TitaniumTroy
Well-Known Member
Here is an audio interview with a long time speaker designer (Kevin Voecks) who currently works as manager for Harmon Kardon's Luxury Audio Group. Which includes JBL Synthesis, Mark Levinson, Revel, Lexicon. http://www.hometheater.com/content/podc ... vin-voecks
For me the most interesting part is in the last quarter of the interview, where he talk about QLS. Quantum Logic Surround which is.
Three levels of QuantumLogic Surround processing are available: QLS 7.1, QLS Height mode which adds two left- and right-front height channels, and QuantumLogic Surround 3D, which is incorporated into the Lexicon MP-20 and provides five discrete height channels: left, center, right and surround channels in addition to a 7.1-channel configuration.
Unlike other derived-surround technologies, the QLS Aesthetic Engine functions in the frequency domain, rather than within the time domain – a fundamental difference that enables entirely different methods of signal processing. QLS identifies “Spatial Slices” from the soundstage of the original recording, and re-assembles them into a 7.1-channel surround sound format. In addition, QLS extracts reverberation information from the original source and re-creates multiple channels of reverberation for redistribution.
Spatial Slices can be comprised of a single source instrument, vocalist or sound effect. QLS identifies the location of the sound source within the stereo image and is then able to re-direct the Spatial Slices around the listening space in a controlled manner. QLS can create a totally stable surround sound playback environment, and working with the individual Spatial Slices enables an unprecedented level of imaging accuracy as well as a smooth, realistic tonal balance.
A brief technical description of how QuantumLogic Surround operates is as follows: a mono, stereo or multichannel audio input is processed with stream extraction, reverb extraction and signal decomposition, along with signal analysis, speech detection and mono signal detection. The resulting 13 streams – seven spatial filters and six decorrelated reverb streams – are then processed through the Aesthetic Engine and psychoacoustic modeling. The signal then goes through a mixer, which can be adjusted by the user to tailor the audio output to personal preferences. Finally, the signal is fed into a post-processor that adjusts volume and delay levels, and delivers a 7.1-channel audio output.
“We are excited to introduce an entirely new surround sound enhancement technology that is the result of intensive signal processing and psychoacoustic research by HARMAN, and that we feel significantly advances the state of the art,” said Jim Garrett, Market Manager, HARMAN High Performance A/V. “We look forward to introducing QuantumLogic Surround in a number of future Lexicon, JBL® Synthesis® and other products and providing our customers with a better and more enjoyable surround sound listening experience.”
FYI Mr. Voecks, recommends special in walls and in ceiling speakers for the rear channels. Due to the listener will always be at extreme off axis position, on walls cause a nasty reflection that cannot be EQ'd out.
For me the most interesting part is in the last quarter of the interview, where he talk about QLS. Quantum Logic Surround which is.
Three levels of QuantumLogic Surround processing are available: QLS 7.1, QLS Height mode which adds two left- and right-front height channels, and QuantumLogic Surround 3D, which is incorporated into the Lexicon MP-20 and provides five discrete height channels: left, center, right and surround channels in addition to a 7.1-channel configuration.
Unlike other derived-surround technologies, the QLS Aesthetic Engine functions in the frequency domain, rather than within the time domain – a fundamental difference that enables entirely different methods of signal processing. QLS identifies “Spatial Slices” from the soundstage of the original recording, and re-assembles them into a 7.1-channel surround sound format. In addition, QLS extracts reverberation information from the original source and re-creates multiple channels of reverberation for redistribution.
Spatial Slices can be comprised of a single source instrument, vocalist or sound effect. QLS identifies the location of the sound source within the stereo image and is then able to re-direct the Spatial Slices around the listening space in a controlled manner. QLS can create a totally stable surround sound playback environment, and working with the individual Spatial Slices enables an unprecedented level of imaging accuracy as well as a smooth, realistic tonal balance.
A brief technical description of how QuantumLogic Surround operates is as follows: a mono, stereo or multichannel audio input is processed with stream extraction, reverb extraction and signal decomposition, along with signal analysis, speech detection and mono signal detection. The resulting 13 streams – seven spatial filters and six decorrelated reverb streams – are then processed through the Aesthetic Engine and psychoacoustic modeling. The signal then goes through a mixer, which can be adjusted by the user to tailor the audio output to personal preferences. Finally, the signal is fed into a post-processor that adjusts volume and delay levels, and delivers a 7.1-channel audio output.
“We are excited to introduce an entirely new surround sound enhancement technology that is the result of intensive signal processing and psychoacoustic research by HARMAN, and that we feel significantly advances the state of the art,” said Jim Garrett, Market Manager, HARMAN High Performance A/V. “We look forward to introducing QuantumLogic Surround in a number of future Lexicon, JBL® Synthesis® and other products and providing our customers with a better and more enjoyable surround sound listening experience.”
FYI Mr. Voecks, recommends special in walls and in ceiling speakers for the rear channels. Due to the listener will always be at extreme off axis position, on walls cause a nasty reflection that cannot be EQ'd out.