LUXMAN SQ507X
¥ 86,500 (released in August 1971)
Commentary
Pre-main amplifier corresponding to the high power model of SQ505X.
The main amplifier section uses ± 2 power supply and all stages are directly connected without capacitor. The complimentary service stage uses pure output method combining PNP and NPN type power transistors to eliminate crossover distortion.
The previous stage consists of a two stage differential amplifier circuit to ensure stable operation.
The equalizer stage of the preamp section uses a new 3-stage direct connection circuit composed of PNP-NPN-PNP type transistors with high power utilization, and an emitter follower circuit is provided behind this stage to keep the input impedance of the Aux terminal high.
To reduce noise, we use ultra-low-noise transistors for all stages of the preamplifier section, and we use tantalum type and Mylar type coupling capacitors with low leakage current to reduce shock noise during switching.
The input impedance of the Phono1 terminal can be switched in three stages.
There is also a level set at the Aux connector.
Equipped with a low booster, high / low filter, and attenuator to increase the low frequency range.
The tone control is equipped with a curve point switch.
Model Rating
Type | Solid-state integrated amplifier |
Main Amplifier Section | |
Continuous output | 50W + 50W (8 Ω, both channels operating) 60W/60W (8 Ω, single-channel operation) |
Total harmonic distortion factor | 0.04% or Less (8 Ω, 50W) |
Cross modulation distortion factor | 0.04% or Less (8 Ω, 50W, 70 : 7 khz = 4 : 1) |
Output bandwidth | 5 Hz to 50 kHz -3dB (0.04%) |
Frequency characteristic | 10 Hz to 60 kHz (within -1dB) |
Input sensitivity | 580 mv (8 Ω, 50W) |
Input impedance | 50k Ω |
Damping factor | 40 (8 Ω) 80 (16 Ω) |
Residual noise | 1 mV or less |
Preamplifier Section | |
Frequency characteristic | 10 Hz to 50 kHz -3dB (Aux1) |
Total harmonic distortion factor | 0.05% or Less (1 kHz, 1 V, Aux1) |
Input sensitivity | Phono1, 2 : 2 mV Aux1 : 90 mV or more (adjustable) Aux2, 3 : 80 mv |
Input impedance | Phono1 : 30k Ω, 50k Ω, 100k Ω Phono2 : 50k Ω Aux1 : 50k Ω Aux2, 3 : 200k Ω |
Signal-to-noise ratio | Phono1, 2 : 63 dB or more Aux1, 2, 3 : 80 dB or more |
Maximum Allowable Input (1 kHz) | Phono:300mV |
Tone control | LUX System NF Type with Bending Point Switching Low Bend Point : Defeat, 150 Hz, 300 Hz, 600 Hz High Frequency Curve Point : Defeat, 6 kHz, 3 kHz, 1.5 kHz |
Residual noise | 25 μ V or less |
Crosstalk (1 kHz) | Phono : -60dB or less Aux : -65dB or less |
Filter | Low-cut : 70 Hz (-6dB/oct.) High Cut : 6 kHz (-6dB/oct.) |
Low booster | 100Hz(6dB/oct) |
<General> | |
Attachment | Attenuator (-18dB) Speaker switch (2 systems) Premain isolation switch Tape monitor (2 systems) Recording output terminal (2 systems) |
Semiconductor used | Transistor : 33 Diode : 2 pcs Varistor : 4 pcs |
Power consumption | 200W (8 Ω simultaneous load at maximum output) |
External dimensions | Width 450x Height 160x Depth 268 mm |
Weight | 11kg |