Ево нађох још један детаљан тест "Yamаha A-S1200", па нека прокоментарише свако ко разуме дијаграме и резултат тестова боље од мене...
Yamаha A-S1200 Laboratory
According to company information, the A-S1200 achieves 90 watts into 8 ohms and 150 watts into 4 ohms. As always, we get more: 110 W into 8 Ω and 191 W into 4 Ω with one channel driven.
Driving two does not make an impression on the power supply at 8 Ω (2 x 110 W), at 4 Ω it is, but the "gain" from the lower impedance is still clear (2 x 172 W). These results are similar to those obtained by the Sphinx 3, but this time not from impulse terminals, but from classic, linear AB class circuits.
Like Technics, Yamaha pedantically adheres to the 200 mV sensitivity standard - exactly this voltage applied to the amplifier's inputs will translate into the rated power.
In view of such sensitivity, the noise ratio deserves recognition, S / N is 87 dB. The frequency response (Fig. 1) is excellent, with no dip at 10 Hz, just -1 dB at 100 kHz and 8 Ω, and -1.5 dB at 4 Ω.
The harmonic spectrum (Fig. 2) is no longer perfect, the odd ones have the advantage, the strongest third is -70 dB, the fifth is -80 dB, and the seventh is one decibel lower; you can also see even ones - the second one at -76 dB and the fourth one at -79 dB. Therefore, THD + N (Fig. 3) is not as low as, for example, in the H95, but the characteristics are still good, below 0.1% we go down with power above 2 W for 8 Ω and 4 W for 4 Ω.
The power indicators work accurately (at low power) and very accurately (at high power), when the A-S1200 indicates 1 W, we actually have 0.9 W, and when 100 W - 100 W.
Иначе, моје кутије су на 4Ω, 150W.