STATUS - SOLD
Click here for more pictures
Description :
The Passlab X150.5 stereo amplifier embodies the design technology and refinements of the “X” series amplifiers including extensions of the patented Supersymmetry circuit. In comparison to the immediate X150 predecessor, the X150.5 has significant improvement in sonic performance. The Supersymmetry circuit topology was granted a U.S. patent in 1994, and was the result of 19 years of effort by legendary analog designer and company founder Nelson Pass. Supersymmetry enhances the effect of negating distortion and noise at the output by providing a connection between the two halves of the balanced circuit. Any distortion and noise not already identical to the two halves is made more identical, and the result is improved noise cancellation at the output of the amplifier. 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% through a balanced connection without any additional effort. The Supersymmetry circuit delivers another 90% reduction, so that the X series has about 1/100 of the distortion of a conventionally simple amplifier. This gives good measured performance, which because a simple circuit produces it, 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.
The Passlab X150.5 amplifier has the tremendous dynamic range to do justice to the high-resolution digital recordings and the elegance to retrieve the micro dynamics offered by the most sensitive loudspeakers. The simple but powerful circuitry moves easily from total silence to explosive transient and back to silence without a trace and without information loss. Unlike conventional high power amplifiers, they provide this level of power with a subtlety befitting some of the better tube amplifiers. This performance is consistence across the audio spectrum and the amplifiers are unconditionally stable into all speaker loads. When tested, after amplifier has been played and heated up, the initial leanness in sound has slowly developed into warmth. It's almost tube like. Except the bass slam is something that no tube amplifier could hope to emulate. The top end has similarly sweetened - it's like honey. The imaging and the soundstaging of the Passlab X150.5 is of Mark Levinson standards but there is no 'hash' or 'haze' interfering with the music. It's like the music is coming from deep space. There is much more 'air' to the music and little details seem to be more easily heard. Though the mids and highs are tubelike, the sound is not laidback, instead it is neutral and transparent.
Specifications :
Gain................................................30 dB
Frequency response.........................-3 dB at 1Hz, -3 dB at 100 kHz
Power Output...................................150 Watts per channel
Maximum Output Voltage..................Plus, minus 50 volts
Maximum Output Current..................Plus, minus 20 amps
Input Impedance...............................22 kohm balanced
Damping factor.................................250 ref 8 ohms nominal
Slew rate.........................................plus, minus 50 V/uS
Output Noise...................................300 uV unweighted 20-20 kHz
Balanced CMRR..............................-60 dB at 1 kHz (input common mode rejection ratio)
DC offset.........................................< 100 mv differential
Power Consumption.........................250 watts idle, 600 watts maximum
Temperature....................................25 degrees C. above ambient at idle
Dimensions(w x d x h)......................48.5 x 49 x 18 cm
Weight............................................21 kg
Miscellaneous :
Made in...........................................USA
Condition.........................................8 / 10 (Decent condition)
Product information :
http://www.passlabs.com/pdfs/product%20manuals/x150_5-om.pdf (Online Manual)
http://www.enjoythemusic.com/magazine/manufacture/0808/
Reviews :
http://www.martinloganowners.com/forum/showthread.php?4988-Summits-c-w-Pass-X150.5-Amplifier (Forum Discussion) |
