SANSUI AU-111

Commentary

The highest quality vacuum tube pre-main amplifier of Sunsui's Blackface No. 1.
It was released just around the time when vacuum tubes and transistors were replaced, and it was released as the last and highest quality vacuum tube pre-main amplifier.

6L6GC is adopted for the output tube, AB₁It is operated by PP fixed bias system.
In addition, flat characteristics are obtained over the whole band by the configuration of multiple negative feedback circuit.

The transformer uses ultra-wideband output and power transformer with low constant loss and excellent regulation. All of these transformers were guaranteed for life.

A 4-stage amplifier circuit including a cathode follower is used for the control amplifier section.
In addition, it is composed entirely of NF amplifier to suppress noise.

It is designed so that the preamplifier and main amplifier can be used independently.

It uses a tone control that can switch between the rising point and the falling point in a total of four steps, two low and two high.
It is also possible to defeat the high and low frequencies independently (tone circuit cancellation device).

In combination with SANSUI input transformer (A-603, A-604), it can be used even with low output MC type cartridge.

The head amplifier also uses a new type silicon transistor (micro-SEP).

The first stage of the intermediate amplifier uses a cathode follower circuit with high input impedance and low output impedance.

Two types of tape equalizers.

Low-impedance tape recording output terminal with cathode follower.

Low / high filter with CR feedback system.

Loudness control.

Two types of center output terminals, one for all band and the other for 3D system.

Presence control to improve the articulation of low frequencies.

It is equipped with accessories such as a tape monitor, phase switching, subvolume and headphone terminal.

Model Rating

Type	Pre-main amplifier
Rated output	Music Power (IHFM) : 96W Effective output : 45W/45W Stereo effective output (both channel operation) : 40W + 40W
Total harmonic distortion factor	0.8%
Intermodulation distortion factor (50 Hz to 5.5 kHz)	0.8%
Power Band With (IHFM)	20 Hz to 20 kHz (at 0.8%)
Frequency characteristic	AUX : 20 Hz to 50 kHz ± 1 dB
Hum and Noise (IHFM)	AUX:-80dB Phono:-70dB
Channel separation	Phono:45dB AUX:50dB
Residual noise	2 mv (8 Ω)
Load impedance	8 Ω, 16 Ω
Damping factor	15
Input Sensitivity / Impedance (Effective Output, 1 kHz)	Phono1 : 0.06mv/3.5 Ω (Using A-604) Phono2 : 0.2mV/30 Ω ~ 100 Ω (Using A-603) Tape Head (19cm/s 9.5cm/s) : 1.8mV/100k Ω Tuner, AUX, Tape Monitor : 220mV/500k Ω
Recording output (Pin cathode follower output)	100 times the Phono2 input 115 times the Tape Head input
Center channel output	1.5V/48k Ω (Effective Output)
Equalizer characteristics	Phono1, 2 : RIAA Tape Head : NAB (19cm/s, 9.5cm/s)
Preamplifier output	2.1V/710 Ω (Effective Output)
Tone control	Low : Defeat, 250 Hz, 500 Hz High : Defeat, 5 kHz, 2.5 kHz Bass(50Hz) + 11.5 dB to -10dB at 250 Hz + 16 dB to -14.5 dB at 500 Hz Treble(10kHz) 5 kHz : + 12.5 dB ~ -11dB + 7.5 dB to -6dB at 2.5 kHz
Loudness control (at Volume-30dB)	50 Hz : + 9.5 dB, 10 kHz : + 5 dB
High filter	20 kHz, -25dB, fo = 6 kHz
Low filter	20 Hz, -26dB, fo = 125 Hz
Semiconductors used	Vacuum Tubes (12 pcs) 6L6GC : 4 12AX7 : 5 12BH7A : 2 6AQ8 : 1 Piece Transistor 2SC-402 : 2 Diode (3 pcs) SW-0. 5a : 1 Piece SW-0. 5d : 2
Power supply voltage	AC100V/117V/240V, 50Hz/60Hz
Power consumption	280 VA (max)
External dimensions	Width 460x Height 170 (Excluding Rubber Feet) x Depth 345 mm
Weight	24.5kg