POWERLIGHT 2A User Manual Manuel de l’utilisateur Bedienhandbuch Manual del Usario PL2A Audio Power Amplifiers with Analog Signal Processing *TD-000089-00* TD-000089-00 Rev.
EXPLANATION OF GRAPHICAL SYMBOLS The lightning flash with arrowhead symbol within an equilateral triangle is intended to alert the user to the presence of uninsulated “dangerous” voltage within the product’s enclosure that may be of sufficient magnitude to constitute a risk of electric shock to humans. The exclamation point within an equilateral triangle is intended to alert the user to the presence of important operating and maintenance (servicing) instructions in the literature accompanying the product.
TABLE OF CONTENTS Explanation of Graphical Symbols.......................................................2 CONNECTIONS: Inputs................................................................................21 Outputs............................................................................22 FCC Interference Statement....................................................................2 SECURITY PANEL USE & INSTALLATION...................................................
INTRODUCTION: PL2A OVERVIEW Thank you for the purchase of your new POWERLIGHT 2A amplifier. To get the most out of your amplifier, review this manual carefully. The installation and operation sections provide proper connection and operation guidelines. The POWERLIGHT 2A expands upon the features of the POWERLIGHT 2. The flexibility, user-friendliness and reliability of this amplifier will make it a valuable part of your system for years to come. The POWERLIGHT 2A was designed to fit your system.
INTRODUCTION: PL2A OVERVIEW REAR PANEL 1. DataPort 2. Terminal block inputs 3. Configuration switches 4. XLR inputs 5. Speakon outputs 6. Binding post outputs 7. Cooling air inlet vents 8. Serial number label 9. IEC connector for AC power cord 9a. Power cord retaining clip (install on item 8) SIDE PANEL 1. Low pass delay network SIP* socket (J5) 2. Crossover frequency network SIP socket (J4) 3. Subaudio filter push-button switches (1 per channel) 4. Subaudio filter “on” indicator LEDs (1 per channel) 5.
FEATURES & SETUP- REAR PANEL SWITCHES: INPUT CONFIGURATION INPUT CONFIGURATION- This switch selects between STEREO or PARALLEL input configuration. The indicator LED’s above the switch confirm the switch setting. STEREO: Each input is sent to its respective channel. Each channel has independent subaudio filtering, clip limiting, gain control, and outputs. In STEREO mode, a full-frequency signal may be presented to each channel.
FEATURES & SETUP- REAR PANEL SWITCHES: MODE MODE- This switch selects between BI-AMP, 2 CH, or BRIDGE modes of operation. The indicator LED’s above the switch confirm the selection. BI-AMP: This puts the amplifier into a “crossover” mode. CH 1 receives the low frequencies and CH 2 is receives the high frequencies. The crossover is a 4th order Linkwitz-Riley. The crossover frequency and lowfrequency alignment delay are “programmed” with SIP (single in-line package) resistor networks .
FEATURES & SETUP- REAR PANEL SWITCHES: DATAPORT INPUT SIGNAL DATAPORT INPUT SIGNAL- This switch selects the regular inputs or the DataPort inputs, and allows the DataPort to enter before or after the analog processing. WARNING: There is no DataPort “flag” for this setting, so the appropriate setting must be confirmed manually. OFF: If the DATAPORT CONNECTION is not being used, set to the OFF position.
FEATURES & SETUP- REAR PANEL SWITCHES: GAIN-SENSITIVITY SELECT GAIN-SENSITIVITY SELECT- This switch selects the gain structure of the amplifier. Each channel runs through a gain buffer which allows all models to have either a uniform 1.2 Vrms input sensitivity or a uniform 26 or 32 dB of voltage gain (all measured with the GAIN controls at maximum). The internal signal leaving this stage is approximately +4 dB, leaving about 16 dB of headroom for the rest of the signal processing.
FEATURES & SETUP- SIDE PANEL SWITCHES: SUBAUDIO FILTER and SUBAUDIO FREQUENCY The side panel cover plate must be removed to access the side panel switches. CH1 SUBAUDIO FILTER, CH2 SUBAUDIO FILTER- These push-button switches are used to turn on or off the SUBAUDIO FILTER for each channel. Press the switch in for ON; the green LED illuminates when the filter is ON. Push in and allow the switch to release for OFF; the green LED extinguishes when the filter is OFF.
FEATURES & SETUP- SIDE PANEL SWITCHES: LO FREQ DELAY and HF ATTEN LO FREQ DELAY- This switch is active only when the amplifier is in BI-AMP mode. This switch controls an additional analog delay which adds to the inherent delay of the low frequency filter. The amount of delay is determined by the SIP programming network installed in the DELAY NETWORK socket (J5). DELAY OFF disables the delay. ENABLE LO FREQ DELAY activates the delay. Refer to the SIP network value selection chart for more information.
FEATURES & SETUP- SIDE PANEL SWITCHES: HORN BOOST HORN BOOST- These switches are only active when the amplifier is in BI-AMP mode. These switches work in combination to control the amount of high-frequency horn boost. The horn boost is adjustable from 0 to 14dB in 2dB steps as measured at 20 kHz. Add the values of the selected switches for the total boost.
FEATURES & SETUP- SIDE PANEL SWITCHES: POWER LIMITER POWER LIMITER: Each channel has its own limiter with independently adjustable threshold and time constants. A ten-section switch for each channel controls the limiter settings. LIMITER ACTIVITY LED’s: Just below the CH 1 and CH 2 labels you will note a clear circle which has a yellow LED behind it. Each LED illuminates only when its limiter is reducing gain.
FEATURES & SETUP- SIDE PANEL SWITCHES: POWER LIMITER (continued from previous page) FAST- Set both POWER LIMITER SPEED switches to FAST. This setting produces 20 milliseconds (0.020 seconds) of release time. The AVG mode will produce 8 milliseconds of attack time, and PEAK mode will produce less than 1 millisecond of attack time. This setting will have low distortion down to about 1 kHz.
FEATURES & SETUP- SIDE PANEL SWITCHES: CLIP LIMITER POWER LIMITER TRACKING- continued The high frequency driver requires a lower power threshold and fast limiting response. Try the FAST setting and the PEAK mode. Short peaks will be limited aggressively, but signals will return to normal almost instantly. This response (fast with low threshold) would have too much “ducking” and low frequency distortion for use with full range material.
FEATURES & SETUP- SIDE PANEL: CROSSOVER & DELAY NETWORK SELECTION & INSTALLATION SIP RESISTOR NETWORK INSTALLATION GUIDELINES AND SELECTION INFORMATION DECODING SIP NETWORK RESISTANCE VALUES (see note below decoding chart) Your PL2A amplifier is shipped configured to order with SIP networks installed.
FEATURES & SETUP- SIDE PANEL: CROSSOVER & DELAY NETWORK SELECTION & INSTALLATION Turn the power to the amplifier off before removing or installing SIPs! The SIPs may be installed “either way”. The SIPs are symmetrical and thus perform identically no matter which end points to the left or right. This completely eliminates “polarity” errors that might otherwise arise. The side cover plate must be removed to access the SIP sockets. Be sure to reinstall the side cover plate after installing the SIPs.
FEATURES & SETUP: DATAPORT, FRONT PANEL LED INDICATORS, GAIN CONTROLS DATAPORT CONNECTOR The PL2A amplifier features a QSC DataPort connector which connects to accessory products to enhance your amplifier application. The CM16a Amplifier Network Monitor can remotely control and monitor your PL2A amplifier. The DSP-3 digital signal processor can mount directly to the rear of your PL2A amplifier, adding an incredible amount of processing power in a small, powerful module at a very competitive price.
INSTALLATION: RACK MOUNTING AND MOUNTING DIMENSIONS Before installing into equipment rack: ensure that all side-access DIP switches and crossover SIPs are setup as desired. They will be impossible (or extremely difficult) to change after the amplifier is installed in the rack. The side cover plate should be installed to keep dust and foreign material out of the chassis. Securing the Front Ears to the Rack Rails Use four screws and washers when mounting the PL2A amplifier to the front rails.
INSTALLATION: FAN COOLING & AC MAINS FAN COOLING The fan varies speed automatically to maintain safe internal temperatures and minimize noise. Keep the front and rear vents clear to allow full air flow. Hot air exhausts out the front of the amp so it does not heat the interior of the rack. Make sure that plenty of cool air can enter the rack, especially if there are other units which exhaust hot air into it. Keep the front and rear vents clear to allow full air flow.
CONNECTIONS: INPUTS INPUTS Each channel has active balanced "Euro-style" terminal block and XLR jacks wired in parallel. The input impedance is 12 kOhm balanced or 6 kOhm unbalanced. Each channel's input jacks are wired in parallel. Unused input jacks may be daisy-chained to additional amplifiers if desired. Balanced connection is recommended. Balanced signals are less prone to AC hum, but unbalanced signals can be suitable for short cable runs.
CONNECTIONS: OUTPUTS OUTPUTS: PL2A amplifiers offer a choice of output connections; Neutrik NL4MD Speakon jacks and "touch-proof" binding post outputs. SPEAKER CABLING: Always use the largest wire size and shortest length of wire practical for any given installation. Larger wire sizes and shorter lengths minimize power loss and degradation of damping factor. Do not place speaker cables next to input wiring.
CONNECTIONS: OUTPUTS Binding post outputs Three connection methods may be used to connect to the binding post output terminals: • wire inserted from the side then the retaining nut is tightened • spade terminal inserted from the side then the knurled retaining nut is tightened • banana plug inserted into the post Banana plug capability is provided on non-European models ONLY! Binding Post strip length, spade terminal size and connection methods Stereo, bi-amp, or parallel mode Modes stéreo, bi-amp ou para
SECURITY PANEL USE & INSTALLATION Right: a POWERLIGHT 2A amplifier with security panel installed A droite: le panneau avant avec plaquette protectrice installée Rechts: ein POWERLIGHT 2A-Verstärker mit Sicherheitsabdeckung Derecha: un amplificador PL2 Acon el panel de seguridad instalado SECURITY PANEL After setting the gain controls, you can install the security panel to prevent tampering and accidental misadjustment.
OPERATION GAIN CONTROLS Turn down the gain controls before applying power. The gain controls are detented 21 steps for repeatable adjustment. Surrounding the gain control knob, the attenuation level is shown in dB. The gain structure may be selected on the PL2A. On the rear panel you will find a switch labeled GAIN-SENSITIVITY SELECT; you may select from +4 dB input sensitivity, 32 dB or 26 dB of voltage gain. AC POWER SWITCH Before applying power, check all connections and turn down the gain controls.
TROUBLESHOOTING: NO SOUND Problem: NO SOUND • INDICATION: POWER INDICATOR NOT LIT • Check the AC plug. • Confirm that the AC outlet works by plugging in another device. If too many amplifiers are used on one outlet, the building's circuit breaker may trip and shut off power. • An overload in bridge mode may cause the amplifier to click off for three seconds, indicated by the half-bright POWER LED, followed by a normal restart cycle. Check the load impedance (4 ohms minimum), or reduce signal level.
TROUBLESHOOTING: DISTORTION, NO CHANNEL SEPARATION, HUM, HISS, FEEDBACK PROBLEM: DISTORTED SOUND • INDICATION: CLIP LED FLASHING • If the red CLIP indicator flashes before all three signal indicators do, the load impedance is abnormally low or shorted. Unplug each speaker one-by-one at the amplifier. If the CLIP LED goes out when you disconnect a cable, that cable or speaker is shorted. Try another cable and speaker to locate the fault.
TECHNICAL OVERVIEW: BLOCK DIAGRAM & OPERATIONAL DETAILS An impressive amount of technology is packed "under the hood" of a PL2A amplifier. Thousands of watts of power flow inches away from stateof-the-art low noise inputs. Precise circuit layout and thorough protection assure that all of this activity occurs smoothly and safely. So, what actually happens when you turn on the power switch? Soft Start Sequence. The first task is to charge the primary energy reservoir without drawing a large surge current.
TECHNICAL OVERVIEW: BLOCK DIAGRAM & OPERATIONAL DETAILS High Performance Audio. High speed power transistors convert this DC power into the full range audio output which drives the speakers. High-current design and special dual-sense output feedback corrects errors on both sides of the speaker terminals, improving damping and control of speaker motion. The power devices are directly mounted to isolated heat sinks, which form a short, wide air tunnel in front of the fan for optimum cooling.
S P E C I F I C AT I O N S PL218A PL224A PL230A PL236A OUTPUT POWER in watts FTC: 8 ohms per channel (20-20k Hz., 0.05% THD) 4 ohms per channel (20-20k Hz., 0.07% THD) 310 525 440 715 575 900 725 1100 EIA: 1 kHz 8 ohms per channel 350 475 625 800 @1% THD 4 ohms per channel 600 825 1050 1300 2 ohms per channel 900 1200 1500 1850 650 1100 1800 900 1500 2400 1200 2000 3000 1500 2400 3600 -103 dB -103 dB Bridged Mono: 16 ohms, 20–20k Hz, 0.1% THD 8 ohms, 20–20k Hz, 0.
S P E C I F I C AT I O N S PL218A PL224A PL230A PL236A INDICATORS (all models) Front: POWER: Green LED, STANDBY: POWER LED 1/2 brightness, BRIDGED: Yellow LED, PARALLEL: Orange LED, BI-AMP: Blue LED, CLIP/Protect: Red LED, 1 per channel, Level -10 dB: Orange LED, 1 per channel, Level -20 dB: Green LED, 1 per channel, SIGNAL -35dB: Green LED, 1 per channel Back: STEREO: Green LED, PARALLEL: Orange LED, BI-AMP: Blue LED, 2 CH: Green LED, BRIDGE: Yellow LED, DATAPORT PRE PROC: Blue LED, DATAPORT OFF: Gre
WARRANTY INFORMATION & HOW TO CONTACT QSC AUDIO PRODUCTS WARRANTY (USA only; other countries, see your dealer or distributor) HOW TO CONTACT QSC AUDIO PRODUCTS Mailing address / Adresse postale / Postanschrift / Dirección postal: QSC Audio Products, Inc. 1675 MacArthur Boulevard Costa Mesa, CA 92626-1468 USA Disclaimer QSC Audio Products, Inc.
SETUP SHEET FOR PL2A AMPLIFIERS Use these handy sheets to mark your switch positions for various setups. Each switch position has been “blanked” out so that you may place an “X” or a checkmark to indicate the setting of each switch for future reference. Copy these blanks so that you have several copies.
SETUP SHEET FOR PL2A AMPLIFIERS Use these handy sheets to mark your switch positions for various setups. Each switch position has been “blanked” out so that you may place an “X” or a checkmark to indicate the setting of each switch for future reference. Copy these blanks so that you have several copies.
QSC Audio Products, Inc. 1675 MacArthur Boulevard Costa Mesa, California 92626 USA “QSC” and the QSC logo are registered with the U.S. Patent and Trademark Office. ©2000, 2007 QSC Audio Products, Inc.
