LUXKIT A804/II
¥ 24,000 (released in 1982)
Commentary
A preamp kit of Lux Kit A800 series developed as an upgraded model of A804.
The A804/II is equipped with a duo-beta circuit and a tone control function.
A duo-beta circuit is installed in the equalizer amplifier section to improve the naked characteristics of the amplifier circuit and to improve the sound quality by combining an appropriate amount of NFB and DC servo.
All the discrete circuits are composed of low-noise, high-differential input by high mgFET, current mirror, cascode circuit, and output-stage SEPP.
The tone control is a CR-NF type using the NFB circuit of the flat amplifier.
In order to add this function, the basic amplifier circuit of the A804/II has been changed to a combination of FET differential amplifier and low-noise OP amplifier. When the tone control is in the defeat position, a flat frequency response can be obtained, and sound without noise variation or waviness is obtained.
Model Rating
| Type | Control amplifier |
| Output voltage | Rating : 1 v Maximum : 8 v |
| Total harmonic distortion factor | Not more than 0.006% |
| Frequency characteristic | 10 Hz to 200 kHz |
| Input sensitivity | Phono:2.2mV Tuner, Aux, Monitor : 150 mv |
| Input impedance | Phono : 50k Ω Tuner, Aux, Monitor : 65k Ω |
| Signal-to-noise ratio | Phono:80dB Tuner, Aux, Monitor : 100 dB |
| Tone control | Bass : ± 8.5 dB (300 Hz) Treble : ± 8.5 dB (3 kHz) |
| Attachment | Tape Monitor (1 system) Mode switch Attenuator |
| Power consumption | 13W |
| External dimensions | Width 290x Height 142x Depth 79 mm |
| Weight | 2kg |