Parasound A 51 - Manuals

CONNECTING YOUR SPEAKERS TO THE A 51 Speaker Terminals The A 51 speaker terminals accept speaker wires with banana plugs or bare ends. Refer to Bare WireSpeaker Termination in the Technically Speaking section for information about bare wire termination. What You’ll Need: • Five lengths of AWG 16 or ...

MANUAL AND AUTOMATIC TURN ON-OFF OPTIONS You can manually turn the A 51 on and off with its front panel On-Off button. It can also be triggeredto turn on and off automatically when your preamplifier, surround controller, or system controller isturned on and off. Manual On-Off from the Front Panel If...

CONNECTING AN EXTERNAL DC SOURCE FOR AUTOMATIC TURN ON-OFF To automatically turn on and off the A 51 with an external DC voltage, choose the DC Triggeringoption by moving the Auto Turn On switch on the rear panel to its lower 12 V position. What You’ll Need: • A cable with a 2.5 mm sub-mini plug on ...

UNDERSTANDING THE INDICATORS ON THE A 51 a AC Present Indication When the A 51 is plugged into a live AC outlet, a soft blue halo glows behind its On-Offbutton and its red “P” Badge glows faintly. These indicate that the unit is plugged into a liveAC outlet, even when it is turned off. b On, Off and...

CONNECTING THE A 51 AC POWER CORD AC Power Connections We recommend that you plug your A 51 into the same AC wall outlet or power strip that pow-ers your other audio components, especially the preamplifier or system controller. Having all the audio components on the same power circuit helps prevent ...

MAINTAINING YOUR A 51 Your Parasound A 51 power amplifier requires no periodic maintenance and has no user-serviceable parts inside. To avoid the risk of electric shock, do not remove its top cover. The amplifier’s exterior can easily be cleaned with a soft cloth pre-moistened only with a few drops ...

TROUBLESHOOTING GUIDE 11 No power Auto turn on doesn’tfunction with a triggervoltage Auto turn on doesn’tfunction with an audioinput signal A 51 will not turn off whenaudio signal is removed Power on, but no sound On-Off button glows redand channel indicator(s)off Distorted sound Hum and / or buzzth...

SERVICING YOUR A 51 If All Else Fails –Call Us for Help Call your Parasound dealer or Parasound’s Technical Service Department toll free at 1-866-770-TECH (8324). We can often solve the problem with simple diagnostic tests you can per- form yourself. If we determine that your A 51 will need further ...

TECHNICALLY SPEAKING 13 Audio Trigger Sensitivity Adjustment The Audio Sensitivity Control sets the threshold of theaudio trigger signal. You can adjust this level from amaximum sensitivity of 50 mV (fully counterclockwise)to a minimum sensitivity of 250 mV (fully clockwise). If you set this control...

TECHNICALLY SPEAKING continued 14 hum (or 50 Hz hum in regions with 50 Hz AC). Theharmonics of these frequencies (120 Hz, 240 Hz, 480Hz or 100 Hz, 200 Hz, 400 Hz) may add buzz in addi-tion to the hum. The ideal of zero voltage ground for all the compo-nents in a system is practically impossible, bec...

PARASOUND A 51 DESIGN OVERVIEW 15 Circuit Designed by John Curl Parasound design consultant John Curl has been alegend among audiophiles and electronic engineersfor decades. He pioneered measurements to corre-late musical accuracy with the materials used in parts,worked with world-class touring comp...

PARASOUND A 51 DESIGN OVERVIEW continued 16 The Driver Stage The driver stage provides critical amplification forwhich we employ a complementary matched pair ofMOSFETs selected for their tube-like sonic qualities.MOSFETs tend to generate less odd-order harmonicdistortion than bipolar transistors. Th...

PARASOUND A 51 SPECIFICATIONS Power Output - All Channels Driven 250 watts RMS x 5, continuous, 20 Hz - 20 kHz, 8 Ω 400 watts RMS x 5, continuous, 20 Hz - 20 kHz, 4 Ω Current Capacity 60 amperes peak per channel Slew Rate > 130 volts per microsecond Frequency Response 5 Hz - 100 kHz, +0/-3 dB at ...