REPRINTED FROM JANUARY 2008

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QSC PL380 PowerLight3 Amplifier
This analog amp offers a powerful 8,000-watt argument as to why QSC is a go-to name in live by David Rittenhouse sound reinforcement.
QSC is a name that has been around for some time now. At one point or another, potentially everyone in the industry has rated from 20 Hz to 20 kHz 0.2 dB. Maximum distortion is rated at 0.20 percent from 4 to 8 ohms, with noise rated at
thermal, RF and DC fault is also there, along with on/off muting and active inrush limiting. | IN USE I had the opportunity to use the PL380 for several months. The first thing I did after opening the box was to change out the Twist-Loc power connector to a regular 20A Edison. This way, I could use the amp in any situation that might pop up (and they did pop up more frequently than even I would have wanted). I found the PL380 very robust in the
been exposed to at least one or more of the companys products. Now that market penetration continues with the new QSC PowerLight3 series amplifiers or, as QSC puts it, the ultimate analog amplifier. | FEATURES The PowerLight3 upgrades the PowerLight2 series, adding and refining some appreciated functions. The new PL380 ($3,599) is QSCs flagship model, with an output of 8,000 watts (two channels driven at 2 ohms at 4,000 watts per channel). The PL380 is rated as a Class D switching power supply amp. This amp features QSCs reactive back EMF, which recycles the unused energy back to the power supply to produce an AC efficiency of up to 85 percent, keeping AC power demand to a minimum. The PL380s frequency response is
-104 dB. Input sensitivity is adjustable from three settings: 26 dB (5.27V), 32 dB (2.67V), and 1.2V (39.1dB) with input impedance set at >10k ohms. The Damping factor at 8 ohms is rated at 200. All of the standard input and output connectors are on the amp: XLR inputs with Neutrik and 5-way binding post outputs. The front panel of the PL380 is common with most other QSC amps, with attenuation knobs from each channel (the standard LED Christmas Tree of signal). The PL380 sits in only two rack spaces, and weighs in at a respectable 24 pounds. The PL380 also supports remote control through QSCs QSControl BASIS networked audio platform and the DataPort at the rear of the amp. The PL30 is shipped with an 18A/30A Twist-Loc power cable to a Neutrik Power-Con at the amp. All of the common amplifier and load/power protection of short circuit, open circuit,
APPLICATIONS Live reinforcement, permanent installs KEY FEATURES 8,000 watts (two channels driven at 2 ohms at 4,000 watts per channel); Class D; QSC reactive Back EMF; XLR inputs with Neutrik and 5-way binding post outputs PRICE $3,599 CONTACT QSC Audio | 800-854-4079 www.qscaudio.com
Copyright 2008 JRS Publishing (USA), Inc. Reprinted with permission.
fact that it was lightweight, yet very powerful. I was able to run it as an extra sub amp, or as an extra amp for additional front fills on multiple shows. I loved the fact that QSC utilized the back panel connections to work with whatever could be thrown at them. Having both binding post and Neutrik outputs and parallel XLR inputs made things easier when adding it
subs per side. The PL380 held up, and even sounded beefier and punchier than what I already had in my racks. With 2,500 watts per channel at 4 ohms, the PL380 exceeded my expectations. It was also
its versatility. Since then, I have used the PL380 on almost every show as my total utilitarian amp Id just grab it and go! At every show, the PL380 outperformed almost everything else I owned. The sonic

PRODUCTPOINTS

Powerful Lightweight Great utility amp
No DSP without additional gear
Overall, a powerful improvement over the older series.
in to existing systems, like I did without the need of additional, sometimes flimsy, adapters. The PL380 sounded great, clean, and quiet (when it needed to be). I used this amp on a large, last-minute Latin concert where I had to add two more EAW SB850
good to find out that I could drive this amp hard for hours without it having any problems. The next time out was on a simple corporate talking heads gig. I needed to add some front fills in, as the hotel ballroom was wider than I was expected. I knew I did not need an amp as powerful as the PL380, but it was what I had left in the shop. Needless to say, the PL380 sounded great and powered Community Veris 6s just fine. I even used it to power some EAW JF100s for a lobby plasma screen presentation at a corporate ballroom show, and sent it out once with a DJ and some full-range speakers just to see what it would do. It responded great. Yes, it was some serious overkill, but it proved
quality was fantastic, from subs to high end to full range cabinets, with more power than you would need for anything in almost every arsenal. It ran cool and quiet and never thermaled, never shut down, and never left me hanging. | SUMMARY Today, there are more amplifier choices flooding you than you can wrap your head around or even have time to audition. QSCs PL380, however, stands out as a simply great product at a great price, offering the Swiss Army Knife of amps. David Rittenhouse is the senior sales executive and A1 engineer at Event EQ in Baltimore, MD, and a regular contributor to PAR.

Reprinted from Pro Audio Review

BENCH TEST

QSC PL380 Power Amplifier
BENCH MEASUREMENT DATA Maximum Power (1 kHz, 1% THD) (See Notes) Stereo 8-ohm loads Stereo 4-ohm loads Stereo 2-ohm loads Bridged 4 ohm load Dynamic Output Power Stereo 8 ohm loads Stereo 4 ohm loads Stereo 2 ohm loads Bridged 4 ohm loads Dynamic Headroom Stereo 8 ohm loads Stereo 4 ohm loads Stereo 4 ohm loads 1.1 dB 1.9 dB 3.0 dB 1.8 kW, 32.6 dBW 3.6 kW, 35.6 dBW 6.0 kW, 37.8 dBW 12.0 kW, 40.8 dBW 1.4 kW, 31.5 dBW 2.3 kW, 33.6 dBW 3.0 kW, 34.8 dBW 6.0 kW, 37.8 dBW Sensitivity for rated output, 1.5 kW, 8-ohm 26 dB 5.17 V, 16.5 dBu 32 dB 3.62 V, 13.4 dBu 1.2V 1.12 V, 3.2 dBu Output noise, 32 dB gain setting, Ch1/Ch2 (essentially gain setting Independent) Wideband 110/200 mV | -28.2/-23.0 dBW A - Wtd 816/852 uV | -70.8/-70.4 dBW Signal to noise ratio re: 1.5 kW into 8 ohm, 32 dB gain setting A - Wtd 102.4 dB Fig. 2: Frequency response of the Low and High cut filters. Red = Flat, Magenta = 30 Hz low cut, Blue = 50 Hz low cut low-cut filter positions of 30 & 50 Hz. THD+N for a 1 kHz test signal and for 8, 4, and 2 ohm loading in the stereo mode are shown in Fig. 3. Distortion is reasonably low and noise dominated up to about 10W and then begins to rise with 8-ohm loading. The relatively controlled. This is shown in Fig. 1 for frequencies greater than 10 kHz and loads of open circuit, 8, & 4 ohm. Low frequency response was very extended. This is plotted in Fig. 2 along with the response of the two
Channel Separation, 20 Hz - 20 kHz Ch 1 > 2 , Ch 2 > 1 Power draw @ idle > 50 dB 153 W, 0.58 PF, 2.2A
THD+N at near rated power (20 Hz - 20 kHz) Stereo 8 ohm loads <0.02% @ 1.0 kW, 20 Hz 2 kHz < 0.6% @ 1.0 kW, 20 kHz Stereo 4 ohm loads <0.05% @ 1.5 kW, 20 Hz 2 kHz < 1.0% @ 1.5 kW, 20 kHz THD+N at 10W output (20 Hz - 20 kHz) Stereo 8 ohm loads Stereo 4 ohm loads Damping Factor, 50 Hz re 8 ohm Output Impedance magnitude at: 50Hz 1 kHz 5 kHz 10 kHz 20 kHz Input Impedance 38.8 milliohm 57.4 milliohm 196.7 milliohm 393.9 milliohm 867.9 milliohm 14.7 kilohm < 0.08% < 0.1% 206

Notes: Unless otherwise noted or implied, all measurements are made with 8-ohm loads from the balanced XLR inputs, stereo mode with the volume set to maximum and gain set for 32 dB. Both channels driven for all distortion and power measurements. Measurements made on one channel are made on channel two. Power output measurements were limited by the regulation and resultant voltage drop under power of my AC supply. BENCH MEASUREMENT COMMENTARY The QSC PL380 is one brute of an amplifier! This most powerful of the PL series utilizes both a switchmode power supply and a Class D switching power amplifier circuit. This one definitely exceeded the regulation capacity of my external AC supply fed from a sub-panel outside of my lab. My load resistors could take it for the relatively short time of the distortion vs. power tests. Class D amplifiers in general have an out of band high frequency response that is a function of load impedance value due to their necessary LC output filters. The PL380 has this
Fig. 3: THD+N of 1 kHz signal vs. power output for 8, 4, & 2 ohm loading, bottom to top at 100W lower impedance loads cause more distortion above the 10W level which is not surprising. As mentioned above, my AC supply couldnt hold the voltage up enough under this VERY high amperage load to make the rated power at the lower loads. But still, 3 kW per channel aint bad! No doubt the amp would meet its ratings with a maintained 120V AC line input. Plotting THD+N as a function of frequency and power for 4 ohm loading, distortion is low up to about 2 kHz, where it begins to rise and gets to pretty high values above 10 kHz at the 1.5 kW and higher levels. The 1 & 10W levels are noise dominated. The damping factor vs. frequency shows an unusual, in my experience, increase in DF below about 50 Hz. In terms of Channel separation, unusual is the more or less flat nature of the separation vs. frequency. Much more usual is a characteristic that rises with frequency due to capacitive coupling in the signal circuitry. Bascom King
Frequency Response, 4-ohm load 20 Hz - 20 kHz +/- 0.0 dB - 3 dB at < 10 Hz, 58 kHz Voltage Gain, 8-ohm load, vs. gain setting 26 dB 21.2X, 26.5 dB 32 dB 41.8X, 32.4 dB 1.2V 92.1X, 39.3 dB Sensitivity for 0 dBW, 8-ohm load 26 dB 32 dB 1.2V 133 mv, -15.3 dBu 67.7 mv, -21.2 dBu 30.7 mv, -28.0 dBu
Fig. 1: Frequency response at the 1W/8 ohm level as a function

PowerLight 3 Series

The PowerLight3 Series is designed for the most demanding live audio users, whether in touring rigs or fixed installations. The most requested features of the PowerLight 2 series have been upgraded to deliver the ultimate analog amplifier, while the QSC DataPort ensures full compatibility with advanced digital processing and QSControl.net. Three models range in power from 1250 watts to 4000 watts per channel at two ohms, all in two-rack space chassis that are only 15.6" (40 cm) deep and 22 lb (10 kg). In addition to higher power, the PowerLight 3 Series offers higher input voltage, selectable sensitivity, and easily adjusted rear panel switches with color coded LED indicators. For those users who simply want a high performance amplifier to go with their existing processor or console, the PowerLight 3 Series is an ideal choice, offering high power, excellent value, and zero signal latency. When complete integration of amplifier control, monitoring and DSP is desired, the PowerLight 3 Series is fully compatible with the QSControl.net BASIS networked audio platform, with its comprehensive drag and drop DSP functionality. Simpler DSP requirements can be met with the DSP-4 processing module. The flagship of the PowerLight 3 Series is the new 8000 watt PL380. This highly refined, all-switchmode amplifier incorporates nearly 40 years of QSC engineering experience, resetting expectations for Class D audio quality. The PL380 combines a pair of 4000 watt Class D amplifier channels with the well proven PowerLight supply, to deliver more than twice as much audio power as previous 2 rack unit PowerLight amplifiers. Reactive back EMF from the speaker is recycled to the power supply, and unmatched plug-to-plug efficiency of 85% keeps AC power needs to a minimum, while delivering more energy to the speaker. Years of patient development have resulted in outstanding 20 Hz 20 kHz audio performance, plus complete protection from normal hazards of the trade. Even simple features such as dependably silent, surge-free on-off switching indicate the special care taken to keep things safely under control. The most pronounced sonic signature of the PL380 is one of immense headroom, sailing through even the most difficult loads with no signs of stress or change of tonality. For lower power applications, the PL325 and PL340 offer the same feature set, matched to upgraded versions of QSCs most advanced linear amplifier platform. Recent advances in power supply capacitors further improve power and low-impedance performance, while continuing to offer the best available audio performance. As a result, designers have the choice of running a single type of amplifier throughout their rig, or matching amplifier performance to specific transducer types. In keeping with normal QSC design standards, back-to-front airflow provides up to twice as much long-term average power as most competitors, without dumping hot air into the rack. All PowerLight 3 models are built in the same chassis size, with common back panel layouts to facilitate easy racking and hookup. PowerLight 3 Power Amplifiers - Watts at Clipping Model 8 PL325 PL340 PL380
EIA 1 kHz 1% THD *Burst mode testing required due to AC service current limitations
Professional Power Amplifiers

PL325 | PL340 | PL380

Features
PowerLight switchmode power supply for highest efficiency and improved audio performance Flow-thru air path and solid aluminum heat sinks for maximum cooling DataPort supports remote computer control and/or external DSP-4 modules Detented gain controls with 1dB steps for precise calibration Removable knobs with lock-out security plate to prevent unauthorized tampering User defeatable clip limiters and selectable low-frequency filter per channel (3Hz, 30Hz, or 50Hz) Three selectable input gains (26 dB, 32 dB, or 1.2V) Front and rear panel LEDs indicate status of switch settings at a glance Parallel Dataport, XLR/M and XLR/F connectors for simple loop-through connectivity Neutrik Speakon and Touch Proof binding post outputs Neutrik Powercon power cable remains secure on the road 3-year warranty, plus optional 3-year extended service contract

PL340 and PL325

2000 4000*
Watts per channel 1250 2500
Linear Class H output circuit doubles standard Class B efficiency to reduce AC current consumption and cooling requirements
Class D output circuit re-doubles the output power with even lower losses and minimal increase in average AC power, dramatically reducing power distribution demands compared to older high power amplifiers
PL325 Stereo Mode (both channels driven) 8 / EIA 1 kHz / 1% THD 4 / EIA 1 kHz / 1% THD 2 / EIA 1 kHz / 1% THD Bridge-Mono Mode 8 / EIA 1 kHz / 1% THD 4 / EIA 1 kHz / 1% THD Typical Distortion (20 Hz 3 kHz, 3dB below clip, or 20 Hz 5 kHz, 10dB below clip, or 20 Hz 20 kHz, 20dB below clip) 2 Maximum Distortion (20 Hz 20 kHz, 1 dB below rated power) Frequency Response (8) Noise (20 Hz 20 kHz, 32 dB Gain) Dynamic Headroom (4) Damping Factor (8) Output Circuitry Input Sensitivity (26 dB Setting) (32 dB Setting) Input Gain (1.2V Setting) Input Impedance Maximum Input Level (1.2V Setting) (32 dB Setting) (26 dB Setting) Controls and LEDs - Front Panel Controls and LEDs - Rear Panel Input Connectors Output Connectors Amplifier and Load Protection AC Power**/Cordset 120V 50/60 Hz 230V 50 Hz Chassis Power Connector (All Voltages) Dimensions (HWD) Weight - Net/Shipping Agency Approvals 500 W 850 W 1250 W 1700 W 2500 W PL340 PLW 1250 W 2000 W 2600 W 4000 W 1500 W 2500 W 4000 W* 5000 W 8000 W*

Specifications

0.002 0.01% 0.005 0.01% 0.02%
0.01 0.03% 0.03 0.06% 0.10%
0.05% 20 Hz 20 kHz, +/-0.2 dB -106 dB 2 dB 500 2-tier Class H 3.28V 1.60V 34.5 dB >10k, balanced or unbalanced 11V (+23 dB) 14.6V (+25.5 dB) 25V (+30 dB)
0.05% 20 Hz 20 kHz, +/-0.2 dB -105 dB 2 dB 500 2-tier Class H 3.92V 1.96V 36.4 dB >10k, balanced or unbalanced 11V (+23 dB) 18V (+27.4 dB) 25V (+30 dB)
0.20% 20 Hz 20 kHz, +/-0.2 dB -104 dB 2 dB 200 Class D 5.27V 2.67V 39.1 dB >10k, balanced or unbalanced 10V (+22 dB) 22V (+29 dB) 25V (+30 dB)
Common: AC Power Switch, Power (Blue), Br Mono (Yellow), Par (Orange) Each Channel: Signal -35 dB, -20 dB (Green), -10 dB (Orange), Clip/Prot (Red) Gain Control, 21 detents, 1 dB steps Common: Input Mode: Parallel (Orange), Stereo (Green), Br Mono (Yellow) Sensitivity: 26dB (Orange), 32dB (Green), 1.2V (Yellow) Each Channel: LF Filter: Off, 30 Hz (Yellow), 50 Hz (Orange) Clip Limit: Off, On (Yellow) Common: HD-15 DataPort (inputs wired in parallel with XLR) Each Channel: Male XLR, Female XLR, 3-pin terminal block connector Each Channel: 5-way Binding Posts, Neutrik Speakon, (Ch 1 wired to both channels) Short circuit, open circuit, thermal, RF protection. On/off muting, DC fault shutdown, active inrush limiting 8.5A/NEMA-15 7.5A/CEE 7/7 16A 20A PowerCon 22 lb (10 kg) / 31.5 lb (14.3 kg) 12A/NEMA-15 7A/CEE 7/7 16A 20A PowerCon 22 lb (10 kg) / 31.5 lb (14.3 kg) 18A/NEMA L5-30P 11A/CEE 7/7 16A 32A PowerCon 24 lb (11 kg) / 33.5 lb (15.2 kg)
Height: 3.5" (8.9 cm) 2 RU / Width: 19" (48.3 cm) / Depth: 15.63" (39.7 cm) from front mounting rails UL, CE, RoHS/WEEE compliant, FCC Class B (conducted and radiated emissions)
* Burst mode testing required due to AC service current limitations ** Representative of current draw with typical music program material with occasional clipping
All specifications are subject to change without notice.
QSC, the QSC logo, PowerLight, QSControl.net and BASIS are registered trademarks of QSC Audio Products, LLC in the U.S. Patent and Trademark office and other countries. Speakon and Powercon are trademarks of Neutrik. All other trademarks are the property of their respective owners. US Pat. 5767744. Other patents may apply or be pending.
1675 MacArthur Boulevard Costa Mesa, CA 92626 Ph: 800/854-4079 or 714/957-7100 Fax: 714/754-6174
PowerLight 3 Spec Sheet 10/03/08

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