PHILIPS RH521
¥ 116,000 (around 1972)
Commentary
A pre-main amplifier that meets the German Industrial Standard (DIN) HiFi specification 45500.
The power amplifier section is designed to increase the bias current, so that notching and crossover distortion are reduced even when the signal is small.
Equipped with a speaker matrix circuit, 4-channel playback is possible.
In addition to the normal tone control, it is equipped with a presence control to adjust the middle range.
Model Rating
| Type | Pre-main amplifier |
| Rated output | 30W + 30W (4 Ω) |
| Music power | 40W + 40W (4 Ω) |
| Harmonic distortion factor | 0.1% or Less (20W + 20W) |
| Cross modulation distortion factor | 1% or Less (250 Hz to 8 kHz) |
| Crossover distortion | 0.01% or less |
| Power Band Width | 15 Hz ~ 30 kHz -3dB (1% distortion) |
| Frequency characteristic | 15 hz ~ 40 khz + 0. 5-3 db |
| Signal-to-noise ratio | -90dB or more (30W + 30W) |
| Crosstalk | -45dB or more (1 kHz) |
| Damping factor | 20 or More (4 Ω) |
| Input Sensitivity / Impedance (1 kHz at 30W output per channel) |
Phono : 2mV/50k Ω (DIN5P) Tuner : 100mV/100k Ω (DIN5P) Recorder, Monitor : 250mV/100k Ω (DIN5P) Auxiliary Terminal : 100mV/750k Ω (DIN5P) Mic : 1mV/2k Ω (DIN5P) |
| Output terminal | DIN speaker connector : 2 (4 Ω ~ 8 Ω) DIN headphone connector : 1 (8 Ω ~ 600 Ω, taken out from front panel) |
| Rumble filter | 12dB/oct (-3dB at 80 Hz) |
| Scratch filter | 12dB/oct (-3dB at 7 kHz) |
| Tone control | Bass : ± 14 dB (50 Hz) Treble : + 14 dB ~ -16dB (10 kHz) |
| Loudness control | 3-step switching |
| Presence control | ± 6 dB at 2 kHz |
| Power consumption | 55W ~ 125W |
| External dimensions | Width 470x Height 117x Depth 280 mm |
| Weight | - |