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Mackie CFX-20 Mixer w/ Built-In Effects
Mackie CFX-20 Mixer w/ Built-In Effects

Sales - I-215PSB ISIS Series Active Subwoofer System Without Top Box Electronics

Manufactured By:
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CSL Sales Note

This subwoofer is identical to the 215PCM, except it does not contain the top box electronics (amplifier and DSP unit) for the satellite speakers.

Product Description

ISIS Series /215PCM /215PSB /215SB Self-Powered System Core Module

The 215PCM is a self-contained active subwoofer system with dual 15-inch drivers. It provides power amplification not only for itself, but also two channels for driving stereo full-range or mono bi-amp "top box" speakers as well. Thus, it serves as a core module for portable live sound reinforcement systems and is ideal for corporate/industrial events. The 215PCM can supply extreme SPL within the recommended bandpass of 35-150 Hz (-3 dB). The 215SB is a passive subwoofer system with no backpack electronics. The 215PSB is a powered subwoofer, but without the "top-box" electronics.

The power and processing electronics of the 215PCM are contained in a backpack mounted on the rear of the subwoofer enclosure. Powering the 215PCM and 215PSB is an integral 3000-watt amplifier (equivalent to a bridged-mono PL 230) for the subwoofer itself. For the 215PCM, the backpack also contains a two-channel amplifier equivalent to a PL 236 (725 W @ 8 ohms; 1100 W @ 4 ohms; 1850 W @ 2 ohms) for the top boxes.

The subwoofer amp and the top-box amp each have the processing equivalent of a DSP-3. Both processing units have eight user-configurable and -selectable presets (using a personal computer and QSC’s Signal Manager software).

The cabinet of the 215 enclosure is constructed of Composilite™ carbon fiber composite material, which is extremely stiff and strong. The high rigidity of the cabinet walls raises the enclosure’s natural resonances to frequencies higher than the subwoofer’s operating range, so the cabinet performs as an ideal enclosure.

A bonus of the Composilite material is its very light weight, which enhances the cabinet’s portability. Strategically placed wheels and handles on the backpack provide easy single-person mobility.

Of Lightweight Boxes, Diametric Drive, And Newton’s Third Law Of Motion

The cabinets of all 215 enclosures are constructed of Composilite™ carbon fiber and composite materials, which is extremely stiff and strong. The high rigidity of the cabinet walls raises the enclosure’s natural resonances to frequencies higher than the subwoofer’s operating range, so the cabinet acts more like an ideal enclosure.

Composilite construction significantly reduces the weight of the subwoofer, making it easier and more cost-effective to transport. The system is designed for single-person portability; by leaning the cabinet back onto its two casters and grasping the handles at the upper rear corners, one person can easily roll it across a floor or other flat surface.

Sir Isaac Newton’s third law of motion states that to every action, there is an equal and opposite reaction. This reality presents a challenge for subwoofer cabinets. Subwoofer cones have significantly higher mass than those of other types of speaker driver, and the low frequencies theyreproduce require large displacements. Thus, the forces that move the cone forward and backward also make the enclosure move the opposite way in reaction. The enclosure’s vibrations tend to turn its walls into radiating surfaces and its supporting feet into walking appendages. The inertia of a heavy box naturally resists opposing motion. However, a lightweight enclosure like the 215’s has relatively little inertia, so instead it uses two identical and diametrically opposed 15-inch drivers to ensure inertial stability. The drivers face each other and move equally but in opposite directions. The net effect is that the driver forces counterbalance, minimizing vibration in the cabinet.


  • Highest output to size ratio available
  • 3000W powerplant for sub (215PCM and 215PSB) – 3600W, 2 channel powerplant for accompanying top enclosures (215PCM)
  • User configurable DSP for both sub and top enclosures with eight storable presets for each (215PCM and 215PSB)
  • Removable backpack houses processing and amplification for system (215PCM and 215PSB)
  • Dual High power 15" drivers rated at 1400 watts each
  • Cored Composite construction results in greater rigidity, increased output, reduced off axis resonances and lighter weight
  • Weather and UV resistant durable enclosure
  • Reinforced, integral suspension fly track for vertical or horizontal hanging
  • QSControl compatible for remote monitoring and control
  • Integrated heavy-duty pole cups on top and side for pole mounting top boxes
  • Diametrically opposed drivers for increased efficiency and output.

System Specifications

215PCM: Comprised of the 215SB Subwoofer Cabinet with a “backpack” containing two QSC DSP-3 24-bit Signal Processors, 1 vibration damped QSC PL230 3000 Watt amplifier and 1 vibration damped QSC PL236 3600 Watt amplifier. All interconnections for the audio signals and AC power are complete inside the backpack.

NOTE: Regular production PL230 and 236 amplifiers are not recommended replacements for the amplifiers in your 215PCM. See owners manual.
Frequency Range

Recommended Bandpass: 35 - 150 Hz (±3 dB)
Frequency Response: 36 - 360 Hz (-3 dB)
Usable Frequency Range: 29 - 440 Hz (-10 dB)
Maximum Output

Calculated Peak Output (1): 141 dB SPL
Measured Continuous Output
(2): 131 dB SPL
4 ohms (nom.) 3.7 ohms (min.) 23.3 ohms (max.)
Power Handling

1300 W RMS, 2 hours (AES)
1000 W RMS, 8 hours (IEC)
800 W RMS, 100 hours (IEC)
101 dB half-space, 95 dB full space, 35 - 100 Hz, 1W, 1m
Nominal Coverage
Omnidirectional (100 Hz)

Two 15-inch (394 mm) high efficiency subwoofer drivers.
4-inch (102 mm) voice coil, copper on fiberglass former.
High excursion, multi-vented voice coil construction.
On-board Power

Subwoofer: One vibration damped QSC PL230 amplifier in bridge mode, 3000 Watts at 4 ohms
Top Boxes: One vibration damped QSC PL236 amplifier, 2-Ch.’s, 1300 Watts per Ch. at 4 ohms/Ch.
On-board Processing
Two QSC DSP-3 24-bit, 48 kHz Digital Signal Processors. (One Processor per amplifier)

Neutrik NL4MP
Standard Bridge Mono Wiring
Pin 1+= Positive Input Signal
Pin 1–= Negative Input Signal
AC Power - NEMA L5-30 receptacle
CH1/CH2 Input - female XLR, Input 3 (discrete mono) - female XLR
Parallel Out (discrete mono) - male XLR wired directly in parallel with Input 3 connector
Output to Top Boxes - two Speakon NL4MP receptacles:
CH1 wired for 4-wire biamp use
CH2 wired for 2-wire (right channel) normal use
Both Processors feature:
Post-Processor audio outs (3-wire, detachable terminal block connectors), one for each channel.
RS-232 port for Processor configuration using PC/laptop and QSC Signal Manager software.
DataPort ties to QSControl systems to support network Processor configuration and remote control of monitoring.
AC Power switch and MODE switch (Combination Mode/Discrete Mode)
Operating Modes

Combination Mode: Inputs are wired to both the Subwoofer Processor and the Top Box
Processor inputs. Cross feeds CH3 (sub) with CH1 and CH2 for system applications.
Discrete Mode: Use all three inputs. Top Box Processor inputs are from CH1 and CH2 Input connectors.
Subwoofer Processor input is from Input 3 connector, input is connected ONLY to Processor Input 1.
Signal Routing
Signal Routing is dependant on MODE Switch position and Processor configuration.
Other Features

Built-in heavy-duty casters and handles. Durable rubber anti-skid feet on two sides of cabinet.
Weather-resistant enclosure.
Enclosure Type
High efficiency horn-ported box hybrid, tuned to 35 Hz. Material: Composilite™ cored construction.

215PCM: 230 pounds (104.3 kg)
215SB: 175 pounds (79.4 kg)
Overall Dimensions

215PCM 40" W x 26" H x 30" D, nominal (102 x 66 x 76 mm). Refer to drawing for details.
215SB 40" W x 26" H x 25" D, nominal (102 x 66 x 64 mm). Refer to drawing for details.
Pole Cups
Three 2-inch diameter, 6-inch deep, aluminum. Refer to drawing.
Flying Points
Four 16-inch “L-track” rails at corners. Refer to drawing.
Power Requirements 120 VAC, 50/60 Hz, NEMA L5-30 connector (230 V. model available)
Current Consumption
@ 120 VAC, typical, pink noise

Idle 2A
Subwoofer 1/8 power, Top Box idle 11A
Subwoofer 1/8 power, Top Box 1/8 power 8 ohms each channel 19A
Subwoofer 1/8 power, Top Box 1/8 power 4 ohms each channel 23A
Subwoofer 1/8 power, Top Box 1/8 power 2 ohms each channel 28A
NOTE: 1/8 power is representative of current draw with typical music program material with occasional clipping.

Digital Signal Processor Specifications
User configurable, custom DSP with software for PC. Computer connection needed only for set up.
Signal Processing
Two QSC DSP-3 Processors, 24 bit, 48 kHz, one for each amplifier
Frequency Response
at 3 dB below full scale input voltage

20 Hz - 10 kHz ±0.3 dB (XLR inputs on 215PCM rear panel)
20 Hz - 20 kHz ±0.7 dB (XLR inputs on 215PCM rear panel)
20 Hz - 20 kHz±0.2 dB (if using DataPort input on Processors)
<0.01% THD+N @ +4 dBu out
Delay (throughput)
1.00 millisecond
Dynamic Range

>93 dB unweighted, 20 Hz - 20 kHz, 1.5V, 4V and 9V sensitivity
>88 dB unweighted, 20 Hz - 20 kHz, 18V sensitivity

Amplifier Specifications
Output Power in watts
Subwoofer Amplifier (PL230 type)

Top Box Amplifier (PL236 type)

EIA: 1 kHz @ 1% THD

4 Ohms, 1 kHz, 1% THD 3000 Watts

8 Ohms per channel (20 - 20 kHz, 0.03% THD) 725 Watts
4 Ohms per channel (20 - 20 kHz, 0.05% THD) 1100 Watts

8 Ohms per channel 800 Watts
4 Ohms per channel 1300 Watts
2 Ohms per channel 1850 Watts
(both amplifiers)

SMPTE-IM Less than 0.01%
Typical, 10 dB below rated power, 20 - 20 kHz <0.015%
Typical, full rated power, 5 kHz. <0.01%
Frequency Response
(both amplifiers, without processors,
at 10 dB below rated output power)
20 Hz to 20 kHz, ±0.2 dB, -3 dB points: 8 Hz and 100 kHz

Damping Factor (both amplifiers)
Greater than 500
(unweighted, 20 - 20k Hz, both amplifiers)
-107 dB

Voltage Gain

35 dB, Subwoofer Amplifier, 36 dB, Top Box Amplifier

NOTE: Overall system gain is a function of Processor input and output sensitivity settings in software.
Input Sensitivity, Vrms
(this is the amplifier input sensitivity,
not the Processor input sensitivity)
Subwoofer Amplifier
Top Box Amplifier

for rated power into 215SB Subwoofer 1.07 V
for rated power into 8 Ohms 1.23 V
for rated power into 4 Ohms 1.07 V
Input Clipping, Vrms (both models)
10 V (if 0 dB gain in Processor signal path)
Ch. 1 and Ch. 2 gain knobs accessible via adjustment opening in the cabinet.
Continuously variable speed fans, one intake vent, two exhaust vents.
Amplifier Protection (both amps)

Full short circuit, open circuit, thermal, ultrasonic, and RF protection
Stable into reactive or mismatched loads
Load Protection (both amps)
Turn-on/turn-off muting, DC-fault power supply shutdown, clip limiting
Output Circuit Type (both amps)
2-step Class-H

QSC System Manager Connectivity
(applicable only to users employing QSC System Manager)

System Interface Compatibility
QSC DataPort amplifier network monitors

QSC DPC-X DataPort cable, male-male (various lengths are available, contact QSC’s Technical Services Department)
DataPorts Used
2 (1 per Processor)
Amplifier Status Monitor Features
Clip Indicator
AC Power

Senses channel clipping
Senses amplifier protect status
Reports standby/operate mode

RS-232 Ports
(used for configuring each Processor’s
DSP chain)

Number of Ports
Two (one for each processor)
Cable Type
Normal 9-pin serial cable, male-to-female
Maximum Length
25 feet (7.6 meters)
Communication Settings
Automatic (unless other software using port)

DSP Capabilities
(freely configurable DSP “blocks” use as many of any block until DSP “resources” are consumed)
High-Pass Filter, Low-Pass Filter, High-Shelf Filter, Low-Shelf Filter, Limiter, Compressor, Delay,
Polarity, Parametric EQ, Level Meter, 2 to 1 Mixer, 1 to 2 Splitter, Mute, Fader
Pink & White Noise Source
Variable Frequency Tone Source
Clip & Protect Indication available if operating the DSP real-time from PC
External Contact Closure Sensing (pin #9 of RS-232, operates with “Switched Gain” objects in Signal Manager software)
(1) Calculated maximum peak SPL at 1 meter distance, half-space, speaker operating at rated RMS power with 6 dB crest factor pink noise input, 35 - 100 Hertz.
(2) Measured maximum RMS SPL referenced to 1 meter distance, loudspeaker operating at rated RMS power with 6 dB crest factor pink noise input, 35 -100 Hertz.
Measurements taken at 2 meters, half-space, after 15 minutes of full power operation.

Specifications are subject to change without notice.
All specifications identical to the 215PCM with the exception of any top box electronics or connectivity.