Introduction
XA100 Owner’s Manual
Analog designer Nelson Pass has over the years produced some truly great
Since the introduction in 1997, the X amplifier series using the patented Supersymmetry™ circuit topology have been the mainstay of amplifier offerings from Pass Laboratories™. These amplifiers are heavily biased Class A/B designs with only two gain stages and an absolutely minimal component count in the signal path. In spite of this simplicity and thanks to the unique characteristic of the X topology, these amplifiers achieve very high power with outstanding subjective and objective performance.
With the introduction of the XA100 Pass Laboratories™ significantly raises the performance standard of excellence by introducing an entirely new series of power amplifiers. The new “XA” series of amplifiers feature a refined and elegantly simple, very highly biased, pure Class A mode of operation. This is a new and unique circuit topology that we descriptively characterize as being
The emphasis of the XA series is to accentuate performance over power. The XA series has the characteristic warm midrange and sweet top end of the Aleph™ product conjoined with the extreme dynamic range and definitive bass control of the X series amplifiers.
The XA100 is packaged in an artistically refined variant of the massive chassis previously reserved for the 250 watt
The Pass Laboratories™ XA100 will deliver 100 watts rms into
8 ohms of impedance. This is the amplifiers class A limit, driving the XA100 harder or reducing the impedance of the load will not convey any additional power. Driving into a short will not convey any additional power. These are not design oversights or flaws in the XA100, but rather a condition of the very highly biased Class A operation. However; as an interesting point of reference, 100 watts driving a 87dB/1W/1m speaker will deliver in excess of 105 dB (quite loud) average acoustic signal in a 100 cubic meter room.
2
