Pass Labs X5 Manual Do Utilizador

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X5 Owner’s Manual
The X5 five channel amplifier embodies the design technology and 
refinements of  the larger “X” series amplifiers including extensions 
of  the patented Supersymmetry circuit.
The Supersymmetry circuit topology was granted a U.S. patent in 
1994, and is the result of  19 years of  effort by Nelson Pass.  The 
amplifier uses highly matched components in a classically simple 
balanced Class A circuit.  The amplifier contains only two simple 
stages: the first is a balanced single-ended Class A voltage gain stage.  
Its output drives a bank of  high power Mosfets operated as voltage 
followers.  
These are inherently low distortion types of  circuits, but their 
performance is improved when operated in balanced mode through 
cancellation.  Distortion and noise identical to both halves of  a 
balanced circuit will disappear at the output, and in a well-matched 
symmetric circuit, most of  the distortion and noise is identical.
Supersymmetry enhances this effect by providing a connection 
between the two halves of  the balanced circuit that further perfects 
the match.  Any distortion and noise not already identical to the two 
halves is made identical, and the result is improved cancellation at the 
output.
Unlike feedback techniques where the goal is to correct for the 
distortion by feeding a gain stage an inversely distorted signal, 
Supersymmetry seeks merely to create perfect matching.
Matched balanced power circuitry typically sees a distortion 
and noise reduction of  about 90% (20 dB) through a balanced 
connection without any additional effort.  The Supersymmetric 
circuit delivers another 90% reduction, so that the X series has 
about 1/100 of  the distortion of  a conventionally simple amplifier.  
Actually this ordinary distortion and noise can still be seen at the 
output of  one half  of  the circuit, but since it is virtually identical 
on the other half, it goes away at the speaker terminals.  This gives 
good measured performance, which because it is simple, also sounds 
excellent.
Previously these kinds of  simple Class A circuits have been popular 
for their sound quality in low power amplifiers, but have not found 
application at high power levels due to excessive distortion and low 
efficiency.  Supersymmetry overcomes this barrier, delivering the 
sweetness, staging, and detail of  very simple circuitry up to kilowatt 
power levels and beyond.
Introduction