Accuphase DC-330 (1999)
Digital preamplifier released in November 1999 with 24-bit MDS D/A conversion and support for high-resolution audio formats.
Overview
The Accuphase DC-330 is a precision digital stereo preamplifier manufactured by Accuphase Laboratory, Inc., originally known as Kensonic Laboratory, Inc. Released in November 1999, it was designed as a fully digital preamplifier featuring ultra-high-speed digital signal processing. Based on the DC-300, the DC-330 was engineered for ease of operation and readiness for emerging high-resolution formats such as SACD and DVD-Audio. It supports input sampling frequencies up to 192 kHz and 1-bit DSD at 2.8224 MHz with optional boards.
Specifications
| Release Date | November 1999 |
| Original Price | ￥880,000 |
| Input Format | 16–24 bit PCM up to 96 kHz; optional support for 176.4/192 kHz and 1-bit DSD at 2.8224 MHz |
| D/A Converter | 24-bit MDS format (six parallel ⊿Σ converters) |
| Frequency Response | 0.5 Hz to 50 kHz (+0, -3 dB) |
| Total Harmonic Distortion | 0.0006% (20 Hz–20 kHz) |
| S/N Ratio | 120 dB |
| Dynamic Range | 112 dB (24-bit input, LPF off) |
| Channel Separation | 108 dB (20 Hz–20 kHz) |
| Output Voltage / Impedance | Balanced: 5V/50Ω (XLR); Unbalanced: 5V/50Ω (RCA) |
| Volume Control | Speed-sensing rotation; Linear mode: -∞ to 99.5 (0.5 dB steps), Max DB mode: ∞ to +12.0 dB |
| Balance Control (DSP) | Adjustable difference: ∞, 4 to 0 dB in 1 dB steps |
| Tone Control (DSP) | Bass (315 Hz): ±5 dB in 1 dB steps; Treble (3.15 kHz): ±5 dB in 1 dB steps |
| Compensator (DSP) | Five settings with boosts at 100 Hz and 20 kHz |
| Attenuator (DSP) | -20 dB |
| Power Supply | 100 VAC, 50/60 Hz |
| Power Consumption | 25 W |
| Dimensions | 475 mm (W) × 150 mm (H) × 412 mm (D) |
| Weight | 20.2 kg |
Design
The DC-330 uses an ultra jitter-free PLL circuit to extract a high-precision master clock from the input signal and features a fully digital signal path with digital processing of volume, tone, balance, and compensator functions. Input signals are processed by an ultra-high-speed DSP, and the D/A converter is electrically isolated from the digital section via an 80 Mbps high-speed synchronized digital coupler. The MDS D/A converter employs six parallel ⊿Σ converters on a Teflon-based PCB with gold-plated copper foil. The analog output uses a fully balanced, ground-floating circuit with a third-order linear phase analog filter. The volume control uses a mechanical disk with radial slits on a large knob, designed to deliver an analog feel.
Market
Recent listings show the DC-330 selling for $3,999, PLN 7,950 (Sprzedajemy, Jan 2024), and CZK 175,000 (HifiOnline, Oct 2025). English brochures have sold for €10 on Kleinanzeigen (Nov 2025, Mar 2026).
eBay Listings
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