PHILIPS AH280
¥ 80,000 (around 1980)
Commentary
A preamplifier of the slimline component series.
The equalizer amplifier consists of a low-impedance IC combined with a high-voltage, low-noise transistor to achieve a high S/N.
The circuit configuration is a differential output stage of class A SEPP configuration. It is not a DC amplifier without capacitors, but a DC amplifier that takes full advantage of load resistance.
By using a high-quality polypropylene condenser, the frequency characteristics and phase disturbance in the low frequency range are released, and quality at low volume is pursued.
Equipped with a low filter.
Equipped with an LGL transformer using low-noise transistors.
The tone control part uses a 4-series 21-step click type.
As an option sold separately, there was a special wood case with mahogany finish.
Model Rating
| Type | Pre-main amplifier |
| Circuit system | Equalizer amplifier section : first stage differential 3-stage direct connection, last stage A-class SEPP / DC amplifier configuration |
| Input / output terminal | Phono1/2, Mic, Tuner, Aux, Tape play1/2, Output1/2/3 |
| Harmonic distortion factor | 0.006% (20 Hz to 20 kHz) |
| Phono maximum allowable input | 240 mv (40k Ω) |
| Frequency characteristic | Phono (RIAA deviation) : 20 Hz to 20 kHz ± 0.5 dB Aux, Tuner, Tape : 10 hz to 200 khz -2dB Mic : 50 Hz to 20 kHz + 0.5 -3.0 dB |
| Signal-to-noise ratio | Phono:74dB |
| Scratch filter | 12dB/oct (-3dB at 7 kHz) |
| Tone control | Bass : + / - 10 dB Turnover Frequency : 250Hz/500Hz Treble : + / - 10 dB Turnover Frequency : 2.5kHz/5kHz |
| Subsonic filter | -12dB/oct |
| High filter | Mounted |
| External dimensions | Width 480x Height 68x Depth 340 mm |
| Weight | - |
| Sold Separately | Wood Case AH180 (¥ 16,000) |