Meridian Audio 808I manual The 808 Signature Reference CD Player, Digital Signal Processing

INTRODUCTION

The 808 Signature Reference

CD Player

The 808 Signature Reference CD Player takes Compact Disc playback to an entirely new level, with a heritage that includes the multiple award winning 508 and 800, and two dozen optical disc players from 1984 to the present day. The 808 is specifically designed as a CD-optimised machine, able to play virtually any CD, from conventional pressings to CD-R, CD-R/W, and discs of MP3 files (64–256kbps). It also plays the CD layer of an SACD disc.

At the heart of the 808 are fully-integrated electronics and a computer- style CD/DVD-ROM drive. The drive normally operates at standard CD speed, but is capable of much faster reading, using multiple high-speed re-reads to ensure accurate recovery of data from even the most difficult disc. This capability alone provides over ten times the error correction of a conventional CD player.

Digital Signal Processing

Once the digital data stream has been recovered from the disc, powerful on-board digital signal processing (DSP) with a capability of an impressive 150 MIPS (million instructions per second) up-samples the digital information from the 16-bit, 44.1kHz signal of conventional CD to a 24-bit signal with a sample rate of 176.4kHz. This signal is fed to the latest DVD- Audio quality delta-sigma digital to analogue converters to drive the analogue outputs, while a digital signal at an 88.2kHz sample rate is supplied to the digital outputs. Upsampling in this way enables filtering to take place far beyond the range of human hearing, as well as offering other audible benefits, right across the audio band, for ultimate transparency from a CD source.

The 808 employs a triple buffering system to minimise jitter, and therefore maximise HF transparency and stereo image precision and stability. This, and the digital electronics as a whole, are driven by a new design of high- stability clocking system which further reduces jitter and ensures that the highest level of detail is recovered from a disc. All digital data is accurately re-clocked.

Multiple power supplies ensure that digital and analogue circuitry are kept apart and can provide the required power when called upon to do so.

Integrated preamplifier

The 808i version of the 808 Signature Reference CD Player includes a built- in stereo preamplifier with the ability to handle six stereo analogue inputs, three digital coaxial S/PDIF inputs, and two Toslink optical digital inputs, making it ideal as the heart of a superb stereo system.

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