Accuphase DG 38 Brochure

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Call up cursor pad to select frequency and adjust level by moving cursor right and left or up and down. Fig. 1 DG-38 Block Diagram DG-38 Features Call up input panel for character input or editing Create your ideal listening environment with a stroke of the pen the Digital Voicing Equalizer makes this dream a reality. Separate sound field compensation (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. This somewhat unusual term was chosen to symbolize the advanced capabilities of 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 field compensation. 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 sound reproduction in the home environment can be significantly enhanced. Get ready to experience a new dimension of music enjoyment. What is a "Voicing Equalizer"? 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 to be taken into consideration. The Digital Voicing Equalizer DG-38 was created with this 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 program sources 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 the second is the EQUALIZER module that lets the user creatively and actively shape the sound field. These central DSP functions are handled by four 40bit floating point SHARC processors from AnalogDevices. The display of the DG-38 is a supremely large, wide- format color LCD that is configured as a touch panel. It lets you simply draw a desired frequency curve with the supplied stylus pen and immediately hear the results. Control of other functions is also easily 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 other digital Accuphase components such as the DP-100/DC-101, DC-330, DP-85, and DP-77 via the HS-Link interface. Analog components can be accommodated by installing suitable analog input/output option boards.Fully digital Voicing Equalizer with 40bit floating point DSP devices for digital signal processing. 192 kHz/24 bit input/output interface Two equalizing modules: sound field compensation (VOICING) and sound field creation (EQUALIZER) Large, wide-format color LCD panel (154 × 58 mm) Touch panel and supplied stylus pen Allows direct drawing of response curve on screen Cursor keypad can be called up for pinpoint operation and touchup Control functions by tapping or dragging symbols displayed on screen 20 memory slots to store entire patterns including target curve, pre-compensation curve, post- compensation curve, equalizer curve etc. Data sets can be given a name and called up or modified at any time. RS-232 connector for interfacing with a computer Sound field measurement microphone AM-28 supplied
Supplied Remote Commander RC-30 Controls input selector, equalizer on/off, memory recall, memory number up/down. Supplied stylus pen can be used to draw any desired response curve.

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Sound field compensation (voicing) Spectrum analyzerSound field creation (Equalizer) Configuration CONFIGURATION Two main circuit as- semblies with four high speed 40bit floating point DSP chips, Ultra Jitter-Free PLL circuit, tone generator, HS- Link en-coder/decoder, digital input/output connectors etc. The DG-38 has four main operation modes: "Voicing", "Equalizer", "Analyzer", and "Configuration". Four buttons on the front panel are used to select the respective mode. Because the DG-38 incorporates both measurement and adjustment functions, accurate sound field compensation can be carried out easily. 68 IIR type filters with 1/6 octave spacing are used for measuring the sound field, and the 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. 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 and Equalizer on/off condition and checking of right/left frequency distribution are also possible.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 the display screen. A cursor keypad is also available, for manually creating the curve or making adjustments. The values set using this screen are automatically read and applied by the digital filters. 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 field creation are separate, equalization can be further modified after the sound field compensation (voicing) curve has been established. 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.