Power output with 1kHz test signal
- 8-ohm load at 1% THD: 312W
- 8-ohm load at 10% THD: 427W
- 4-ohm load at 1% THD: 632W
- 4-ohm load at 10% THD: 844W
The Luxman B-1000f is a high-power solid-state mono power
amplifier and the flagship of the Luxman line.
Chart 1 shows the frequency response of the amp with
varying loads. The high-frequency response is moderately wide with an approximate -3dB
point of about 90kHz. Output impedance, as judged by the closeness of spacing between the
curves of open-circuit, 8-ohm, and 4-ohm loading, is very low in the audio band and
beyond. The usual NHT dummy-load curve is not shown, as the variations in the response
would not show.
Chart 2 illustrates how total harmonic distortion plus
noise vs. power varies for 1kHz and SMPTE IM test signals and amplifier output load.
Amount of distortion is low right up to clipping -- the behavior of most solid-state power
amplifiers. This particular design has an enormous power supply and super-beefy output
stage and is said to put out 2kW into 1-ohm loads. I have no doubt that it can.
Total harmonic distortion plus noise as a function of
frequency at several different power levels is plotted in Chart 3 for 4-ohm loading. As is
usual for all but a very few amplifiers, the distortion does rise at high frequencies,
above around 500Hz.
Damping factor vs. frequency is shown in Chart 4 and is of
a very high value at low frequencies and typical of many solid-state amplifiers, being
high at low frequencies and rolling off with increasing frequency starting at some 200Hz.
Still, for this amplifier, the damping factor is greater than 100 at 20kHz.
The spectrum of AC-line and test signal-harmonics shown in
Chart 5 for a 10W 1kHz test signal into 4 ohms has low amounts of AC-line harmonics.
Signal harmonics of second, third, fourth, and fifth order are visible at very low
magnitudes, the second being the highest at only 0.001%.