Power Amplifiers

Pass Labs X1000.5 Monoblock Power Amplifier

ARTICLE INDEX

The Pass Labs X1000.5 Power Amplifier On the Bench

At 1 kHz, 5 volts into 8 Ohms, distortion was a paltry 0.005%.

pass-x1000.5-amplifier-1-khz-5-volts

At 20 volts (50 watts) output, distortion actually decreased (however, I consider this difference insigificant). Notice that the odd ordered harmonics predominate.

pass-x1000.5-amplifier-1-khz-20-volts

The B-A peak (1 khz) from using 19 kHz and 20 kHz sine waves as the test signal, was 95 dB below the fundamentals. Notice also that the base of the 19 kHz and 20 kHz peaks is relatively clean.

pass-x1000.5-amplifier-19-khz-20-khz

IMD at 50 watts output was 0.004%. This is terrific performance.

pass-x1000.5-amplifier-imd

THD+N vs. Frequency for a 50 watt output (8 Ohms) shows distortion staying below 0.02% to about 5 kHz, and a rise to just under 0.1% at 20 kHz.

pass-x1000.5-amplifier-thd-plus-n-vs-fr

THD+N vs. Power indicates that the X1000.5 outputs 1,000 watts into 8 Ohms at clipping (1% THD+N). In this graph, the 1% mark is crossed at about 950 watts, but this was due to the wall AC voltage dropping significantlly with such high power demand. There is no question that this amplifier will output at spec.

pass-x1000.5-amplifier-thd-plus-n-vs-power

The measured Frequency Response was 10 Hz - 20 kHz ± 0.1 dB.

pass-x1000.5-amplifier-fr