pass TM XA60 Owner’s Manual May 18, 2006 Manual XA60 Owner’s 1
Introduction 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™ XA60 monoblock amplifier is no exception. The XA60’s sleek industrial design is a stunning understatement of artistic form integrated with state of the art function.
(very loud) average acoustic signal in a 100 cubic meter room, peaks will be somewhat higher. The XA60 has a massive toroidal transformer coupled to a high current DC reservoir. Recognizing that the XA60’s ability to resolve microdynamics is best experienced with clean power, the extreme low-level resolution of the XA-series benefits from a specially designed power supply that significantly reduces and rejects power line borne noise.
We have provided a standard IEC power cord that fits into the standard 15 amp IEC receptacle at the rear of the amplifier chassis. Two XA60’s may be run on a single 15-amp circuit in conjunction with other audio components. This amplifier is equipped for operation with an earth ground provided by the users AC outlet. Never defeat this ground connection.
On the front panel, the “Standby” LED indicator should be glowing blue, indicating that AC power is available and the capacitor banks are charged. The “Power” LED should not be on. If the “Power” LED is on, don’t get excited, just use the front panel stand-by switch to go to stand-by mode, with the “Standby” LED on and the “Power “ LED off. OK, so the amplifier is sitting there in stand-by mode with just the single blue LED lit. No speaker connected yet. You can go ahead and connect the source and speakers.
XLR input connector showing proper placement of jumper pin for use with single-ended (RCA) input. Note: On X150.5 XLRs are upside down. Now that the source component is connected, make sure there is no signal coming from it, probably by turning the volume all the way down. You are ready to play music With the speakers connected, make sure the power cord is attached and plugged into mains power; toggle the front panel switch to activate the amplifier. The “Power” LED will come on.
a big deal. You should be able to put your hands on the heat sinks without discomfort for 10 seconds or so. More things to know The amplifier has a thermal cutout that will disconnect AC power if the temperature exceeds 75 degrees Centigrade. This thermal cutout should never occur in real life. You may remotely operate the stand-by mode by applying 12 volts DC to the single pair of 5 way connectors on the rear of the amplifier.
We have found that about 90 per cent of bad sounding cables are really bad sounding connections, and we recommend that attention be paid to cleanliness of electrical contact surfaces and proper connector fit. Speaker cables should be firmly tightened down at the speaker output terminals, but not with a wrench. Output terminals will not withstand the levels of torque that may be easily applied by wrench. Hand tightening without excessive force is plenty.
XA60 Specifications All figures obtained after 1 hour warm-up, with regulated 120 VAC power line. See manual notes about AC power line regulation. Gain Freq. Response Power Output Damping factor Slew rate Output Noise Balanced CMRR DC offset Power Consumption Temperature 26 dB -3 dB at 1.5 Hz, -3 dB at 100 kHz 60 watts max @ 1% THD, 1 kHz, 8 ohms plus, minus approx. 40 volts plus, minus approx.
Warranty Information Please check with the factory-authorized distributor in the country you are purchasing this product for specific warranty information. All Pass Laboratories products purchased from an authorized Pass Laboratories dealer in North America are covered by a transferable, limited 3-year warranty. This warrantee includes all parts and labor charges incurred at the repair facility in addition to return shipping to the domestic customer, exclusive of subsequent damages.
For your protection please read the following: Water and moisture: Electrical devices should not be used near water ( as per example, near a bathtub, washbasin, kitchen sink, laundry tub, wet basement or swimming pool ). Care should be taken such that objects do not have the opportunity to fall, and that liquid is never spilled onto or into the device enclosure through openings.
XA White Paper: Like Peanut Butter and Chocolate © Nelson Pass Sometimes two designs complement each other so well that you are surprised when you learn they weren’t invented together. So it is with the X Supersymmetery™ amplifier and the Aleph single-ended Class A output circuit. The Supersymmetery™ “X” amplifier repeatedly demonstrates the possibilities for very high power, dramatic dynamic contrast, and effortless control by a simple circuit utilizing absolutely minimal feedback.
they vanish at the output, typically by a factor of 10 or so for matched single-ended Class A circuits. Supersymmetry™ extends this concept by using feedback only to make the distortion and noise more identical on each half of a balanced circuit, not to eliminate it as such. This gives as much as a 100:1 reduction in unwanted distortion and noise without requiring the equivalent amount of negative feedback.
The amplifier has only the two stages, an input stage of a balanced pair of input devices, and the output stage, a balanced pair of single-ended Class A power Mosfets. Like the Aleph™, you can trace a path from input to output through only two gain devices. Like the X amps, feedback is used only to set the gain and correct for dissimilarities between the two matched output stages. There are no adjustments. There are no frequency compensation capacitors.
