JBL LSR6312SP manual Powered Studio Subwoofer System Key Features

LSR6312SP Linear Spatial Reference

Powered Studio Subwoofer

System

Key Features:

Multi-format powered subwoofer for Dolby Prologic, AC-3, DTS and other surround formats.

RMC™ Room Mode Correction pro- vides electronic control of response peaks due to room modes. RMC calibration kit included.

250 watt continuous output power amplifier.

Sophisticated LCR bass manage- ment system.

Direct LFE input with selectable 10 dB input sensitivity.

Summed output allows chaining of multiple LSR6312SP for multiple subwoofer systems.

Neodymium Differential Drive NDD™ technology with dynamic braking for extended low frequen- cy response and low power com- pression.

High density baffle for low reso- nance and stable inertial ground.

Linear Dynamics Aperture port design minimizes port turbulence and reduces power compression.

Reinforced enclosure with standardized mounting points allow mounted installation.

The LSR6312SP powered studio subwoofer is designed to provide low frequency extension and sophisticat- ed bass management capabilities in stereo and multi-channel applications where exceptional spectral accuracy and high-SPL are required. The sys- tem includes JBL’s RMC™ room mode correction circuit. The system is designed around JBL’s 252F LF trans- ducer, which uses dual voice coils and a powerful neodymium magnet. With the patented Neodymium Differential Drive NDD™ technology, power compression is kept to a mini- mum. An additional third coil located between the two drive coils acts as a dynamic brake to limit excess excur- sion and reduce audible distortion at the highest operating levels. The cone is made of a carbon fiber

polypropylene composite forming a rigid piston area supported by a soft butyl rubber surround.

A 250-watt continuous power amplifier is integrated into the LSR6312SP system and provides correct drive levels for optimized frequency response. Amplification is class A-B in an all discrete topology.

The subwoofer derives its feed from a combination of Left, Center, Right and Direct LFE inputs. Subwoofer signals can be selectively derived from the front channels or from the Direct input alone using a simple Remote Bypass contact closure switch. User-selectable settings are provided for -10 dBv, +4 and +8 dBu sensitivity. For calibration and level matching of the system, an Input Trim control can be inserted into the circuit for continu- ously variable attenuation of the system input. Additionally, the Direct input has a dedicated Input Trim. The LSR6312SP includes Left, Center and Right channel outputs to feed external satellite speakers. The LCR outputs are high-passed at 80 Hz. A ¼" jack allows connection of a Remote LCR Bypass contact closure switch. When the switch is used, full-range signals are sent to the Left, Center and Right satellite speakers and the subwoofer derives its feed from the Direct input only.

Subwoofer low pass filtering uses steep 5th order low pass sections to minimize the possibility of localization of the subwoofer’s acoustic output. High pass filtering for Left, Center and Right outputs is 12 dB/octave. For convenience, input receptacles are Neutrik “Combi” type, which accommo- date both XLR and ¼" connectors.

Six DIP switches on the input panel allow the user to precisely adjust the gain and response of the system. DIP switch one inserts a variable attenua- tor inserted into the circuit allowing the level to be trimmed from 0 to -13 dB. The Left, Center, Right and Direct inputs default to -10 dBv sensitivity. Using DIP switches 2 & 3 the user can set input sensitivity for all inputs to +4 dBu, +8 dBu or +12 dBu. A signal to any input will drive the output level of the LSR6312SP to 96 dB SPL at 1 meter.

Switch 4 inverts the signal polarity of the subwoofer feed. This is used to correct for placement mismatch between the subwoofer and satellite spac- ing. Due to the varied placement options available in audio production environments, it is suggested that this switch be adjusted after the final placement of the system has been determined.