SONY TA-FB720R
¥ 38,000 (released in 1998)
Commentary
A pre-main amplifier developed with the know-how of the ES series.
A power MOS-FET with excellent characteristics as an amplifier for audio is mounted on the final stage of the power section.
In addition, a fixed optical bias circuit is adopted, and an optical element with the same temperature characteristics as MOS-FET is inserted in the bias circuit to keep the idling current constant.
The power supply section is equipped with a torus and toroidal transformer.
This transformer improves the adhesion of the coil by making the cross section of the iron core of the core elliptical, and reduces the noise turbidity by reducing vibration.
The Advanced S. T. D. power supply is used for the power supply circuit, and the effect of voltage fluctuation is reduced by separating the power supply circuit for the voltage amplification stage and that for the power amplification stage.
New FB chassis with increased thickness of 1.2 mm is used for the chassis.
In addition, the beams passed back and forth in the chassis are enhanced to enhance the synthesis of the chassis as a whole.
The circuit board is mounted at a slightly inclined angle, suppressing the generation of standing waves in the chassis and greatly reducing resonance.
Simple and straight transmission is thoroughly implemented, the signal path is minimized, and a circuit design that does not use connectors as much as possible for wiring between internal blocks is implemented.
A source direct switch is installed and the tone control circuit and balance control circuit can be bypassed if they are not required.
It is equipped with a loudness switch that raises low and high sound according to human audibility at low volume.
Phono input circuit for MM cartridge is mounted.
Equipped with a subsonic filter to cut out unwanted low-frequency components caused by warping of analog records, etc.
Wireless remote control is included.
In addition to switching the main unit and adjusting the volume, this remote control can perform major operations on components such as Sony CD players and tuners.
.jpg)
.jpg)
Model Rating
| Type | Pre-main amplifier |
| Effective power (EIAJ) | 100W + 100W (4 Ω) 50W + 50W (8 Ω) |
| Input Sensitivity / Impedance | Phono MM : 2.5mV/50k Ω Line : 150mV/20k Ω |
| Output Level / Impedance | Rec out : 150mV/1k Ω Headset : 10 mW (8 Ω) |
| Total harmonic distortion factor | 0.008% (8 Ω at 10W output) |
| Intermodulation distortion factor (60 hz : 7 khz = 4 : 1) | 0.03% (8 Ω at rated output) |
| Frequency characteristic | Phono MM : 20 Hz to 20 kHz ± 0.5 dB Line : 7 Hz to 100 kHz + 0 -3dB |
| Signal-to-noise ratio | Phono MM:80dB Line:105dB |
| Tone control | Bass : ± 7 dB (100 Hz) Treble : ± 7 dB (10 kHz) |
| Accessory function | Source direct switch Tape monitor Loudness Subsonic filter |
| AC outlet | Power switch interlock : 2 systems |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 125W |
| External dimensions | Width 430x Height 150x Depth 405 mm |
| Weight | Approx. 8.6 kg |
| Attachment | Wireless Remote Control RM-S316 |