Accuphase DF-65 Digital Frequency Dividing Network

Multi-channel divider with fully digital signal processing realizes the ultimate in audio enjoyment with outstanding performance, sophisticated features and intuitive operation

The Digital Frequency Dividing Network DF-65 harnesses the very best of digital technology in every aspect, including a high-speed 40-bit floating point DSP. The standard unit configuration supports signal processing for up to four-way systems. Highly accurate digital filters offer a choice of 59 cutoff frequency points and up to 96 dB/octave attenuation. Integrated time alignment function adjustable in 0.5-cm steps, and delay compensator for automatically offsetting any filter circuit delays. Monophonic output mode provides high versatility for various configurations.

High-speed, high-precision DSP implements fully digital signal processing

Designed to serve as the core component of a multi-amped system, the channel divider DF-65 features high-speed digital signal processing with amazing power. Latest digital circuit topology and advanced technology come together in a floating-point DSP that has a 32-bit mantissa and 8-bit exponent section, serving as digital filter. The division into mantissa and exponent prevents errors even when handling very small values.

This results in dramatically improved dynamic range and superior precision, allowing very steep cutoff slope settings of 48 dB or 96 dB per octave. All other functions including phase, delay, and level control are also implemented in the digital domain. The result is ultra-precise filtering free from adverse effects by temperature changes or aging.

59 selectable cutoff frequency points

Filter frequency points can be set over the range from 31.5 Hz to 22.4 kHz in 1/6-octave intervals. In addition, 10, 20, and 290 Hz points are also provided, resulting in a total of 59 points. Each divider unit is fully flexible and allows independent selection of lower and upper cutoff frequency.

Six filter slope characteristics with up to 96 dB attenuation per octave

The filter attenuation characteristics can be set to 6 dB, 12 dB, 18 dB, 24 dB, 48 dB, or 96 dB per octave. The 96 dB/octave setting in particular allows the driver unit to reproduce only its intended frequency without being affected by adjacent frequency bands. This makes it possible to create a multi-amped system that takes musical accuracy to a wholly new level.

Specifications

Digital Inputs

COAXIAL

Format: IEC 60958/AES3 compliant

Sampling frequencies 32 kHz to 192 kHz (16 to 24 bits, 2-channel PCM)

OPTICAL

Format: JEITA CP-1212

Sampling frequencies 32 kHz to 96 kHz (16 to 24 bits, 2-channel PCM)

HS-LINK

Connector: RJ-45, HS-LINK cable

Ver. 1 Sampling frequencies 32 kHz to 192 kHz (24 bits, 2-channel PCM)

Ver. 2 Sampling frequencies 32 kHz to 384 kHz(32 bits, 2-channel PCM)

(352.8 kHz and 384 kHz are converted to 176.4 kHz and 192 kHz respectively.)

Analog Inputs

Maximum input level 3.7 V (1 kHz, 2.5 V output)

Input impedance

BALANCED: 40 kilohms

LINE: 20 kilohms

A/D converter

Principle: 1-bit delta sigma modulation

Sampling frequency: 176.4 kHz

Quantization: 24 bits

Digital Output HS-LINK Connector: RJ-45, dedicated HS-LINK cable

Frequency Response

2.0 to 50,000 Hz +0 -3 dB

D/A Converter

Quantization: 32 bits

STEREO operation: 4MDS++ type

MONO operation: 8MDS++ type

THD 0.0007% (20 to 20,000 Hz)

S/N Ratio

                              STEREO operation        MONO operation

COAXIAL/OPTICAL   121 dB                        123 dB

HS-LINK                  121 dB                        123 dB

Analog Input            116 dB                        117 dB

Dynamic Range 118 dB

Channel Separation 108 dB (20 to 20,000 Hz)

Slope Characteristics

6 dB/octave, 12 dB/octave, 18 dB/octave

24 dB/octave, 48 dB/octave, 96 dB/octave

*When cutoff frequency is 10 Hz: 48 dB/octave, 96 dB/octave not available

20 Hz: 96 dB/octave not available

Delay (converted into distance) 0 to ±3,000 cm (0.5-cm steps)

*Independent settings for left and right possible.

*Delay value range limit (absolute value) for all channels is 3,000 cm.

Level Adjustment Range "Analog ATT" OFF: -40 to + 12.0 dB (0.1-dB steps)

"Analog ATT" ON: -50 to + 2.0 dB (0.1-dB steps)

*Independent settings for left and right possible.

Output Voltage/Output Impedance

BALANCED: 2.5 V, 50 ohms, balanced XLR connector

LINE: 2.5 V, 50 ohms, RCA-type phono connector

Minimum Load Impedanc BALANCED/LINE 600 ohms

Power Requirements 120/220/230 V AC, 50/60 Hz

Power Consumption 31 watts

Maximum Dimensions

Width 465 mm (18.31")

Height 151 mm ( 5.95")

Depth 396 mm (15.59")

Mass

15.1 kg (33.3 lbs) net

21.0 kg (46.3 lbs) in shipping carton