Active cancellation of a height-channel soundbar array's forward sound radiation
A multi-driver multi-channel single enclosure Height-Channel (e.g., ATMOS™ or DTS-X®) enabled soundbar loudspeaker system 260 uses a novel signal processing system, driver mounting configuration ( 310 L, 310 R) and method to provide a high fidelity home theater listening experience, in a manner which relies on a new method for cancellation of unwanted direct (not ceiling-bounced) radiation of the Height-Channel (or virtual height envelopment) channel's sound 213 DS.
1. A multi-channel single enclosure height-channel enabled soundbar loudspeaker system, comprising:
an enclosure having a front surface, a top wall surface, a left sidewall, and a right sidewall;
a left height-channel direct signal cancellation loudspeaker driver;
a right height-channel direct signal cancellation loudspeaker driver;
at least one left height-channel speaker driver aimed upwardly from the top wall surface, positioned proximate to the left sidewall, and having a first acoustic center spaced from the left height-channel direct signal cancellation loudspeaker driver by a distance DL-AC in a range of 2 to 8 inches;
at least one right height-channel speaker driver aimed upwardly from the top wall surface, positioned proximate to the right sidewall, and having a second acoustic center spaced from the right height-channel direct signal cancellation loudspeaker driver by a distance D R-AC in a range of 2 to 8 inches;
left and right height-channel signal inputs, signal processing, and first and second amplifiers connected to the left height-channel direct signal cancellation loudspeaker driver and the right height-channel direct signal cancellation loudspeaker driver, respectively;
wherein the signal processing comprises a band pass filter for generating filtered left and right height-channel signals, and a phase inversion configured to invert the phase of the filtered left and right height-channel signals for generating filtered, inverted left and right height-channel signals, and
wherein the signal processing further comprises attenuation configured to provide about 3-9 dB of attenuation to generate level adjusted filtered, inverted left and right direct height-channel cancellation signals.
2. The multi-channel single enclosure height-channel enabled soundbar loudspeaker system of claim 1 , wherein the signal processing further comprises a delay configured to generate level adjusted and delayed filtered, inverted left and right direct height-channel cancellation signals.
3. A multi-channel single enclosure height-channel enabled soundbar loudspeaker system, comprising:
an enclosure having a front surface, a top wall surface, a left sidewall, and a right sidewall;
a left height-channel direct signal cancellation loudspeaker driver;
a right height-channel direct signal cancellation loudspeaker driver;
at least one left height-channel speaker driver aimed upwardly from the top wall surface, positioned proximate to the left sidewall, and having a first acoustic center spaced from the left height-channel direct signal cancellation loudspeaker driver by a distance D L-AC in a range of 2 to 8 inches;
at least one right height-channel speaker driver aimed upwardly from the top wall surface, positioned proximate to the right sidewall, and having a second acoustic center spaced from the right height-channel direct signal cancellation loudspeaker driver by a distance D R-AC in a range of 2 to 8 inches;
wherein the at least one left height-channel speaker driver comprises a first multi-element array of two to five drivers aligned on an axis and aimed upwardly from the top wall surface at a selected ceiling bounce angle in the range of 5 to 20 degrees; and
wherein the at least one right height-channel speaker driver comprises a second multi-element array of two to five drivers aligned on an axis and aimed upwardly at the selected ceiling bounce angle; and
wherein the first multi-element array comprises a phased array of drivers aligned on the axis and is, via selected delay processing, aimed upwardly from the top wall surface at the selected ceiling bounce angle in the range of 5 to 20 degrees.
4. The multi-channel single enclosure height-channel enabled soundbar loudspeaker system of claim 3 , wherein the first multi-element array comprises a phased array of drivers aligned on the axis and is, via selected delay processing, aimed upwardly from the top wall surface at a selected ceiling bounce angle of 15 degrees.