DIATONE DA-U1000
¥ 118,000 (around 1982)
Commentary
Pre-main amplifier of DIATONE by SANSUI OEM.
The NFB circuit, which tends to cause TIM distortion, has been fundamentally revised, and a new circuit design in which a feed-forward circuit and an NFB circuit are combined to make it possible to theoretically reduce any distortion generated in the power stage to 0.
On the material side, magnetic strain is eliminated by adopting copper plated chassis and using a large amount of non-magnetic elements.
In addition, a heat pipe is used to form a construction that avoids magnetic flux.
The power supply section uses a large power transformer that is independent of L/R and stage, and a high-speed, ultra-low magnification capacitor.
Newly developed equalizer circuit is adopted.
Equipped with MC head amplifier capable of switching between 2 positions and gain.
Model Rating
| Type | DC pre-main amplifier |
| Power Amplifier Unit | |
| Effective output (10 hz to 20 khz, THD 0.003%) | 100W + 100W (8 Ω) |
| Total harmonic distortion factor (10 kHz to 20 kHz, effective output) | 0.003% or Less (8 Ω) |
| Intermodulation Distortion Factor (60 Hz : 7 kHz = 4 : 1, SMPTE) | 0.003% or Less (8 Ω) |
| Output Bandwidth (IHF, both channel operation, THD 0.02%) | 5 Hz ~ 80 kHz (8 Ω) |
| Damping factor (new IHF) | 100 (8 Ω, 20 Hz to 20 kHz) |
| Frequency Response (1W) | DC ~ 300 khz + 0 dB -3dB |
| Equalizer Amplifier Section | |
| Input Sensitivity / Impedance (1 kHz) | Phono1, 2 mm : 2.5mV/47k Ω Phono1, 2 mc : 100 μ V, 300 μ V/100 Ω Tuner, Aux, Tape play1, 2 : 250mV/27k Ω |
| Phono maximum allowable input (1 kHz, THD0.01%) | MM:200mV MC:25mV |
| Output Voltage / Impedance (1 kHz) | Tape rec (PIN) : 250 mv (47k Ω) / 600 Ω |
| Total harmonic distortion factor (20 Hz to 20 kHz, 5 v output) | Phono MM : not more than 0.005% Phono MC : not more than 0.006% |
| RIAA Deviation (MM, Rec out) | 20 Hz to 300 kHz ± 0.2 dB |
| Signal-to-noise ratio (A network, short circuit) | Phono1, 2 mm : 90 dB or more Phono1, 2 mc : 74 dB or more Tuner, Aux, Tape play1, 2 : 110 dB or higher |
| Channel Separation (1 kHz) | Phono1, 2 mm : 60 dB or more Phono1, 2 mc : 50 dB or more Tuner, Aux, Tape play1, 2 : 80 dB or more |
| <General> | |
| Pwer | 100 VAC, 50Hz/60Hz |
| Rated power consumption (Electrical Appliance and Material Control Law) | 250W |
| External dimensions | Width 460x Height 160x Depth 404 mm |
| Weight | 14.7kg |