SONY TA-F333ESL
¥ 85,000 (released in 1990)
Commentary
Stereo power amplifier using MOS FET as power element
It comes with a wireless remote control that can adjust the volume and select the source.
Electronic volume and electronic switch are not used to prevent deterioration of sound quality by using remote control. The volume is rotated by a small motor from inside, and the push-type function selector is rotated by a rotary switch installed inside.
In addition, the effect on sound quality is prevented by suspending the operation of the microcomputer except during operation.
Power MOS FET is used for the final transistor.
MOS FET has a wide safe operation region (ASO) and no secondary breakdown due to its negative temperature coefficient and high thermal stability in principle. It also has high-speed switching operation even at high current because it is a majority carrier device. In addition, because of its large input resistance, when used for power applications, the voltage amplification stage (A class stage) and power amplification stage (B class stage) can be separated in principle.
Two pairs of parallel push-pull power MOS FETs are used for a total of eight power MOS FETs.
The chassis uses an Acoustic Tuned G chassis (Acoustically Tuned Gibraltar Chassis) that pursues a vibration-free and resonance-free design from all angles including material and shape.
The G-chassis is made of calcium carbonate, the main component of marble, reinforced with unsaturated polyester and glass fiber. This material has superior vibration damping characteristics with greater internal loss than metals, and is also strong and capable of high-precision machining. In addition, this material is non-magnetic and non-metallic, so there is no electro-striction or eddy current induced by magnetic fields of transformers and condensers, etc., and from the electrical aspect, sound quality degradation is reduced.
The shape of the G chassis is designed with careful attention paid to acoustic characteristics. It has a very simple structure with no protruding parts. It eliminates partial resonance and split vibration that occur at the protruding parts. In addition, the thickness of each part of the chassis is sufficiently large, and the rigidity is increased by running ribs vertically and horizontally. In addition, the thickness of the ribs and the spacing between ribs are changed randomly so that there is no specific resonance mode.
The tote sink is made of vertical aluminum die-cast.
In addition, the front chassis, terminal panel, and case are fixed on the G chassis with connecting angles at important points to reinforce each other, thereby realizing a stronger chassis structure.
The S. T. D. (Spontaneous Twin Drive) power supply is used for the power supply section. In the S. T. D. power supply, the rectifier circuit of the power amplifier section is separated into A power supply for the A-class stage and B power supply for the power stage. This prevents interference between the A-class stage and the power stage at high output.
In the TA-F333ESL, A-class and B-class capacitors are arranged in a distributed manner, and the B-class capacitor is fixed with a vibration proof platform.
The power transformer has a double-shielded structure.
Equipped with an ES filter to prevent noise from the AC line.
The circuit configuration is simple with only two amplifier circuits, a phono equalizer and a power amplifier.
The power amplifier employs the S. L. L. (Super Legato Linear) method, which reduces the switching distortion and crossover distortion of the output stage in a wide band / wide dynamic range. This not only reduces the distortion factor at the effective output but also improves the distortion factor at the playback level in actual use.
The phono equalizer amplifier section for the MC cartridge uses a low-noise Hi gmFET that has excellent high-frequency response characteristics and eliminates TIM distortion.
The tone circuit uses a CR type. The effect does not change depending on the position of the volume, and a low-impedance design is possible. Therefore, the attenuator uses a low-impedance type that can improve the SN ratio at low volume.
A source direct switch is installed. With one touch of this switch, you can jump through circuits such as tone control, subsonic filter, balance and mode switch. This allows the input signal selected by the input selector to pass only through the attenuator and power amplifier before being output.
There is also a direct in jack that does not go through the input selector.
It has an adapter jack that is convenient for connecting a graphic equalizer or surround processor.
Use the switch on the front panel to switch between adapter use and normal use.
The pin jack terminals for CDs, Phono and Tuners are gold-plated to reduce contact resistance.
.JPG)
.JPG)
.JPG)
Model Rating
| Type | Pre-main amplifier |
| Effective output (20 Hz to 20 kHz) | 140W + 140W (4 Ω) 120W + 120W (6 Ω) 100W + 100W (8 Ω) |
| Output bandwidth | 10 Hz to 100 kHz (50W output, 0.02% harmonic distortion rate, 8 Ω) |
| Harmonic distortion factor | 0.0015% (8 Ω at 10W output) |
| Cross modulation distortion factor | 0.004% (at rated output, 8 Ω, 60 hz : 7 khz = 4 : 1) |
| Frequency characteristic | Phono MM : RIAA curve ± 0.2 dB Line system : 2 Hz ~ 200 kHz + 0 -3dB |
| Signal-to-noise ratio | Phono MM:87dB Phono MC:68dB Line system : 105 dB |
| Input Sensitivity / Impedance | Phono MM : 2.5mV/50k Ω Phono MC (40 Ω) : 170 μ V/1k Ω Phono MC (3 Ω) : 170 μ V/100 Ω Line system : 150mV/30k Ω |
| Output Level / Impedance | Rec out : 150mV/1k Ω Headphone : 25mW/8 Ω |
| Tone control | Bass : ± 7 dB (100 Hz) Treble : ± 6 dB at 10 kHz |
| Subsonic filter | 15 Hz or less, 6dB/oct. |
| Suitable speaker impedance | 4 Ω ~ 16 Ω |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 260W |
| External dimensions | Width 470x Height 165x Depth 435 mm Width with sidewood removed : 430 mm |
| Weight | 21.3kg |
| Attachment | Wireless Remote Control RM-J350 |