In 1997, Accuphase introduced a product that revolutionized the concept of the graphic equalizer and made headlines in the audio world: 

The DG-58 Digital Voicing Equalizer now raises the bar again. It is a 4th generation product that reflects the state of the art of advanced signal processing technology developed by Accuphase. Ease of operation has also been enhanced, with two “Simple Voicing” courses for automatic measurement and compensation, as well as a “Custom Voicing” course that gives users the power to realize a specific acoustic concept through extensive control over all aspects.

Most operations are controlled using the large, high-definition wide-format color LCD panel. This makes using the supplied stylus pen a pure joy, enabling the user to create any desired response simply by drawing on the screen. The DG-58 takes the concept of intelligent equalize

Warranty:

1-year manufacturer's warranty

Features:

• Fully digital signal processing Voicing Equalizer
• High-speed 40-bit floating point DSP
• Separate digital filters for Voicing and Equalizer sections 
• Wide-format color LCD panel allows direct drawing of response curve with stylus pen 
• Freely programmable 30 pattern memory 
• Real-time spectrum analyzer for the display of music signal and microphone input 
• Analog and digital inputs/outputs are provided as standard

Video Review:

Supplied Remote Commander RC-310
Controls memory save and recall, input switching, channel switching, VC/EQ selection, cursor activation, and more.

Supplied microphone AM-48

A dedicated sound field measurement microphone with controlled frequency response is supplied with the DG-58. The microphone is a 1/4-inch type back-electret condenser type with an ultra-thin and extremely small diaphragm, assuring linear response over a wide frequency range.

Setup screen for compensation mode and microphone parameters
The Voicing compensation mode (Auto/Manual) and compensation level and microphone level (measurement tone) are selected from this screen.

After Voicing, results can be checked on screen and by ear
The unit can display the response curve before and after compensation separately for each channel. It is also possible to compare the actual sound while playing music, by switching Voicing/Equalizer on and off.

Editing a sound field compensation curve
After checking the sound and the curve display, the user can return to the Voicing screen and make further adjustments at will.

Manual compensation
If automatic compensation leaves slight irregularities in the response curve, manual compensation in specific bands may bring the result even closer to a flat response.

Draw an equalizer curve based on
Voicing results After Voicing, the user can go to the Equalizer screen and further modify the curve.

Individual speaker measurement
This function is helpful for example to achieve proper level matching for the different frequency bands in a multi-amped system.

Equalizer with Wide Band Mode
In this mode, the cursor is expanded, allowing linked adjustment of 19 bands together for smooth curve creation

Technical Specifications: