
A4-folded brochure for the DENON DTU-αS10, a satellite digital tuner for the now-forgotten CS-PCM format. The format itself was remarkable: the JCSAT-2A communications satellite broadcast 12 music channels across Japan at 48 kHz / 16-bit linear PCM with no compression (B-mode stereo), so quality above CD. The cover tagline reads “我々の宇宙には、CDを超越したデジタル・サウンドが存在する。” - “In our universe there exists digital sound that has surpassed CD.” Inside, the technical detail: the ALPHA processor (DENON’s proprietary technique that interpolates a 16-bit signal up to 20-bit quality), 20-bit S.L.C. with independent L/R channels, MSK demodulator and Viterbi decoder on new LSIs, two digital outputs (optical + coaxial) for recording onto DAT/MD/DCC, a copper-plated chassis with sintered-alloy insulators, and a 12-channel remote with 24 presets reserved for future expansion. Price ¥150,000 before tax, gold front panel in the S-series style, weight 12.2 kg. Today the unit is essentially a museum piece: MUSIC BIRD’s CS-PCM service launched in August 1992 and shut down on 31 July 2011, when descrambling chip production ended and the Broadcast Security Center was dissolved, leaving no point in building new tuners. So the DTU-αS10 is a monument to a short era when, in Japan, you could pull 12 channels of lossless music from a satellite for 600-800 yen per channel per month.
- ALPHAプロセッサー - ALPHA processor - DENON proprietary analog waveform reconstruction: a 16-bit signal is interpolated and reproduced at 20-bit quality
- 20ビット/S.L.C. - 20-bit S.L.C. (Super Linear Converter) with independent L/R channels, eliminating the zero-cross distortion typical of delta-sigma DACs
- MSK復調用IC + ビタビ復号LSI - MSK demodulator and Viterbi decoder on new highly integrated LSIs - the CS-PCM receiving stage
- デジタル出力2系統(光・同軸) - Two digital outputs (optical + coaxial) for digital-to-digital recording onto DAT, MD, DCC
- 有料放送デコーダ内蔵 - Built-in decoder for descrambling paid CS-PCM channels
- 銅メッキシャーシ - Copper-plated chassis, sintered alloy and aluminium composite insulators, Teflon pads and gold-plated terminals
| Model | Type | Price |
|---|---|---|
| DENON DTU-αS10 | CS-PCM stereo satellite tuner | ¥150,000 |

