This newly restored vintage Sansui AU-999 was Sansui’s flagship integrated amplifier of the early 1970s, a true statement piece in their legendary lineup. Rated at 50 watts per channel into 8Ω (70W into 4Ω), it delivers a powerful yet refined sound with exceptional musicality.
Designed with a fully direct-coupled circuit, precision triple-tone controls (Bass, Mid, Treble with selectable turnover points), and dual phono inputs, the AU-999 was built for serious listening. Its warm, organic midrange and smooth clarity made it a favorite among discerning audiophiles, while its versatile input options and pre/power separation switch ensured it could anchor even the most ambitious HiFi systems.
With its solid build, brushed aluminium faceplate, and classic Sansui layout, the AU-999 embodies the golden era of Japanese HiFi design. Today, it is sought after for both its musical character and its collector’s value—a vintage amplifier that remains every bit as engaging as when it first left the factory floor in Tokyo over 50 years ago.
Sansui AU-999
The AU-999’s preamp features low-noise PNP silicon transistors and an advanced direct-coupled topology for lifelike dynamics and musicality. Triple tone controls enable precise shaping of bass, midrange, and treble. It includes dual phono inputs with adjustable load, two tape loops with Tape-to-Tape dubbing, and a muting/level/tracking circuit for careful listening adjustment.
When Sansui released the AU-999 in 1970, it was intended as a true flagship integrated amplifier—pushing beyond the already respected AU-777 series. Its design shows the blend of engineering precision and audiophile focus that marked Sansui’s golden era.
1. Direct-Coupled Circuitry
The AU-999 used a fully direct-coupled amplifier stage (no output capacitors), which gave it greater speed, extended low-end response, and reduced phase shift compared to capacitor-coupled predecessors.
This was state-of-the-art for its time, putting Sansui on par with high-end Western amplifiers.
2. Triple Tone Control System
- Separate Bass, Midrange, and Treble controls with selectable turnover frequencies.
- Each control works in click-stop increments, allowing precise and repeatable adjustments.
- This made it highly versatile, adaptable to different room acoustics and speaker pairings.
3. Advanced Preamp Section
- Two phono inputs for multiple turntables, plus a dedicated microphone input.
- Built with low-noise PNP silicon transistors in a three-stage differential configuration.
- Wide frequency response: 20Hz – 70kHz in preamp stage, giving vinyl playback remarkable openness.
4. Connectivity & Flexibility
- Multiple line inputs (Tuner, Aux, Tape) with tape-to-tape dubbing capability.
- Preamp / Power amp separation switch, allowing the AU-999 to act as either a dedicated preamp or power amp.
- Three speaker outputs (A, B, C) selectable via front panel.
- Front-panel headphone jack for private listening.
5. Build & Aesthetics
- Classic brushed aluminium faceplate with Sansui’s distinctive early-70s layout: symmetrical knobs, toggle switches, and large volume/balance controls.
- Solid steel chassis with careful internal layout to minimize noise and crosstalk.
- Weight: approx. 17.5 kg, giving it the feel of a serious, no-compromise amplifier.
6. Additional Features
- Muting switch to reduce signal instantly without altering volume.
- High/Low filters to tame unwanted noise or rumble from records.
- Balance check switch to quickly test channel output.
- Click-stop attenuator volume control, ensuring precision adjustment at all levels.