Sansui AU-217

 Clean, Low-Distortion Power

The AU-217 delivers 30 watts per channel min. RMS, both channels driven, into 8 ohms from 20 to 20,000 Hz, with no more than 0,06% total harmonic distortion. 

Circuit configuration in the AU-217 is a differential input with constant current source, followed by a current differential push-pull driver and, finally, a Darlington-arranged power output.  In the driver circuit,  the AU-217, which  is a Sansui exclusive, the advantages include low open-loop distortion and stability against voltage and thermal changes. The Darlington-arranged power output used in both the AU-217 has a low output impedance and features low distortion.

Rated Watts Available on Demand

As mentioned, Sansui uses musical inputs not only steady-state test signals, to test the AU prototypes. Design refinements are made after repeate auditions to ensure musicality. While your own ears can cartainly tell the difference, you might like to know that we have improved the sound by lowering TIM (Transient Intermodulation) distortion, reducing crosstalk and giving the Aus excellent transient response.

As a result, the rated watts on  AU-217  - 30 watts  - are guaranteed to be fully available on demand. What all this means can be understood by the following illustration.

Suppose there's a competitive amp with 30 watts RMS power which has the same specifications as does the AU-217. set the volume controls on at both amps at maximum position, feed both amps with a clipping level signal. A connected oscilloscopewill show clipped waveforms from both amps. Yetwhen a heavily modulated musical signal is applied, the AU-217 still sounds clean and clear, while the rival amp sounds distorted and harsh.  The reasons lie in the fact that the former has far rediced transient intermodulation distortion than the latter.

 Versatile Preamp Section

Precision Phono Equalizer

One of the most critical tasks required of a phono equalizer is precision. If phono signals are "colored" in the equalizer, no tone controls or other devices can ever restore tham to proper "flat" response. This is why we've used only the finest available  parts to give the phono equalizers in the AU-217  the ability to stay within ±0,5 of the RIAA equalization curve over the entire 30 to 15,000 Hz spectrum.

This model use PNO transistor inputs followed by a low-noise NPN transistor direct-coupled amp.fed with dual voltages from the power supply. High overload of 180 mV for the AU-217,  together with accurate RIAA equalization, let you enjoy dynamic unclipped record reproduction even at full power operation.

Bass/Treble NF Controls

The tone control circuit inn the AU-217  is located in the NF (Negative Feedback) network of the elaborate low-distortion power amp. This configuration features low distortion and high signal to noise, because all inputs - Aux, Tuner and Tape  - are sent direct to the power amp, (Phono equalizer output also goes direct to the power amp)

The Bass/Treble controls themselves have click stops for smooth and accurate use. Bass has a range of ±12 dB at 50 Hz Treble is ±11 dB at 15 kHz.

Effective High and Subsonic Filters

Scratchy records, hiss noise from tapes and any other high frequency noise is eliminated effectively without harming musical content since the High Filter on all this new AU models feature a sharp cut-off response of -6 dB/oct with a 3 dB attenuation at 7 kHz. If your phono cartridge has a high "Q" factor or resonance in the low frequencies, or if you want to play warped records without causing subsonic intermodulation, use the Subsonic Filter on the AU-217.

Loudness Switch

The human hearing mechanism becomes insensitive to the high and low ends of the audible spectrum as the level or volume of a sound decreases.  When listening to music at low levels switch in the Loudness circuit on your AU it boosts the lows and highs just enough to restore flat reproduction across the entire frequency range

Rugged Power Supply

Large transformers and electrolytic capacitors form the newly-designed power supplies in both models. The capacitors in the AU-217 are each 6,800 µF. These powerful supplies are located as far as possible from the phono equalizers to avoid hum pickup and assure accurate reproduction of musical input.

Low Profile Design

 The smart new looks of the Sansui AUs are practical too. Each component is designed to fit neatly into a standard EIA equipment rack (such as the Sansui GX-5) along with your Sansui cassette deck, the AX-7 Mixing Amplifier or the matching TU-217 FM/AM Tuner.

Other Features:

Left/Right Balance with Center Clock

Tape Monitor Switch

Stereo Headphone Jack

Large One-Touch Speaker Treminals

AC Outlets - Switched and Unswitched 200 watts each maximum

Specifications:

Power Output

Min. RMS both channels driven 20 - 20,000 Hz, no more than 0,06% T.H.D.:

30 watts per channel into 8 Ω

Min. RMS both channels driven at 1,000 Hz, no more than 0,06% T.H.D.:

37 watts per channel into 4 Ω;

34 watts per channel into 8 Ω

Load Impedance:  8 ohms

Total Harmonic Distortion:  less than 0,06% at or below rated min. RMS poer output

Intermodulation Distortion (70 Hz : 7,000 Hz = 4:1 SmPTE method)

Less than 0,06% at or below rated min. RMS power output

Damping Factor:  80 into 8 Ω

Frequency Response (at 1 watts):

Overall (from AUX):  10 to 50,000 Hz +0,5 dB , -1,5 dB

RIAA  Curve Deviation (30 to 15,000 Hz):  +0,5 dB  -0,5 dB

Input Sensitivity/ Impedance:

Phono :  2,5 mV/ 47 k Ω

Aux :  150 mV/ 47 k Ω

Maximum Input Capability:

Phono :  180 mV RMS

Output Voltage / Impedance:

Tape Rec (PIN):  150 mV into 47 k Ω load/ 300 Ω

Hum and Noise:

Phono :  76 dB

Aux :  94 dB

Channel Separation:

Phono :  65 dB

AUX :  68 dB

Controls

Bass :  +12 dB -12 dB at 50 Hz

Treble :  +11 dB -11 dB at 15 kHz

Filters

Subsonic :  -3 dB at 13 Hz (6 dB/oct)

High :  -3 dB at 7 kHz  (+6 dB /oct)

Loudness (volume control at -30 dB position):

=8 dB at 50 Hz

+6 dB at 10 kHz

AC Outlets:

Switched :  200 watts max

Unswitched :  200 watts total

Power requirement:

Power Voltage :  100, 120,  220, 240 V;  50/60 Hz

Power Consumption:  145 watts

Semiconductors:  30 transistors; 21 Diodes

Dimensions (W x H x D):  430 z 110 x 340 mm

Weight:  8,4 kg (18,5 ) NET