Sansui AU D907 top model amplifier in excellent condition

Description: For sale a beautiful one of the top models SANSUI model AU D907 integrated amplifier in excellent condition. Amplifiers all inputs work properly, no issues. The DC offset & BIAS were adjusted to the specs. Description (from website): For sale a top model SANSUI AU D907 amplifier in excellent, extremely clean condition. Amplifier works properly, no issues. The DC offset and BIAS were adjusted to the specs. DESCRIPTION (from website): DC pre-main amplifier equipped with Sansui's original diamond actuation circuit to improve dynamic distortion for live music playback. The equalizer, flat amplifier / tone control and power amplifier are all configured as push-pull output DC amplifiers with improved bare characteristics. In addition, in pursuit of sound quality, input capacitors for all block stages are eliminated, and a direct-coupled system with FET inputs for all stages is adopted to achieve pure music signal transmission and a wide range. All the FETs used are selected to have low-noise and high-gm characteristics. In addition, each block stage has a symmetrical circuit structure with symmetry, which greatly reduces harmful TIM distortion and envelope distortion and improves sound quality. The power amplifier section is a drive circuit with a power stage and 3-step amplification configuration. The first stage is an operation circuit with constant current using dual FET that allows large current to flow with low noise, the second pre-drive stage is a diamond operation circuit (PAT. PEND) with dual complimentary service that suppresses the generation of TIM distortion with powerful drive capability, and the third stage is a current operation push-pull circuit. The final power stage uses Sansui Custom NM (Non Magnetic) transistors, and the entire circuit is composed of symmetrical symmetrical circuits. The MC head amplifier is a target circuit using SANSUI's original push-pull input / output circuit. It is a direct coupled system. The first stage uses a newly developed low-noise, high-gm P-channel and N-channel multiple para-connected new-type FET. The independent power supply for the left and right channels realizes stable operation from minute input to large transient input. In addition, the target circuit configuration greatly improves the dynamic characteristics. The equalizer amplifier is a direct-coupled amplifier without the input capacitor, which affects the sound quality, and is equipped with a diamond drive circuit. The first stage is equipped with low-noise, high-gm, dual-FET operation input circuit, cascode bootstrap + constant current circuit, the second and third stages are equipped with diamond operation circuit + current operation push-pull circuit, and the output stage is equipped with SEPP circuit with Darlington connection to realize sufficient current margin and low output impedance. In addition, the target circuit configuration significantly improves dynamic distortion. The flat / tone amplifier is also a direct-coupled DC amplifier configuration. The first stage is an operation circuit with cascode connection and current source using dual FET of low noise and high gm, and the second stage is a current operation push-pull circuit with current mirror. Similar to the DC power amplifier section, it has an excellent configuration of open loop characteristics to reduce TIM distortion. You can also use the jump switch to jump directly from the equalizer amplifier to the power section. The power supply to the power amplifier section uses a high-regulation large toroidal transformer with two windings and two rectifier circuits with independent left and right channels of the power stage. The pre-drive stage uses an EI transformer with two independent power supply systems for left and right channels, for a total of four power supply systems. The MC head amplifier section and the DC flat amplifier section are independently supplied by a stabilizing power supply. Direct speaker output jacks. Two types of speaker systems can be connected : OFF, A, B, or A + B. Especially, the A system is connected directly to the DC power amplifier stage with the shortest distance without passing through the changeover switch. Features include a subsonic filter (16 hz, -3dB, 6dB/oct), audio muting (-20dB), tone jump switch, balance control, two circuit tape play / copy function, and input selector with indicator. The Phono input terminal is gold-plated. By separating the pre-main, the pre-amplifier section and the power amplifier section can be used independently. SPECIFICATIONS: Type - Wide-range DC pre-main amplifier Effective power - 100W + 100W (10 Hz ~ 20 kHz, THD 0.008%, 8 Ω) / 100W + 100W (1 kHz, THD 0.003%, 8 Ω) Total harmonic distortion factor - 0.008% or Less (10 Hz to 20 kHz, 8 Ω at Effective Output) Intermodulation distortion factor (70 hz : 7 khz = 4 : 1) - Not more than 0.008% Output bandwidth - 3 Hz ~ 70 kHz (IHF, double-channel operation, 1 kHz, 8 Ω) Damping factor - 100 (IHF, Double-channel Operation, 1 kHz, 8 Ω) Frequency characteristic - DC ~ 500 kHz, + 0 -3dB Input Sensitivity / Impedance (1 kHz) - 1V/47k Ω Signal-to-noise ratio - 125 dB or more (IHF, A-network, short circuit) Channel Separation (IHF, 1 kHz) - 95 dB or more Rise time - 0.5 μ sec Slew rate - ± 200 V / μ sec Preamplifier Section: Input Sensitivity / Impedance (1 kHz) - Phono-1MM : 2.5mV/47k Ω / Phono-1MC : 0.1mV/100 Ω / Phono-2MM : 2.5mV/47k Ω AUX, Tuner, Tape Play 1, 2 (PIN) : 150mV/47k Ω MC compatible impedance - 100 Ω or less Phono maximum allowable input (1 kHz) Phono MM:350mV(THD 0.01%) / Phono MC:30mV(THD 0.03%) Output Voltage (1 kHz) - Tape Rec1, 2 (at PIN, 47k Ω) : 150 mv Pre Out (at 47k Ω) : 1 V Max Pre Out (at THD 0.05%, 47k Ω) : 4 v Output Impedance (1 kHz) Tape Rec1, 2 : 600 Ω or less Total harmonic distortion factor Phono MC (1 kHz, 6 V) : 0.005% or less / Phono MM (20 Hz to 20 kHz, 6 V) : 0.005% or less AUX, Tuner, Tape Play 1, 2 (20 Hz to 20 kHz, 1 V) : 0.005% or less Intermodulation distortion factor (70 hz : 7 khz = 4 : 1) AUX, Tuner, Tape Play 1, 2 (1 v) : not more than 0.005% Frequency characteristic RIAA deviation (Phono 1, 2, 20 Hz-20 kHz) + / - 0.2 dB AUX, Tuner, Tape Play 1, 2 : 5 hz to 100 khz, + 0 -1dB Signal-to-noise ratio (IHF, A-network Short circuit) Phono MC (input conversion) : -154dBV Phono MM : 90 dB or more AUX, Tuner, Tape Play 1, 2 : 100 dB or more Channel Separation (IHF, 1 kHz) Phono MC : 70 dB or more / Phono MM : 75 dB or more AUX, Tuner, Tape Play 1, 2 : 80 dB or more Input-to-input separation (input short, 1 kHz) Tuner ⇔ Phono MM : 90 dB or higher Tape Play 1, 2 ⇔ Phono MM : 90 dB or more Tuner ⇔ Tape Play 1, 2 : 90 dB or higher Tape Play 1 ⇔ Tape Play 2 : 100 dB or more Tone control Bass : ± 6 dB (50 Hz) Tone selector (turnover frequency) : 300 Hz, 150 Hz Treble : ± 6 dB (15 kHz) Tone Selector (Turnover Frequency) : 6 khz, 3 khz Subsonic filter - 16 Hz (-3dB, 6dB/oct.) Headphone jack output - 120 mW (8 Ω) Load impedance 4 ~ 16 Ω External dimensions: Width 430x Height 168x Depth 428 mm Weight 20.8kg Check my other ads for more quality vintage electronics.

Price: 1295 USD

Location: Mississauga, Ontario

End Time: 2025-01-06T16:41:07.000Z

Shipping Cost: 90 USD