CLEAN POWER SUPPLY

PS-550Accuphase Laboratory, Inc.

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Accuphase Clean Power Supply series is an epochmaking audio product that enables all users to improvetheir power supply quality by forming an ideal power
supply waveform with precise analog signal processing.
It shows a terrific performance to obtain great sound andimage quality.
After launching PS-500 in 1996, Accuphase has been
making improvements one after another, as known as
PS-500V, PS-510, PS-520, and PS-530.
Accuphase makes PS-550 known to the public, the 6thgeneration Clean Power Supply succeeding PS-530.
The main features of PS-550 are…
- Multiple functions liquid crystal display- Precise reference signal generator- Low Total Harmonic Distortion- Low power consumption1Differences in front view
PS-530Multiple functions
liquid crystal display

PS-550Accuphase Laboratory, Inc.

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PS-550 newly adopts the multiple functions liquid crystal
display.

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Display mode
• Seven modes can be selected

Input waveform

Output waveform

Display OFF switch

PowerVoltage

Distortion

Accuphase Laboratory, Inc.

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The PS-550 has seven display modes.
- Output power- Input(AC line) voltage- Output voltage- Input Total Harmonic Distortion- Output Total Harmonic Distortion- Input waveform- Output waveform
The multiple functions display can be turned off.

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Internal View
Reference signal generator

Isometric output wiring

22000μF capacitor x 2

High-efficiency large
toroidal transformer
with electrostaticshield

Power switch withcircuit breaker

Power amplifier block

Accuphase Laboratory, Inc.

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The massive power supply section sits at the unit's
center, and power amplifier blocks are on the right side.
The power transformer has an electrostatic shieldbetween the primary and secondary windings to prevent
coupling.
All the internal output wires are isometric and set at thesame length. It helps the electric performance and soundquality of each AC outlet keep the same level.
The power switch has a circuit breaker function that
operates on overcurrent.

4Power amplifier block• 10-paralleled push-pull bipolar transistors output stage

Power amplifier block

Accuphase Laboratory, Inc.

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The power amplifier block that performs
addition/subtraction for waveform compensation uses thepure complementary 10-paralleled push-pull bipolartransistors output stage.
It leads to the success of high peak output current andlow output impedance.

5Reference signal generator• Guaranteed Total Harmonic Distortion: ≦0.08%

BPF
AC LineBEF x 6BPF
ReferenceSignal

Limiter

Block diagram of reference signal generator

BPF: Band Pass Filter
BEF: Band Eliminate Filter

Accuphase Laboratory, Inc.

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The Reference Signal Generator is the circuit thateliminates the noise and distortion components in AC line
signals with filters and generates the reference signals forwaveform shaping.
PS-550 has evolved this Reference Signal Generator
much more precisely.
PS-550's configuration is that two stages of the Bandpass
Filters remove undesired out-of-band signals. Then, thesix stages of the Band Eliminate Filters also remove theharmonic component.
These two features contribute to the low distortion andlow noise characteristics of the reference signals.

6Clean out the power supply waveforms• Significantly reduces harmonic distortion and noise
3rd harmonic distortion of 50Hz
3rd harmonic distortion of 50Hz
40dB

Power line

PS-550 output

Example of the frequency spectrum at 50Hz power lineAccuphase Laboratory, Inc.

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Accuphase's original waveform correction technology provides
outputs with significantly reduced harmonic distortion andnoise. Third-order harmonics are suppressed by more than 40dB.

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