The SDR-1000 Compact Disc Playback System
In January 1987, Spectral shipped its first digital product, the SDR-l000 Compact Disc Playback System, the result of four years of intensive investigation of digital audio issues. The SDR-1000 was the direct result of Dr. Keith 0. Johnson's lifetime engagement in recording technology design, and was the first product to directly attack the problems of CD sound by correcting in playback the errors inevitably introduced in the digital recording process.
The first complete design for a High-End American CD player.
The first conjugate correction filter programs to correct errors inherent in CD recording processes. The SDR-l000's three filter switches allow user selectable correction of the encoded phase errors. This unique flexibility allows the SDR-1000's performance to be matched to the specific characteristics of digital recordings from different manufacturers and different time periods.
The first and only digital playback system to employ Spectral's instrumentation design concepts, including: DC-to-megahertz analog response, push-pull balanced output circuits, Class A discrete topology, and modular card cage design.
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