SANSUI AU-X11
¥ 275,000 (around 1982)
Commentary
This master integrated DC amplifier was developed in pursuit of the ideal form of i-Integrated Amplifier and by putting all sound technologies into it.
Super FF & diamond differential circuit is adopted for the power stage.
The Super FF system is a combination of NFB and feed-forward, and theoretically cancels any distortion generated in the power stage. The structure of this system is that the distortion is reduced by NFB, and the distortion component is extracted after the pre-drive stage by its distortion component detection function. The distortion cancellation signal is amplified by the error collection amplifier forming the feed-forward circuit in the same way as the red signal circuit, and the two signals are synthesized at the output. In addition, the summing point is matched by the adoption of accurate and stable summing network.
The diamond differential circuit has a structure in which transistors are arranged in the shape of a diamond, and the current margin of the drive stage can be made infinitely large to realize the high-speed response of the drive stage.
The equalizer amplifier uses a low-noise, high-gm dual FET and a diamond differential circuit to enhance sound quality.
In addition, a DC servo configuration is adopted.
The MC head amplifier section adopts a DC amplifier configuration of single-channel 14-stone FET and push-pull input / output power supply system exclusively for left and right sides.
In the power supply section, a large toroidal transformer for the power amplifier stage and a large EI transformer for the voltage amplifier stage are adopted. There are eight power supplies, power stage, pre-drive stage, flat amplifier / equalizer, and MC head amplifier completely independent on the left and right sides.
All copper plated chassis, NM elements, wood bonnet and copper plated screws are flux-free.
Model Rating
| Type | Master integrated DC amplifier |
| Effective output (10 hz to 20 khz) | 160W + 160W (8 Ω) |
| Total harmonic distortion factor (10 Hz to 20 kHz at effective output) | 0.004% or Less (8 Ω) |
| Output bandwidth (IHF, both channel operation) | 5 Hz ~ 100 kHz (8 Ω) |
| Frequency Response (1W) | DC ~ 300 khz + 0 -3dB |
| Signal-to-noise ratio | Phono MM:91dB Phono MC:77dB Tuner:110dB |
| Input Sensitivity / Impedance | Phono MC high : 85 μ V/30 Ω Phono MC low : 270 μ V/100 Ω |
| Maximum allowable input | MM:330mV MC:40mV |
| RIAA deviation (MM, rec out) | 20 Hz to 20 kHz ± 0.2 dB |
| High filter | 16 Hz (-3dB, 6dB/oct.) |
| Rated power consumption (Electrical Appliance and Material Control Law) | 400W |
| External dimensions | Width 515x Height 197x Depth 450 mm |
| Weight | 28.0kg |