ART HD SERIES Graphic Equalizers


Applied Research and Technology (ART) introduced the new HD Series of professional equalizers. The HD filter sets uses precision 1-percent resistors and all active gain elements are ultra-low noise and low distortion, resulting in a total dynamic range specification of HD-215 > =120 dB and HD-131/231 > = 117 dB, making these equalizers compatible for all applications in which precision processing and silent operation are a priority.

The HD SERIES includes the HD-131, a single 31-band gaphic EQ; the HD-215, a dual 15-band graphic EQ; and the HD-231, a dual 31-band graphic EQ. Each individual filter band has a precision center frequency and constant Q response, which is narrow enough to prevent unnecessary interaction between filters, yet wide enough to create the exact natural-sounding audio response that the user requires. These equalizers use 20mm oil-damped precision slide potentiometers. making each slider extremely accurate and smooth. The HD SERIES equalizers incorporate independent variable highpass (low-cut) and lowpass (high-cut) filters. The highpass filter is useful for reducing power robbing, sometimes destructive low-frequency rumble, wind noise and AC hum. Having separate and variable precision control for both the highpass and lowpass filters allow the user to custom-tailor the audio signal.

The HD SERIES feature automatic relay bypass of audio and use a variable input level control, clip level indicator and selectable AC line voltage. Additional features include RFI filtering, selectable scale switching and active balanced I/O XLR and Euroblock connectors. A Bypass switch allows for direct comparison between the equalized and non-equalized signal for each channel.

The HD Series (HD131, HD215, HD231) will be available in August 2005. MSRP on the HD Series include HD131, $219; HD215, $219; and HD231, $359.

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