Pass Labs XA100 Manual Do Utilizador

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XA100 Owner’s Manual
Analog designer Nelson Pass has over the years produced some 
truly great solid-state amplifiers, each unique in it’s own way.  Not 
surprisingly, the Pass Laboratories ™ XA100 monoblock amplifier 
is no exception. The XA100’s sleek industrial design is a stunning 
understatement of  artistic form integrated with state of  the art 
function.
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 
Single-ended Class A. This new topology combines the very best 
characteristics of  Pass Laboratories™ “X” series amplifiers and the 
highly rated “Pass Laboratories Aleph™”.  The XA series is the 
marriage of  a highly refined Aleph™ output stage with the patented 
Supersymmetry™ “X” front end.
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 X-250.5 stereo 
amplifier, but running more than twice the Class A bias current of  
our other amplifiers. 
 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.
Introduction