SANSUI CA-F1

Commentary

A thin DC preamplifier using a diamond differential circuit and toroidal transformer.

Uses MC head amplifier.
The circuit configuration employs a symmetrical circuit with push-pull input and push-pull output. It also adopts a symmetrical circuit which is further advanced from the symmetrical circuit and the parallel connection of low-noise, high-gm P-channel and N-channel FET developed by SANSUI for the first time, and symmetrical circuit which is further advanced from symmetrical circuit.
In addition, stable operation is achieved by independent power supply for left and right channels.

It uses a monophonic construction configuration, and each block is a symmetrical circuit with independent left and right arrangements.
Furthermore, in order to improve separation and crosstalk, left and right independent wafers are used for switches.
Furthermore, in pursuit of high-quality sound, we use not only patterns on circuit boards but also jumper with lead wires that allow sufficient current to flow.

A newly developed thin toroidal transformer is used for the power supply section.

The equalizer amplifier section has a DC configuration with a direct-coupled diamond differential circuit.
The first stage has good pair characteristics and employs a low-noise, high-gm, dual-FET differential input circuit, and a cascode bootstrap circuit that is not affected by input impedance.
A high-performance constant-current circuit (PAT. PEND) composed of a two stage direct-coupled circuit of NPN-PNP transistors provides high CMRR (common-mode suppression ratio) at the summing point and excellent dynamic characteristics are obtained.
The second and third stages are diamond differential circuit + current differential push-pull with excellent drive capability, and the output stage is SEPP circuit with Darlington connection with sufficient current margin. The low-output impedance and low-impedance NF circuit design provides sufficient dynamic range for load impedance changes and improved SN ratio.

A direct-coupled DC configuration is adopted for the flat amplifier and tone amplifier without input capacitor.
The first stage is a newly developed low-noise, high-gm dual-FET cascode connection and differential circuit with constant current, the second stage is a current differential push-pull circuit with current mirror, and the output stage is a SEPP configuration with two stage Darlington connection.
The tone control circuit is a highly variable NF type with a tone defeat switch for when the tone control function is not required.

Equipped with a subsonic filter, loudness switch, balance control, 2-circuit tape play function, power selector (B, A, OFF), power switch with indicator, earth terminal, etc.

EIA-standard rack-mount adapter is included.
Also, there was a real wood Shiraki (fabric color) wood case with a plug material sold separately.
This case has an open pore finish that is resistant to aging.

Model Rating

Type	DC preamp
Input Sensitivity / Impedance (1 kHz)	Phono MM : 2.5mV/47k Ω Phono MC : 0.1mV/10 Ω AUX, Tuner, Tape Play1, 2 (PIN) : 150mV/47k Ω
Maximum Allowable Input (1 kHz)	Phono MM(THD 0.008%):350mV Phono MC(THD 0.03%):24mV
Output Voltage (1 kHz)	Tape Rec1, 2 (PIN) : 150 mv (at 47k Ω) Pre Out : 1 V at 47k Ω MAX Pre Out (THD 0.005%) : 10 V at 47k Ω
Output Impedance (1 kHz)	Tape Rec1, 2 (PIN) : 600 Ω or less Pre Out : 600 Ω or less
Total harmonic distortion factor	Phono MM (20 Hz to 20 kHz at 6 V) : 0.005% or less Phono MC (at 1 kHz, 10 V) : 0.005% or less AUX, Tuner, Tape Play1, 2 (20 Hz to 20 kHz at 10 V) : 0.005% or less
Intermodulation distortion factor (70 hz : 7 khz = 4 : 1)	AUX, Tuner, Tape Play1, 2 at 10 v : not more than 0.005%
Frequency characteristic	Phono MM (RIAA deviation) : 20 Hz to 20 kHz ± 0.2 dB Phono MC : 20 Hz to 20 kHz ± 0.2 dB AUX, Tuner, Tape Play : 5 hz to 600 khz + 0 to 3 db
Signal-to-noise ratio (IHF, A-network Short circuit, pre-out)	Phono MM : 90 dB or more Phono MC (10 Ω short circuit) : 75 dB or more AUX, Tuner, Tape Play1, 2 : 110 dB or higher
Input reduced noise (A network, short circuit)	Phono MM:-142dBV Phono MC:-155dBV
Channel separation (IHF, Pre out)	Phono MM (1 kHz) : 85 dB or more (10 kHz) : 75 dB or more Phono MC (1 kHz) : 75 dB or more (10 kHz) : 70 dB or more AUX, Tuner, Tape Play1, 2 (1 kHz) : 88 dB or more (10 kHz) : 80 dB or more
Input-to-input separation (Input short, 1 kHz, Pre out 1 V)	Tuner ⇔ Phono MM : 85 dB or higher Tape Play1, 2 ⇔ Phono MM : 85 dB or more Tuner ⇔ Tape Play1, 2 : 85 dB or higher Tape Play1 ⇔ Tape Play2 : 85 dB or more
Tone control	Bass : + 7 dB, -9dB (50 Hz) Treble : + 7 dB, -7dB at 15 kHz
Subsonic filter	16 Hz (-3dB, 6dB/oct.)
Loudness (Volume -30dB)	+ 9 dB at 50 Hz, + 5 dB at 10 kHz
Rise time	0.6 μ sec
Rated power consumption (Electrical Appliance and Material Control Law)	35W
External dimensions	Width 430x Height 60x Depth 435 mm With Rack-mount Adapter : Width 482 mm
Weight	6kg With Rack-mount Adapter : 6.1 kg
Sold Separately : Wood Case CW-1 (¥ 10,000)
External dimensions	Width 524x Height 71x Depth 406 mm