m Fully digital signal processing Voicing Equalizer m 40bit floating
point DSP devices m Separate digital filters for Voicing and Equalizer
sections m Wide-format color LCD panel allows direct writing of
response curve with stylus pen m 20 pattern memory m Real-time
spectrum analyzer m Analog connection possible via option boards

Create your ideal listening environment with a stroke of the pen
theDigital Voicing Equalizer makes this dream a reality. Separate sound fieldcompensation (Voicing) and sound field creation (Equalizer) functions
implemented using powerful DSP devices and advanced signal processing
technology. Large, wide-format color display panel allows use of a stylus
pen to directly draw or modify a curve. Connection to analog components
possible using option boards.

What is a "Voicing Equalizer"?
This somewhat unusual term was chosen to symbolize the advanced capabilitiesof the DG-38. While this product is a full-fledged high-precision graphic equalizer in
its own right, it also incorporates a sophisticated system for automatic sound fieldcompensation. It divides the audible frequency range into distinct bands (voices),and lets the user choose a target response curve that is then expressed (voiced)by the unit through a process of precise measurement and adjustment steps. The
result is full control over frequency response characteristics at the listening position.
Through creative use of the capabilities offered by the DG-38, the scope of soundreproduction in the home environment can be significantly enhanced. Get ready toexperience a new dimension of music enjoyment.
When wishing to reproduce high-quality
program sources with optimum fidelity,
the characteristics of the entire
reproduction chain including the speakers
as well as the listening room itself have tobe taken into consideration. The Digital
Voicing Equalizer DG-38 was created withthis fact in mind. It embodies Accuphase's
highly advanced knowledge of digital
signal processing technology for audio
applications. Latest high speed DSP chips
as well as HS-Link input and output
capability make the DG-38 perfectly
suited to handle all high-quality programsources including SACD.
Functionally, the DG-38 is divided into two
equalizing modules. The first is the
VOICING module designed to provide
sound field compensation, and thesecond is the EQUALIZER module thatlets the user creatively and actively shape
the sound field. These central DSP
functions are handled by four 40bit floating
point SHARC processors from Analog

Devices. The
display of the
DG-38 is asupremely
large, wideformat color
LCD that isconfigured as atouch panel. It lets you simply draw adesired frequency curve with the supplied
stylus pen and immediately hear the
results. Control of other functions is alsoeasily accomplished with this panel. A
spectrum analyzer function has been
newly incorporated, providing a visual
representation of the spectral content of
any source in real time.
The DG-38 can be connected to otherdigital Accuphase components such as
the DP-100/DC-101, DC-330, DP-85, andDP-77 via the HS-Link interface. Analog
components can be accommodated byinstalling suitable analog input/output
option boards.

DG-38 Features
n Fully digital Voicing Equalizer with 40bit floating point
DSP devices for digital signal processing.
n 192 kHz/24 bit input/output interfacen Two equalizing modules: sound field compensation(VOICING) and sound field creation (EQUALIZER)n Large, wide-format color LCD panel (154 × 58 mm)
n Touch panel and supplied stylus pen• Allows direct drawing of response curve onscreen• Cursor keypad can be called up for pinpoint
operation and touchup
Call up cursor pad to select frequency and adjust levelby moving cursor right and left or up and down.

• Control functions by tapping or dragging symbols
displayed on screenn 20 memory slots to store entire patterns including
target curve, pre-compensation curve, postcompensation curve, equalizer curve etc. Data sets
can be given a name and called up or modified at
any time.
Call up input panel for character
input or editingn RS-232 connector for interfacing with a computern Sound field measurement microphone AM-28
supplied

Supplied stylus pen can be used to draw any
desired response curve.

n Supplied RemoteCommander RC-30

Fig. 1 DG-38 Block Diagram

Controls input selector,
equalizer on/off, memory
recall, memory number
up/down.

Two main circuit as semblies with four highspeed 40bit floating
point DSP chips, Ultra
Jitter-Free PLL circuit,tone generator, HSLink en-coder/decoder,digitalinput/output
connectors etc.

Sound field compensation (voicing)Sound field creation (Equalizer)
Because the DG-38 incorporates both measurement and adjustment functions,accurate sound field compensation can be carried out easily. 68 IIR typefilters with 1/6 octave spacing are used for measuring the sound field, andthe resulting data provide the basis for accurate compensation.
This screen gives access to various functions including microphone setup,target curve setup, auto compensation, display of frequency response
before and after compensation, and calling up or saving frequency response
curves.
When power to the DG-38 is turned on, the Equalizer screen shown here appears.
In this mode, the user can create a desired sound field by drawing a frequency
response curve. This can be done with the supplied stylus pen directly on thedisplay screen. A cursor keypad is also available, for manually creating the curveor making adjustments. The values set using this screen are automatically readand applied by the digital filters.

The DG-38 has four main
operation modes:"Voicing", "Equalizer","Analyzer", and"Configuration".
Four buttons on the front
panel are used to selectthe respective mode.

The equalizer filter section uses 74 IIR + FIR hybrid type filters with 1/6 octave
spacing. Because the digital filters for sound field compensation and sound fieldcreation are separate, equalization can be further modified after the sound fieldcompensation (voicing) curve has been established.
CONFIGURATION

Spectrum analyzer

The spectral content of the input signal can be displayed on a spectrum
analyzer screen with 1/3 octave spacing, 35 bands, and real-time operation.
This function is entirely separate from the adjustment functions of the unit,
allowing you to monitor peak levels in real time. Comparison of Voicing andEqualizer on/off condition and checking of right/left frequency distribution
are also possible.

Configuration

This screen lets you make environment and function settings, such as
selecting the Voicing/Equalizer modes, controlling levels, left/right balance,screen brightness and contrast, screen data send etc.
Functions are activated directly on the screen with the stylus pen.

Advanced compensation functions

VOICING application examples

The DG-38 automatically measures the sound field and provides accurate compensation based on target characteristics representing
the ideal sound field. Compensation may be performed using ) a preprogrammed standard reference curve, * an automaticallycreated target curve, or +a freely created curve.
A dedicated sound field measurement microphone with
controlled frequency response is supplied with the
DG-38.
The microphone is a 1/4-inch
type back-electret condenser
type with ultra-thin diaphragm, which assures linear
response over a wide frequency range.

For testing, the DG-38 outputs four warble tones of different frequencies
simultaneously. These are heard as a combined sound.

Speaker

Microphone

Setup screen for Voicing level
and channel, microphone settings, etc.
Preamplifier

Power amplifier

The internal test signal generator of the DG-38 produces warble tones which are used to drive the speakers via the power
amplifier. The sound travels through the sound field and is picked up by the microphone for sound field measurement.

Ex. 1 Using preprogrammed standard reference
curve

Ex. 2 Compensation with automatically created target
curve

Ex. 3 Compensation with freely created curve(Creating a curve that incorporates speaker and roomcharacteristics)

Using the stylus pen, any desired target curve can becreated freely.
First, automatic measurement of characteristics before
compensation is carried out.
m Speaker and room characteristics (Separate measurementfor L, R or simultaneous L/R measurement is possible)m Individual speaker characteristics

Flat

+

The DG-38 comes with four preprogrammed reference curves:
three curves with high-end rolloff (–1 dB, –2 dB, –3 dB per
octave) and flat response.

Auto generation of
curve for flat response

If flat response was selected forcompensation

Auto compensation is performed based on the target
curve. By comparing the characteristics before and after
compensation, the difference can be easily checkedvisually as well as aurally.
Based on the measured characteristics before
compensation, a target curve for achieving balanced L/R
response at the listening point is created automatically.
The curve can be further modified on screen to reduce small
peaks and dips.

L/R channael characteristics example for performing soundfield compensation with the "flat" target curve. Peaks anddips caused by listening room acoustics and speakercharacteristics are evened out, resulting in approximately
flat response.

Auto compensation is performed based on the createdtarget curve. By harnessing room characteristics andspeaker characteristics, it is possible to counter theeffect of standing waves and achieve well balanced
compensation for the right and left channels.

Ultra Jitter-Free PLL circuit~Accuphase original digital interface~

The operation of a D/A converter must be synchronized with the input signal.
For this purpose, a phase-locked loop (PLL) circuit generates a master clock
which is used as system reference. In the DG-38, the so-called Ultra JitterFree PLL circuit developed by Accuphase is used.
As shown in the illustration, this circuit consists of a detector for the preamble
component (a kind of start marker for the L/R signal) and a voltage-controlled
oscillator (VCO) using a quartz crystal element. The master clock producedby this PLL circuit is totally free from the effects of pulse distortion and jitter.

HS-Link is an ultra high-quality digital audio interface developed by Accuphase. It supports
send/receive verification for copyright protection. The LVDS (Low Voltage Differential
Signaling) principle allows a single dedicated HS-Link cable to transmit signals using
advanced formats such as 2.8224 MHz/1 bit or 192 kHz/24 bit. Conventional digitalformats are also supported. Because digital audio data are transmitted with utmost
fidelity, the sound quality achieved by HS-Link is simply outstanding.

DAI signal input

Preamble
detector

Phase
comparator

HS-Link: High Speed Link

Preamble signal(pulse distortion removed)LoopfilterDivider

Principle ofUltra Jitter-Free PLL circuit

Master clock output

HS-Link Block Diagram

Connections between DG-38 and other components
The DG-38 is a Voicing Equalizer with many functions. By incorporating it into an existing audio system,
the entire reproduction chain including the speakers and the listening room can be measured andoptimized to achieve the best possible playback quality.
The DG-38 can be connected to digital components such as the DC-330, DP-85, or DP-77 (with DO2-HS1
installed) via HS-Link. This provides full support for digital signals using various sampling frequencies,
including the DSD signal of SACD sources and 192 kHz/24 bit signals. To connect analog components,
separately available option boards can be installed which incorporate high-quality A ó D converters thatkeep signal degradation to an absolute minimum.
n HS-Link, optical, and coaxial digital input/output connectors provided as standard equipmentn Input signal selector menu of DG-38 allows the user to choose HS-Link, optical, coaxial, or installed
option board
n Connection to analog components implemented via option boardsn Up to four option boards can be installed

Option boards that can be used in the DG-38
KAnalog boards

KDigital boards* The analog input signal is converted to a digital signal by an on-board A/D converter. The
digital output signal is converted to an analog signal by an on-board D/A converter.

Line Input Board
AI2-U1

Digital Line Input/Output Board
DIO-OC1[Number of slots used: 1]

Balanced Input Board
AI2-B1[Number of slots used: 1]

Provides coaxial and optical
inputs and outputs.

[Number of slots used: 2]* Conventional high-level input* Input signal is converted to 24-bit digital signal by on-board
A/D converter.

* Supports sources with sampling
frequencies up to 96 kHz.

* Internal sampling frequency selector should be set to 96 kHz.
KFor balanced connections

KFor unbalanced connections

Balanced Output Board
AO2-B1

Line Output Board
AO2-U1HS-Link cable
HDL-15[Number of slots used: 2][Number of slots used: 2]Serves for transmission ofdigital signal corresponding to
the HS-Link interface.

* Conventional high-level output* On-board high-precision D/A converter supplies analog output
signal.

* Shielded twisted pair 8-conductor
OFC cable (TIA/EIA568-A CAT.5)* D/A converter type: 192 kHz (max.), 24 bit, MDS Plus.

* 3 m, 5 m, 7.5 m, and 10 m cable
lengths are also available.

KFor unbalanced connections

Sound field compensation for all program sources input to DC-330
Analogcomponentsuch as tuner
or CD player

DP-100 or DP-85
transport output,
DP-77 with
DO2-HS1 installed

Audio cable

HS-Link cable

KFor balanced connections

Connection example for use of DC-101 or other DAC
DP-100 or
DP-85transport
output, DP-77
with DO2-HS1
installed

HS-Link cable(supplied with DP-100)

HS-Link cable

HS-Link cableor DP-85/DP-75V* Set EXT DSP
button on DC-330
to ON forconnection to
DG-38
DI2-HS1
installed in
EXT DSP slot

Analog output
Audio cable

Optical fiber cable

DO2-HS1
installed (1 slot)
Optical fiber cable

Optical fiber cable
75-ohm coaxial
cable[Power amplifier

75-ohm coaxial cable

Preamplifier

DIO-OC1 installed
DI2-HS1
standard equipment in EXT DSP slot
(1 slot)
in DC-101(2 slots)[

DI2-HS1
installed(2 slots)

75-ohm coaxial cable* EXT DSP of DC-101 OFF:Sound field compensation for DP-100 connected with HS-Link* EXT DSP of DC-101 ON:
Sound field compensation for source connected with coaxial cable or
optical fiber

Digital component
such as CD transport
Digital component suchas CD transport, DAT or MD recorder
Right speaker

Left speaker

Connection of analog output and digital output to DG-38
SACD transport

Connections to analog components
Example 1:
Example 2:

DG-38 connected to REC/PLAY jacks of RECORDER loop
DG-38 connected between preamplifier and power amplifier (see below)

CD player, tuner, etc. Û Example for connecting the output of adigital component such as a SACD/CDtransport and the analog output of acomponent such as a CD player directly to
the DG-38compensation for source
connected with coaxial cable or optical fiber
Optical fiber cable
Audio cable

CD transport, MD, etc.

75-ohm coaxial cable

HS-Link cable
Audio cable

Preamplifier

Audio cable

Input board
For balanced connection:
AI2-B1 (2 slots)
For unbalanced connection: AI2-U1 (1 slot)

Audio cable

Preamplifier

Power amplifier

Output board
For balanced connection:
AO2-B1 (2 slots)
For unbalanced connection: AO2-U1 (2 slots)

Input board
For balanced connection:
AI2-B1 (2 slots)
For unbalanced connection: AI2-U1 (1 slot)

Output board
For balanced connection:
AO2-B1 (2 slots)
For unbalanced connection: AO2-U1 (2 slots)

Connection example for multi-amped system with DG-38

Multi-amped system with DG-38 between DC-330 and DF-35

DF-35

Direct HS-Link connection of DG-38 ð DC-330 ð DF-35 creates
multi-amped system with support for SACD sources.
Multi-amped system to handle all sources input to DC-330

Û When connection to DG-38 is madevia coaxial or optical fiber cable,
sources input to DC-330 withsampling frequencies up to 96 kHz
are supported.
75-ohm coaxial cableÛ HS-Link connection handles all sources that are input
to the DC-330, including SACD.

Optical fiber cable

HS-Link cable

DIO-OC1 installed in
EXT DSP and OUTPUTS slots

HS-Link cableMulti-amped system with analog preamplifier and DG-38/DF-35
Û Output of analog preamplifier is connected to DG-38 for sound field compensation,and digital output of DG-38 is sent to DF-35.

DO2-HS1
installed

DO2-HS1
installed in
OUTPUTS slot
DI2-HS1 installed in
EXT DSP slot (2 slots)* Set EXT DSP button of DC-330 to ON for sound fieldcompensation of input sources.
* OUTPUTS slot of DC-330  DF-35 input* All connections made with HS-Link cable

Audio cable

Analog output

75-ohm coaxial cable

DI2-HS1(2 slots)

Left speaker

Low range
power amplifier

Optical fiber cable

For balanced connection:
AI2-B1 (2 slots)
For unbalanced connection: AI2-U1 (1 slot)

Analog preamplifier

Set switch on board
to 96 kHzHigh range Right speaker
power amplifier

Audio cable

Audio cable

Power amplifier

Audio cable

Power amplifier
DIO-OC1 (1 slot)

n Front panel

DG-38 Guaranteed Specifications[Guaranteed specifications and standard compliance are measured according to EIAJ CPR-2101.]m Voicing

1/6 octave 68-band IIR filter
Adjustment range ±12 dB

m Equalizer

1/6 octave 74-band hybrid IIR filter + FIR filter
Adjustment range ±12 dB

m Measurement signal

Warble tones

m Frequency Response
Curve Input Principle

Direct drawing with stylus pen or input with cursor keypadm Spectrum Analyzer

1/3 octave, 35-band real-time type
Display level: +20 dBFs to –100 dBFs (4 ranges, switchable)m Reproduction Frequency
Response

0.5 - 50.000 Hz +0 –3.0 dB(For sampling frequency 2.8224 MHz or 192 kHz)
4.0 - 20,000 Hz +0 –0.3 dB

House the supplied stylus pen heren Rear panel
Option board
expansion slots

0
A Display
B Voicing button
C Equalizer button
D Microphone input jack
E Power switch
F Analyzer button
G Configuration button

H Digital inputs
HS-Link
COAXIAL OPTICALI Digital outputs
HS-Link
COAXIAL OPTICALJ RS-232 interface
K AC power connector0

Remarks
0 This product is available in versions for 120/230 V AC. Make sure that the voltage shownon the rear panel matches the AC line voltage in your area.
0 The shape of the AC inlet and plug of the supplied power cord depends on the voltage rating
and destination country.
0 Microsoft ® and Windows ® are registered trademarks of Microsoft Corporation in the
U.S. and in other countries.

m Gain+6 to –90 dB, variablem Digital Inputs

HS-Link Connector type: RJ-45 (dedicated HS-Link cable)
OPTICAL Format:
EIAJ CP-1201/AES3 compliant
COAXIAL Format:
EIAJ CP-1201 compliant
32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz
Sampling frequency:(16 to 24 bit 2-channel PCM)
[With HS-Link only]
176.4 kHz, 192 kHz (16 - 24 bit 2-channel PCM)
2.8224 MHz (1 bit 2-channel DSP)

m Digital Outputs

HS-Link Connector type: RJ-45 (dedicated HS-Link cable)
OPTICAL Format:
EIAJ CP-1201/AES3 compliant
COAXIAL Format:
EIAJ CP-1201 compliantm OS

Microsoft® Windows® CE operating system

m Power Requirements

AC 120 V / 230 V, 50 / 60 Hz(Voltage as indicated on rear panel)m Power Consumption

23 watts

m Maximum Dimensions

Width: 475 mm
Height: 150 mm
Depth: 395 mm

m Weight

12.3 kg (27.1 lbs) net
17.3 kg (38.1 lbs) in shipping carton

Supplied
Accessories

m Stylus pen
m Microphone cablem Coaxial digital cable (2)m Remote Commander RC-30(18-7/10")(5-7/8")(15-9/16")

m Microphone AM-28
m Microphone holderm HS-Link connector housing (2)m AC power cord

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

http://www.accuphase.com/

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