Marantz CM635 (circa 1998)

The Marantz CM635 is a combination CD/MD deck from the late 1990s. One component plays compact discs and records to MiniDisc, with one-button dubbing between the two formats. It was sold in Japan at ¥69,800 (around 1998) and came in gold and black finishes. The CM635 is closely related to the Marantz CM1040. The MiniDisc community notes the two "appear to be the same unit, with only styling differences," and the CM635 is sometimes described simply as similar to the CM1040.

Direct digital recording from CD to MD is the headline feature. Electronics Australia (1998) called the CM635 the first combo deck specifically designed for CD-to-MiniDisc dubbing, promising "an assurance of perfect copying every time." The deck has a built-in sampling rate converter that handles 32 kHz, 44.1 kHz, and 48 kHz inputs. It also has optical and coaxial digital inputs and outputs, a single analog input, and both analog and headphone outputs. A wireless remote is included. Synchro recording, 20-track programming, repeat, and random play modes are all present. The MD section uses ATRAC coding with a 1-bit D/A converter.

Electrical performance is respectable for the era. Both the CD and MD sections are rated at 20 Hz-20 kHz ±0.5 dB, with dynamic range of 93 dB or more, signal-to-noise ratio of 95 dB or more, and channel separation of 90 dB at 1 kHz. Harmonic distortion is listed at 0.01% for the CD section (one source gives 0.05% for the MD section). The unit draws 12W and measures 439 × 93 × 344 mm, weighing 5.2 kg.

Known specs:

- Frequency response: 20 Hz-20 kHz ±0.5 dB (both sections)

- Dynamic range: 93 dB or more

- S/N ratio: 95 dB or more

- Channel separation: 90 dB (1 kHz)

- Output: 2 Vrms; line input: 250 mVrms

- Dimensions: 439 × 93 × 344 mm; 5.2 kg

The record is thin on broader history. No explicit production years have surfaced, and repair documentation exists as a PDF, but no common failures or maintenance issues are documented beyond one owner noting a fading LCD display.