Accuphase PS-500-V Brochure

m AC voltage stabilizer based on w aveform shaping technology m Superior

waveform compensating power m Excellent current capability m Highly
effective interference rejection m Built-in meter allows monitoring of output
power, input/output voltage, and input/output distortion m Elaborate
protection features m Large "Super Ring" toroidal transformer

Tap into a totally clean source of AC energy, free from distortion and high­frequency noise. Revolutionary wa veform shaping technology enables highly
precise compensation, providing a pure energy source with 120 V AC ± 2%
(or 230 V A C ± 2%). Audio or video equipment with a total power consumption
of up to 510 VA can be connected, for a drastic improvement in sound and
picture quality . Monitoring of output power , input/output volta ge, and input/
output distortion is possible.

The PS-500V is a revolutionary product which
removes the noise components from the AC power
line and improves signal quality by continually
monitoring and shaping the power supply waveform.
As a result, sound and picture quality of audio and
video equipment is drastically improved.
The AC power lines in ordinary homes as well as in
office buildings or recording studios invariably suffer
from high amounts of noise and waveform distortion.
The ideal wavef orm of the power supply is sinusoidal,
but when various electrical devices are connected to
the same power source, unwanted v oltage fluctuations
will occur. In addition, appliances containing digital
circuits, such as computers or telephones, emit high­frequency noise components that can enter audio or
video components via the power supply and severely
affect sound or picture quality by causing
intermodulation noise and distortion. Only when such
noise interference is removed and totally clean power
is supplied are audio and video components able to
develop their full potential. This is especially true for
high-end equipment. Consequently, upgrading the
quality of the AC power source is bound to result in a
drastic improvement in the ov erall performance of your
audio/video system.
The PS-500V constantly monitors the input voltage
waveform and adds or subtracts e xactly the required
amount of compensation to achieve a perfectly
regular, sinusoidal waveform. The compensation
required by this innovativ e technique typically is only
a fraction of overall power. The PS-500V therefore
operates with high efficiency and produces little heat,
allowing it to be designed as a fairly compact and
lightweight unit. Because the output impedance of its
AC outlets is extremely low, any combination of
components with a total power consumption of 510
V A maximum can be connected. Since it contains no
oscillators or switching circuitry, the PS-500V itself
does not act as a source of spurious high-frequency
noise.

AC V oltage Stabilizer Based on Wa veform Shaping
Technology

The PS-500V accepts AC power on the input side,

Power suppl y wa vef orm and PS-500V output waveform

Almost every electrical device used in an household converts the
AC supplied by the outlet into DC current for powering its internal
circuits. This task is perf ormed by a rectifier. As shown in photog raph

, the rectifier load current has a pulse waveform with a large

current flowing momentarily in the vicinity of the voltage peak.
This causes a voltage drop, resulting in clipping of the voltage

waveform, as shown in photograph . A clipped waveform with a
high amount of distortion contains many unwanted frequency
components, or harmonics. When entering the audio circuitry of
an amplifier through the power supply , such harmonic components
can interfere with the audio signal and cause intermodulation
distortion, which has a highly detrimental effect on sound quality.

When passing through the PS-500V, the deformed waveform
is restored to its original sine wave pattern, as shown in
photograph .

Frequency spectrum of power line
(photo )

Frequency spectrum of power line

processes it using internal control circuitry, and
supplies it as clean AC power on the output side. Most
of the AC energy from the input is carried over to the
output. The loss introduced by the PS-500V is very
small, since it consists only of the power required for
waveform compensation. Compared to conventional
AC voltage stabilizers, efficiency is much higher and
excess thermal energy is low, allowing the unit to be
made relatively small and lightweight. Since the power
supply frequency is synchronized to the input, an
internal oscillator is not required. Therefore the unit

Frequency spectrum of PS-500V
output (photo )

Photo Current waveform of rectified
load

Photo Voltage wav eform of AC line

(distortion approx. 3%)

Photo PS-500V output wa veform

(distortion approx. 0.2%)

itself does not
generate any
high-frequency
noise.
Figure 1 shows a
block diagram of
the unit. The
signal from the
secondary
winding S
transformer
reaches the
adding/sub­tracting circuit
and appears at
the output as
output voltage
(e
output voltage is
routed to the –
input of the
waveform
comparator for
waveform
comparison. The
S2 signal from
the transformer goes to the reference waveform
generating circuit where it becomes the high-precision
sine wavef orm (e
of 50/60 Hz. This sine wave signal is then routed to
the + input of the waveform comparator to be used
as the reference signal. By comparing the two input
signals, a differential component is extracted. Based
on this information, the adding/subtracting circuit can
provide exactly the required amount of compensation
for turning the output into a high-precision sine
waveform.

1 of the

0). A part of the

i) synchronized to the input frequency

Superior Waveform Compensating Power

When the input voltage is 110 V (220 V), the voltage
at the secondary side of the transformer will also be
110 V (220 V). To b ring this to 120 V (230 V), 10 v olts
must be added, as shown in Figure 3 (a). Conv ersely ,

if the input is 130 V (240 V), 10 volts must be
subtracted to yield 120 V (230 V), as shown in Figure
3 (b). In actual operation, the peak value of 10 V,
namely 14.1 V is added or subtracted.
Comparing a precise sine wave synchronized to the
input frequency with the output voltage yields a
compensation waveform which is imposed on the
output voltage. Consequently, for an input voltage
range of 108-132 V AC (200-253 V A C) and a constant
load of 510 W, the output voltage is kept constant at
120 V ±2% (230 V ±2%), with a maximum distortion
ratio of 0.3%. These values demonstrate the
outstanding waveform compensation ability of the
PS-500V.
Note: The above explanation is for the 120 V AC
version of the PS-500V. Figures in brackets refer to
the 230 V AC v ersion.

removing any high-frequency noise components
present in the power line, such as generated by digital
equipment. The primary and secondary windings of
the power transformer are kept totally separate, and
the fully shielded design shuts out any externally
induced noise.
Since the PS-500V uses the AC feedback principle,
output impedance is extremely low . This pre vents an y
possibility of mutual interference between components
connected to the outputs of the PS-500V.

Built-in Meter Allows Monitoring of Output Power,
Input/Output Voltage, Input/Output Distortion.
Overload Is Indicated by Flashing Meter Illumination.

The meter of the PS-500V lets the user see at a glance
how much power (VA) the connected equipment is
consuming at any given time. This is especially helpful
for components such as integrated amplifiers or po wer
amplifiers whose power consumption differs
considerably depending on the volume setting and
actual music signal. The maximum output power rating
of the unit is 510 V A. When this is e xceeded, the meter
illumination flashes as a warning indication.

Excellent Current Capability

The power amplifier which performs waveform
compensation is configured as a pure complementary
symmetrical circuit using current feedback for

unsurpassed
operation stability.
The output stage
uses transistors
rated for a
maximum current
of 10 amperes.
These devices are
connected in a
10-parallel
complementary
push-pull arrange-

Assembly with input voltage/

distortion monitoring circuitry

ment, which boasts excellent current capability.

Elaborate Protection Features Assure Total
Operation Safety

When a problem occurs during operation, the circuit
breaker integrated in
the power switch
immediately shuts
off the power, to
protect the unit and
any connected
components.

Assembly with protection
circuitry

n Assembly with output stage with 10-

parallel push-pull multi-emitter devices
mounted to large heat sink, waveform
compensation amplifier for addition/
subtraction, comparator for reference

waveform and output waveform,

deviation detector, etc.

Highly Effective Interference Rejection

The input side of the PS-500V is
equipped with a line
filter for

= If an input current overload occurs, such as when

the output is short-circuited, the power is shut off.

> In case of momentary power overload, such as

caused by inrush current when a component is
switched on or when a power amplifier reproduces
a peak passage in the music, a current limiter
goes into action. For the 120 V version, the
maximum current is 60 A and for the 230 V version
it is 30 A.

? When DC voltage is detected in the output or when

the output voltage exceeds the maximum rating,
the output is switched off to protect connected
components.

@ When the temperature of the internal heat sink or

power transformer exceeds 110ºC, the circuitry
is automatically switched off.

Strong Power Supply With Large "Super Ring"
Tor oidal Transformer and High Filtering Capacity

The power transformer plays a vital role in any pow er
supply . The PS-500V uses a large toroidal type rated

Coil

Conventional toroidal
transformer

Fig. 4 Cross section of toroidal transformer core

Core

"Super Ring" type toroidal
transformer of PS-500V

Coil

for 750 VA. Toroidal power transformers have large­gauge copper wiring on a donut-shaped core, resulting
in very low impedance, high efficiency, and compact
dimensions.

Multiple Output Connectors

The PS-500V can supply a number of components
such as a CD player, DAT recorder , preamplifier , power
amplifier or other audio or video components, provided
the combined power consumption is less than 510
VA.

Power Meter Indication and Load

The power consumption of electrical equipment, as indicated on the equipment itself
and in catalogs and other documentation, is usually given in watts (W). This figure
represents the so-called effective po wer which is stated according to legal requirements.
However, the actual power drawn by the equipment is larger than the effective power .
This is called the apparent power which is calculated b y multiplying the applied voltage
with the actual current. The unit for apparent power is V A (v olt-ampere).
Since the value shown by the power meter of the PS-500V in the "VOLT-AMPERE"
position is the apparent power, the reading will be higher than the po wer consumption
(W) given in catalogs and specification sheets.

m The rated power limit of the PS-500V is 510 VA. When

deciding on equipment to be connected, power
consumption figures given in catalogs and the like can be
used for a general estimate, but actual po wer consumption
should be checked using the meter.

m The power consumption of integrated amplifiers and power

amplifiers varies considerably depending on the actual
audio output. After connecting such equipment, perform
playback and verify that power consumption does not
exceed 510 V A when peaks in the m usic are reproduced at
high volume lev els.

m In case of overload, the meter illumination flashes. Reduce

the load by reducing the number of connected components
until the illumination stops flashing and stays constantly lit.

m For reference, some Accuphase products are listed shown

below.

n FRONT PANEL

Meter of 120 V
AC version

Can be connected:

Preamplifiers, CD players, tuners
and other low-power components
E-407, E-306V, E-211, A-20V

Can be connected at normal
volume settings (*):

P-1000, P-700, P-550, P-450

Cannot be connected

A-50, A-50V

(*) When driving loudspeakers with an

impedance of about 8 ohms to normal
listening levels

(The photograph shows the 230 V AC version.)

PS-500V Guaranteed Specifications

120 V version 230 V version

Rated output capacity 510 VA (continuous)
Rated output voltage 120 V AC ±2.4 V 230 V AC ±4.6 V
Rated output current 4.2 A 2.2 A
Output frequency 50 Hz or 60 Hz (identical to input frequency)
Instantaneous peak current capacity 60 A 30 A
Output waveform THD 0.3% or less
Rated input voltage 120 V AC 230 V AC
Input frequency 50 Hz or 60 Hz
No-load power consumption 55 W
Cooling principle Natural air cooling
Meter

.........................................................................................................................................................................

VOLT-AMPERE

.........................................................................................................................................................................

VOLTAGE INPUT/OUTPUT

(green zone of scale)

.........................................................................................................................................................................

DISTORTION INPUT/OUTPUT 0 – 6%

Dimensions 475 mm (18-11/16”) width,

Weight 23.8 kg (52.5 lbs.) net

The meter illumination flashes when an overload occurs

120 V AC ±5% 230 V AC ±5%

0 – 510 VA

180 mm (7-1/16”) height,
394 mm (15-1/2”) depth

27.0 kg (59.5 lbs.) in shipping carton

n REAR PANEL

Output connectors of
120 V AC version

The usable power supply
voltages are indicated.

) +

) Power switch/circuit protector
* Meter (Output power, input/output voltage, input/output distortion)
+ Meter operation selector

VOL T-AMPERE VOL T AGE INPUT/OUTPUT DISTORTION INPUT/OUTPUT

The PS-500V is available in a 120 V AC and 230 V AC version. The actual allowable voltage is indicated besides the AC power

✻

connectors on the rear panel. Be sure to check this indication before using the PS-500V.

✻

R

Caution

❇ Specifications and design subject to change without notice for improvements.

This product can be used only on a regular household AC circuit rated for 120 V or 230 V AC. Using the product with portable AC
generators, airplane or ship power generators or other types of power sources is not possible.

✻

This product is designed to improve the quality of AC power supplied to audio or video components. Do not use it to power industrial
type equipment or common household electrical appliances.

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http://www.accuphase.com/

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,

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, Output connectors (AC outlets)

- Power connector (for supplied power cord)

Remark

0 The 120 V AC and 230 V AC versions of the PS-500V differ regarding meter voltage indication,

AC output connector shape, supplied power cord, etc. Mak e sure that you have the correct v ersion.

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PRINTED IN JAPAN D0010 851-0166-00 (AD1)

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