Accuphase DP-11 (1989)

The DP-11 was Accuphase's compact disc player of December 1989. It used technology carried down from the company's top-of-the-line separate transport and processor components. It's a single-box player, but it has the parts of the flagship stack: 18-bit ladder-resistance D/A conversion, an 8× oversampling digital filter, and the champagne finish that marks the whole Accuphase line.

The converter section is the big part of this player. Accuphase used carefully selected 18-bit D/A converters with an 8× oversampling digital filter. The filter suppresses the region between 24.1 kHz and 328.7 kHz by -110 dB, and passband ripple is held to ±0.00005 dB. The audio low-pass is a discrete third-order Butterworth active filter (GIC) with an 18 dB/octave slope. Digital and analog sections are electrically isolated with four ultra-high-speed 40 Mbit/sec optocouplers per channel, and the internal circuits are shielded with thick metal plates. There are separate power transformers for the digital and analog stages, with independent left/right windings on the analog side.

The laser pickup rides a linear motor under 8-bit microprocessor control and can find a track in roughly a second. The whole mechanism sits on a floating aluminum die-cast frame to keep vibration and resonance out of the signal path. Accuphase's own literature puts the weight at "almost 14 kg," which made it one of the heavier CD players on the market at the time. The analog output stage is a DC-servo direct-coupled buffer with no gain. Level is handled digitally in 1 dB steps from 0 to -24 dB, adjustable from the supplied RC-4 remote. There's also a power-on play function that starts playback automatically when the unit is switched on, intended for use with a timer.

Connections include both balanced XLR and unbalanced RCA analog outputs, plus optical and coaxial digital outputs to EIAJ standards. The GaAlAs semiconductor laser reads the disc at constant linear velocity, 500 down to 200 rpm, with CIRC error correction. Accuphase's own advertising in the period positioned the DP-11 alongside the P-11 power amplifier and C-11 preamp as a matching system. HiFi-Stereo (January 1990, p.106) reported the DP-11 at ¥270,000 (about $1,875 at the time), listed with the P-11 and C-11 as the new Accuphase lineup at that show.

Documentation on the DP-11 is decent for a player of its age. An original information folder and a prospectus PDF survive. A few things remain unrecorded: no original retail price for the US market, no production end date, and no service or failure history in the sources we've been able to check.