In. w x 57/- In. h
x 12% in. d. Suggested retail price:
$349.50 (optional walnut case extra).

It's been just about two years since
we reviewed Sony's preamplifier-control
chassis. Model TA-zooo (Auplo. Dec. 68).
At that time we (and Sony) would have
had to recommend a competitor's power
amplifier as the only worthy companion
to this magnificent preamplifier. With the
introduction of the TA-SZOOF Stereo Am-
plifier the people at Sony need no longer
be put in that embarrassing position. for
this new "powerhouse" ls ideally suited
for use with that. or any other high-quality
professional or semi-professional control
chassis. While strictly speaking. the TA-
3200F Is a basic" power amplifier. It
does offer some of the flexibility of an
integrated amplifier. as can be seen by
examining the front panel layout shown
In the photo of Fig. 1. At the lower left of
this solid gold-anodized extruded front
panel Is a lever-type power on/off switch
and an indicator light. A rotary speaker
selector switch follows. with positions
for "main." remote," "both." or no
speaker systems. With no headphone
jack supplied on the TASZOOF. one might
wonder why there is an "off position on
the speaker switch. Sony chose to omit a
headphone jack because the preamplifier
mentioned earlier (TA~2ODO) is equipped
with one and when It Is used it is desir-
able to turn off all speaker systems. This
makes sense in any case. since most
users of basic power amplifiers often
mount this component In outof-the-way
inaccessible places. whereas a preampli-
fier-control chassis. as the name Implies.
is always accessible and is the right
place for a headphone jack in such com-
ponent Installations. Because of the he
mendous power handling capacity of the
TA-SZOOF. Sony wisely incorporated a
power-limiter switch with settings for 100
watts. 50 watts. and 25 watts. This inno-
vation ls intended for speaker protection
and limits the maximum power per chan-

um.
_-u--.

H91

neI to that Indicated by the setting of this
control. A knowledge of maximum power
handling capacity of associated speakers
is necessary in order to take advantage
of this feature. but more and more
speaker manufacturers are now including
this data in their literature since higher-
powered solid-state amplifiers have ap-
peared in recent years.

At the upper right of the control panel
are Individual level controls for left and
right channels. Finally. at the lower right
Is a lever switch which selects one of
two pairs of inputs. We have not seen this
feature on any basic power amplifiers
previously but the more we think about
it. the more sense it makes. For one thing.
some users may want to feed certain
high-level signal sources directly into the
power amplifier. bypassing any preampli-
fier-control chassis altogether. (A tuner
having its own level controls and even
tone controls would be a typical compo-
nent which lends itsell to such connec-
tion). At the same time. other high-level
sources and low-level sources such as
phono. microphone. tape head. etc. must
be fed to a preamplifier before they can
be applied to a basic power amplifier.

As Sony suggests in their well writ-
ten customer's manual. the two input"
feature is also useful for comparing two
signal sources or two preamplifiers.

At the left of the rear panel are the four
inputs iacks associated with the two input
stereo pairs. The "Normal/Test" switch
located directly below the input jacks
activates a low-frequency cut filter. In
the test" position. frequency response
extends down to 5 Hz. as stated in the
specifications. With the switch set to
"Normal." frequencies below 30 Hz are
attenuated at a rate of 6 dB per octave
and this setting is recommended by the
manufacturer for the elimination of IM
distortion that might be caused by sub-

audible rumble frequencies. etc. Two con-
venience a.c. receptacles (one switched.
one unswitched) are provided on the rear
panel. as wall as eight short-proof ter-
minals for the two pairs of speaker sys-
tems with which the amplifier can be
used. The terminals are widely spaced
and are color coded (red for not" leads.
blue for "common or ground leads).
Each terminal has a push button which.
when depressed. exposes a hole lust
large enough to accept a speaker lead.
When released. the speaker lead is locked
In place by spring action. No twisting
of wire under the head of a terminal
screw ls required. nor are any tools
needed for making a safe and permanent
speaker-wire connection.

We thought we had seen some pretty
big power transformers (especially when
one thinks back to high-powered lube-
type amplifiers). but the one used in the
Sony TA-3200F probably beats them all.
as can be seen in Fig. 3. Occupying fully
1/. of the cubic volume of the amplifier. It
is flanked by a pair of BOOO-mlcrofarad
filter capacitors. vertically mounted p.c.
boards, and a massive quartet of heat
sinks-one for each of the four output
transistors. The amplifier. by the way.
weighs Just under 31 pounds out of the
shipping carton.

Circuit Description

To avoid the use of large output
coupling capacitors. the TA-3200F em-
ploys both positive and negative power
supplies. This permits direct coupling be-
tween outpul transistors and loudspeaker.
This approach Improves ultra-low fre-
quency response. provides somewhat
higher power output and ensures full
damping factor and better transient re-
sponse at very low frequencies. The
silicon transistors used in this circuit
(both low-level and output stages) have