Solid State (EMe power transistor) Stereo System "Shuhgetsu" series
120W Monaural Complimentary Parallel Push-Pull Power Amplifier and Preamplifier
- Full stage driven by regulated power supplies -
- Primary transmittal by Balanced Connection (Unbalanced RCA connectors provied, too) -
Negative Resistance Free (NRF) circuitry patented by Tetsuo Kawanishi, former associate professor at UEC Tokyo (The University of Electro-Communications), who designed this "Shuhgetsu" series amplifiers for SIBATECH.
Conventional high feedback amplifiers do not feed back perfectly. Such amplifiers eventually contain residual negative resistance where real part of impedance becomes negative in a certain high frequency range. A system containing negative resistance may oscillate or performs unsteadily resulting in producing excessive transient distortion to cause muddy the sound. When RF noise or the like gets mixed with such an amplifier, the system falls in further unstable conditions only to degrade sound quality.
In order to protect the circuit against this problem, ABIS "Shuhgetsu" amplifier is designed with NRF circuit to remove negative resistances generated in input and output impedances. As the result, original music signals are properly amplified. In addition, many high quality parts are used to enhance the quality of the circuit.
"Shuhgetsu" employs NRF regulated power supplies for both C-120 preamp and P-1120 power amp. Especially, the power supply built in the P-1120 mono block operates for both voltage amplifier stage as well as for power amplifier stage done first time in the world, so the power output 120W in actual feeling is equivalent to 240W from on-market products power amplifier stage of that are not operated on regulated power supply. Shuhgetsu therefore does not jeopardize transient response due to variation in output impedance that results in variations in power supply voltage.
The "Shuhgetsu" series consists of two mono blocks (Model P-1120 - 120W output each), preamplifier (Model C-120), and PSU (Model PS-120) for the preamplifier.
For more technical details, download 6 page pdf literatures. (Click here)
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Model P-1120
Power Amplifier (Mono) with built-in regulated power supply |
| Specifications |
| Max. Power Output |
120W(8 ohm /1kHz)/190W(4 ohm /1kHz) |
| T.H.D. |
Less than 0.1% (8 ohm /1kHz) |
| Frequency Response |
10~20,000Hz (-0.1dB/1W/8 ohm ) |
| Gain |
26.5dB |
| Input |
Balanced/Normal, Volume Control |
| Input Impeance |
Balanced 30k ohm Normal 50k ohm |
| Output |
Bi-Wiring |
| Size |
240W x 195H x 510D mm |
| Weight |
24 kg |
| Power Consumption |
200W (tested on 1/8IEC) |
| Power Source |
120V,220V, or 240V |
| Front Panel |
Acrylic plastic with laser processed art |
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Model C-120 & PS-120 PSU
Preamplifier (Stereo) and Regulated Power Supply |
| Specifications |
| Inputs |
LINE/NORMAL x 3 BALANCED x 1, PHONO x 1 |
| Gain |
Balanced 10dB, Normal 4dB, Phono 37dB |
| Max. Output Voltage |
7V |
| Frequency Response |
10~20,000Hz (±0.2dB) RIAA EQ (±0.3dB) |
| Input Impedance |
Balanced 50k ohm , Normal 30k ohm |
| Size |
360W x 193H x 332D (C-120), 120W x 193H x 320D (PS-120) |
| Weight |
10kg (C-120) , 6kg (PS-120) |
| Power Consumption |
15W |
| Power Soource |
120V, 220V, or 240V |
| Front Panel |
Acrylic plastic with laser processed art |
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