Technics SE-9200 Stereo Power Amplifier - Available at ProThrowbacks
Technics SE-9200 Orignal Cost $1,200
during 1975
Description thanks to Audio-database:
Stereo power amplifier which carries a 4 steps of Output-load-impedances change.
An Output load impedance can be switched to four steps, 0.08ohm (normal), 0.8ohm, 2.7ohm, and 8ohm. The circuitry serves as a bridge scheme without a gain transition.
A dumping factor is changeable with this Output-load-impedance change, and it is possible to pull out the performance of a speaker more and it becomes the numeration which is switched to 100, 10, 3, and 1 in the case of an 8-ohm speaker.
The circuitry of the power amplifier part is based on differential-amplification whole page hardwired-connection perfect complimentary OCL, and the work which realizes a low distortion and a high stability amplification everywhere is carried out.
While inserting the emitter-follower in the differential-amplifier following stage, increasing first rank amplification degree to it and improving an SN ratio, the impedance matching to the predrive stage was rationalized, and the distorted occurrence is prevented.
Moreover, in the predrive stage, while removing a bootstrap capacitor and raising low-pass stability, the stability of the output stage is also raised.
A power-source part adopts the constant-voltage regulated power supply of ±42V as the voltage amplification stage, and has adopted a mass transformer and a 10,000-micro F capacitor as an output stage.
The output Direct-reading peek detection type power meter is carried.
This meter can adjust three steps of meter range, and can read the movement toward an output in a higher precision.
The protection network original with technics by relay is adopted.
In this circuitry, relay contact resistance does not go into a signal system, and years of using does not have a tone-quality failure, either.
As a shocking noise insulator circuitry at the time of the power source ON, the zener diode of the common-emitter power source of a differential amplification, diode, the capacitor, and the timing circuit constituted from a resistor are carried.
Rating of a mode
FormStereo power amplifier
Effective outputA one side channel, 1kHz:110W/110W (4ohms)
83W/83W (8ohms)
Both channel, 1kHz:103W+103W (4ohms)
82W+82W (8ohms)
Both channel, 20Hz-20kHz:93W+93W (4ohms)
76W+76W (8ohms)
THD0.08%
Output bandwidth5Hz - -70kHz three dB (both ch(es), 8ohms)
Frequency characteristic5Hz-100kHz+0 -3 dB
SN ratio110dB
Remains noise0.3mV
Dumping factor4ohm: 50, 5, 1.5, 0.5
8ohm: 100, 10, 3, 1
Load impedanceMain or Remote: 4ohms - 16ohms
Main+Remote: 8ohms - 16ohms
Input sensitivity/impedance1V/40kohm
Power sourceAC100V, 50Hz/60Hz
Power consumption180W
DimensionsWidth 450x height 173x depth of 380.5mm
Weight15kg
during 1975
Description thanks to Audio-database:
Stereo power amplifier which carries a 4 steps of Output-load-impedances change.
An Output load impedance can be switched to four steps, 0.08ohm (normal), 0.8ohm, 2.7ohm, and 8ohm. The circuitry serves as a bridge scheme without a gain transition.
A dumping factor is changeable with this Output-load-impedance change, and it is possible to pull out the performance of a speaker more and it becomes the numeration which is switched to 100, 10, 3, and 1 in the case of an 8-ohm speaker.
The circuitry of the power amplifier part is based on differential-amplification whole page hardwired-connection perfect complimentary OCL, and the work which realizes a low distortion and a high stability amplification everywhere is carried out.
While inserting the emitter-follower in the differential-amplifier following stage, increasing first rank amplification degree to it and improving an SN ratio, the impedance matching to the predrive stage was rationalized, and the distorted occurrence is prevented.
Moreover, in the predrive stage, while removing a bootstrap capacitor and raising low-pass stability, the stability of the output stage is also raised.
A power-source part adopts the constant-voltage regulated power supply of ±42V as the voltage amplification stage, and has adopted a mass transformer and a 10,000-micro F capacitor as an output stage.
The output Direct-reading peek detection type power meter is carried.
This meter can adjust three steps of meter range, and can read the movement toward an output in a higher precision.
The protection network original with technics by relay is adopted.
In this circuitry, relay contact resistance does not go into a signal system, and years of using does not have a tone-quality failure, either.
As a shocking noise insulator circuitry at the time of the power source ON, the zener diode of the common-emitter power source of a differential amplification, diode, the capacitor, and the timing circuit constituted from a resistor are carried.
Rating of a mode
FormStereo power amplifier
Effective outputA one side channel, 1kHz:110W/110W (4ohms)
83W/83W (8ohms)
Both channel, 1kHz:103W+103W (4ohms)
82W+82W (8ohms)
Both channel, 20Hz-20kHz:93W+93W (4ohms)
76W+76W (8ohms)
THD0.08%
Output bandwidth5Hz - -70kHz three dB (both ch(es), 8ohms)
Frequency characteristic5Hz-100kHz+0 -3 dB
SN ratio110dB
Remains noise0.3mV
Dumping factor4ohm: 50, 5, 1.5, 0.5
8ohm: 100, 10, 3, 1
Load impedanceMain or Remote: 4ohms - 16ohms
Main+Remote: 8ohms - 16ohms
Input sensitivity/impedance1V/40kohm
Power sourceAC100V, 50Hz/60Hz
Power consumption180W
DimensionsWidth 450x height 173x depth of 380.5mm
Weight15kg