DIGITAL FREQUENCY DIVIDING NETWORK● High-speed, high-precision DSP realizes fully digital signal processing in channel divider units● Standard configuration allows 4-channel (4-way) system setup ● Impressive 3101 point cutoff
frequency points ● Steep 96 dB/oct attenuation slope ● Delay function to adjust delay time
settings between different speaker units ● Delay compensator automatically corrects delays infilter signals ● A/D converter driving 4 parallel circuits using ANCC ● MDS+ D/A converter driving
4 parallel circuits using ANCC ● Selectable monophonic output mode for enhanced specifications

Multi-channel divider that achieves full digital signal processing
The DF-75 Digital Frequency Dividing Network can support 4-way system setups. The high-speed
64-bit floating point DSP allows for optimal filtering. Cutoff frequency points have been expanded
dramatically from 59 to 3101, accommodating a variety of performance demands. The network
also achieves a steep 96 dB/octave attenuation slope. Beyond that, the time delay function allows
for time alignment in 0.5-cm steps while a delay compensator automatically corrects signal delaysin the filter circuits. Each divider unit can also be configured in a monophonic setting.

Innovative Technology■High-speed, high-precision DSP implements fully digital

signal processing

This digital channel dividing network is designed to serve as the corecomponent in a multi-amped system. The digital filter uses a 64-bit
floating-point DSP capable of high-speed calculations thanks to a52-bit mantissa and 12-bit exponent section. With its highly precise
calculations, the floating-point DSP dramatically improves thedynamic range, allowing very steep cutoff slope settings of 48 dB or
96 dB per octave. Phase switching, delay, and level control are all
performed in the digital domain ensuring high dimensionality of thesource characteristics. The result is ultra-precise filtering performance
free from adverse effects caused by temperature changes or aging.

■ 3101 selectable filter cutoff frequency points
The conventional 59 cutoff frequency points have been greatly
expanded to 3101 points, allowing for radically more choices whenselecting cutoff frequencies.
Cutoff frequencies (Hz)Frequency steps (Hz)
Rotation of VALUE knob
without pressing itRotation and pressingof VALUE knob

10.0,10.1, …,99.9

0.110100,101, …,

999

11001000, 1010, …,

9990

10100010.0k, 10.1k, …, 50.0k

0.1k3k■ Six filter slope characteristics with up to 96 dB attenuation

per octave

〔dBr〕
PASSc
B/o

6d

B/

1212−40

18/odB

ct

ct

B/o

96dB/o

48dct

/oct

−80t/o

96dB

−70ct

dB
24−60

oc

dB

ct

−30

−506dtoc/dB/o−20t

ctt/oocdB dB/24ct
B/o48dHigh-speed, high-precision DSPPASS0−1018The DF-75 has six filter
slope characteristics (6dB,12 dB, 18 dB, 24 dB,
48 dB, and 96 dB peroctave). The 96 dB/octave
setting in particularminimizes sound interruption in adjacent bands,
allowing for the creationof a multi-amped systemthat analog channel
dividers cannot achieve.

−90−100
1020 3050 70 100

200500Frequency

1k2k 3k

5k 7k 10k〔Hz〕

Divider unit slope characteristics (bandpass filter)(Cutoff frequency setting 100 Hz for lower and 1 kHz for upper range)

Impeccable Sound Quality■MDS+ (Multiple Delta Sigma) converter with four parallel circuits

The MDS+ conversion principle drives ⊿Σ (Delta Sigma) type D/Aconverters in parallel to achieve a D/A converter with drastically improved
performance. In the DF-75, four Hyperstream™ DAC chips (ES9028PRO
made by ESS Technology) are driven in parallel to improve the theoretical
performance specifications like distortion, noise characteristics, andlinearity by a factor of 2 (= √4). Additionally, the I-V converter circuits rely on
Accuphase’s original low-noise, low-distortion ANCC* circuits. Performance
improvements from the MDS+ conversion principle operate independentlyof signal frequency and level, allowing for reduction of ultra-low level noisethat conventional Delta Sigma D/A converters struggle to remove.
(Normal phaseoutput)

The A/D converter incorporates the AK5578EN circuit from Asahi
Kasei Microdevices. Combining this A/D converter with ANCC to drive
four parallel circuits allows for low noise and ultra-low distortion.
Filter amplifier assembly

DAC assembly

I (current) -V (voltage) converter

DAC 1I-V(Reverse phaseoutput)

DACoutput

DAC 2Digitalinput■32-bit A/D converter driving 4 parallel circuits+LevelShifter

−

DAC 3

Subtraction

DAC 4
Driving four parallelcircuits

I-V

Currentsumming
I-V: I-V conversion amplifier with ANCC

4MDS+ conversion principle D/A converterTransformer*: ANCC is a unique Accuphase technology that improves performance by using a secondary amplifier to cancel out noise and distortion from the main amplifier.

Divider units

Center unit

① Low-range cutoff frequency② High-range cutoff frequency

PASS, 10 to 50,000 Hz

10 to 50,000 Hz, PASS

③ Low/range slope
6, 12, 18, 24, 48, 96 dB/oct⑤ Output level– 40.0 dB to +12.0 dB⑦ Delay compensator
ON/OFF(See next page)④ High-range slope
6, 12, 18, 24, 48, 96 dB/oct⑥ Delay time (convertedinto distance)–3,000cmpage)
to +3,000 cm(See next

ON/OFF⑪ Unit display selector⑧ Phase selector (L/R)
REV/REV
REV/NOR⑩ Output mode selector

Parameter display

STEREOMONO L＋R
MONO LMONO R

Function selector(functions ① to ⑪)

Parameter selector
for each function

Register characters /Input characters

Aluminum top plate with hairline finish

Input can be set
to BALANCED,LINE, HS-LINK,COAXIAL, orOPTICAL.

(See next page)

NOR/NORNOR/REV⑨ Output

Input
display

Side panels with natural wood grain finish

Memorynumberdisplay
Stores up to fivesettings for thedividing network.

Input
selector
Memorynumberselector

High carbon cast iron insulator feetDelay correction diagram

Monophonic mode

Time difference: t 1 Time difference: t 1

Time difference: 0
Delayt1Input❶2-Way system
Use two units for MONO L and two units for MONO R.

Input

Before correction (time difference: t1)

Setting the divider unit to monophonic mode will
improve performance by having the D/A converter
drive the channels in parallel.

Low sounds

High sounds

Low sounds

High sounds

MONO LMONO LMONO R

MONO R

After correction (time difference: 0)

The delay correction from the delay manually corrects the time delay caused by the installation location of the speaker units.

Delay compensator diagram
Time difference: t 2

Time difference: 0

Left channel

Low-range
outputDelaycompensator

Low-pass filter
Input

High-pass filter

After correction(time difference: 0)

Before correction(time difference: t 2)

ChannelB

Power switch

Set the unit using the subwoofer to MONO L+R.
Low sounds

High sounds

MONO L+R

STEREO

Set to OFF

Set to OFF

For subwoofer For high sounds

Front Panel
ChannelA❷Subwoofer (3D) system

High-range
output

The delay compensator automatically corrects any time delays in the filtered signals.

Divider units*1

Right channel

Rear Panel

ChannelCDigital output
HS-LINK

ChannelD

Center unit *1

Display OFF*1: See the previous page for explanations of the features of the display units and center unit.

ChannelDChannelCChannel
B

Analog inputs

ChannelAAnalog outputs
LINE/BALANCED

AC power supply
connector

LINE/BALANCED
Digital inputs
HS-LINK/COAXIAL/OPTICAL

Guaranteed Specifications
FormatCompatible cable
Ver.1
Samplingfrequencies
Ver.2
FormatCOAXIAL
Compatible cable
Sampling frequencies
FormatOPTICAL
Compatible cable
Sampling frequencies
Maximum input level
BALANCED/LINE
Input impedance
BALANCED/LINE
Principle
A/D converter
Sampling frequencies

Accuphase original standard
HS-LINK dedicated cable
32 kHz to 192 kHz (16 to 24 bits, PCM)
32 kHz to 384 kHz (16 to 32 bits, PCM)
IEC 60958/AES3 compliant
75-ohm coaxial digital cable
32 kHz to 192 kHz (16 to 24 bits, PCM)JEITA CP-1212 compliant-(,7$VWDQGDUG¿EHURSWLFFDEOH
32 kHz to 96 kHz (16 to 24 bits, PCM)
3.7V/3.7V
40 kilohms/20 kilohms
4 parallel Delta Sigma modulation
176.4 kHz (32 bits, PCM),
352.8 kHz (32 bits, PCM)

FormatCompatible cable
HS-LINK
Ver.1
Sampling
frequencies
Ver.2
BALANCED
Output voltage/
Output impedanceLINE
D/A converter
STEREO/MONO

Accuphase original standard
HS-LINK dedicated cable
32 kHz to 192 kHz (16 to 24 bits, PCM)
32 kHz to 384 kHz (16 to 32 bits, PCM)
2.5 V/50 ohms
2.5 V/50 ohms
4MDS+ principle/8 MDS+ principle

HS-LINKDigital
InputsAnalogInputsDigitalOutputAnalogOutputs

Supplied accessories● AC power cord(2 m (6.5'))

Frequency Response
THD + Noise
S/N Ratio
Dynamic Range
Channel Separation
Cutoff Frequency (Hz)/Frequency Step (Hz)Slope Characteristics (dB/octave)
Delay (Independent settings
for left/right possible)
Level Adjustment Range(Independent settings
for left/right possible)
Power Requirements
Power ConsumptionMaximum Dimensions
Mass

2 to 50,000 Hz (+0, –3 dB)
0.0006% (20 to 20,000 Hz)
HS-LINK/COAXIAL/OPTICAL
STEREO: 121 dB, MONO: 123 dB
BALANCED/LINE
STEREO: 117 dB, MONO: 118 dB
119 dB
110 dB (20 to 20,000 Hz)
0.1
10.0, 10.1, …, 99.9
1100, 101, …, 999
1000, 1010, …, 9990
1010.0k, 10.1k, …, 50.0k
0.1k
6, 12, 18, 24, 48*2, 96*3
–3,000 to +3,000 cm(converted into distance, 0.5 cm steps)–40 dB to +12.0 dB(0.1 dB steps)

Analog ATT OFF–50 dB to +2.0 dB
Analog ATT ON(0.1 dB steps)
120/220/230 V AC (voltage as indicated on rear panel), 50/60 Hz
33 watts(W×H×D) 465 mm (18.31”) × 151 mm (5.95”) × 396 mm (15.59”)
Net
15.1 kg (33.3 lbs)
In shipping carton
21 kg (47 lbs)

*2: Cutoff frequencies cannot be set between 10.0 Hz and 19.9 Hz.
*3: Cutoff frequencies cannot be set between 10.0 Hz and 31.4 Hz.

● Cleaning cloth

Remarks★ This product is available in versions for 120/220/230 V AC. Make sure that the voltage shown on the rear panel matches the AC line voltage in your area.
★ The 230 V version has an Eco Mode that switches power off after 120 minutes of inactivity.
★ The shape of the plug of the supplied AC power cord depends on the voltage rating and destination country.

●The specifications and appearance of this product are subject to change without notice.

https://www.accuphase.com/

F2403Y

850-2240-00（B1） PRINTED IN JAPAN