PASS LABS X-3 channel power amplifier
You don't see this one often. 150 watts/channel in a three channel amplifier. It is identical to the X-150 but with an extra channel. Ideal for an audiophile Home theater system to get great center channel sound along with your front speakers. I actually used it as center and rear with the XA60.5 mono amps (that I am also selling on Audiogon in a separate listing). Listed as an 8 by Audiogon guidelines because I am the second owner. Wonderful condition and wonderful sound!
You can contact me at 614-256-1755 or through Audiogon messaging with any questions. Many more high end audio and home theater items to come including times from Threshold, Theta, Rotel, Classe, Denon, Richard Gray, Kimber Kable, DVDO, Panamorph and more. Check my perfect feedback on Audiogon and on eBay as jay.d
PayPal and Audiogon Express buyers add 3%. Will charge actual shipping (and insurance, if desired) amount. Includes original double boxes and packing materials and manual.
Fun Hardware Facts (from the X3 owners manual)
The X3 has a power transformer, rated at 1000 watts, continuous duty. Under actual
conditions in the amplifier the transformer will deliver about 1800 watts for short duration.
To avoid huge inrush of current during charge up, each of the transformer primary coils has its
own inrush suppressor, which keeps the inrush down to 100 amps or so.
The X3 has 4 computer grade (the old large style computer capacitor cans, not the new dinky
ones) capacitor cans at 31,000 uF and 50 volts each. These are used to create the
unregulated output stage rails at plus and minus 30 volts at 20 amps.
In the X3, additional voltage for the front end is derived from separate windings on the main
transformer. This extra front end supply lowers the distortion and noise of the system, and
allows the front end to swing the output stage rail-to-rail with losses on the order of only a volt
or so, extracting every last possible watt.
The circuit of the amplifier is completely DC coupled, with no capacitors in the signal path.
There are also no slew rate limiting capacitors in the circuit.
All the transistors in the product are power Mosfets, actually Hexfets from International
Rectifier and Harris. These are hyper-matched parts, with gate voltages matched to 0.5% and
all devices taken from the same lot codes (made on the same wafer). The speed and noise
critical gain devices in the front end, (that is to say the actual balanced pair of transistors) are
ultra low noise and distortion matched JFETs having a low (.02 S) transconductance figure.
The JFETs are made on the same substrate for prefect matching.
The X3 has 40 output Mosfet power transistors in TO-3 plastic packages, again matched to
0.5% and drawn from the same lot codes for each type. The output stages can sustain
transients of about 1,000 watts per channel, but are not allowed to dissipate more than half
that, even into a dead short.