So just to get it out there, i'm not an expert or anything close to that. so take whatever I say here with a grain of salt, I'm just discussing what I understood from different speaker building/purchasing trends and processing it all together.
This discussion is also for home audio, and i also mean typical everyday person home audio. So the 1% here with giant mansions this discussion doesn't apply to you.
Also, this discussion is also for people who want to share their audio experience with other people. It does not apply to people with audio rooms with one chair in the 'perfect spot', this is a discussion to have a very wide 'perfect spot' (thus the 'home audio' in the title) so more than person can enjoy the 'perfect spot'.
Part 1: Tonal Balance VS Stereo image.
This is the main compromise for people that want to have a wide sweet spot, most people purchase a wide directivity speaker that radiates equally over a wide surface so that tonal balance is maintained for everyone (flat off and on-axis response).
While this is a very interesting proposition, the stereo image suffers dramatically. the moment someone is not sitting at the center between the two speakers, the stereo image instantly collapses towards the speaker you're closer to.
While both volumes are somewhat equal, the time it takes for the sound to reach our ears is not the same. sound arrives quicker from the speaker you're closer to. this causes a shift in our perception of the sound and the image collapses to the speaker we're sitting nearest to. The SPL from the pic above represents perceived loudness.
Well how about speakers with narrow directivity (flat on-axis response)? Well this is the other side of the compromise. When you sit off center, the volume from the speakers decrease. and the farther off-axis that you sit, the worse the tonal balance become.
However, just like wide directivity, the sound from the speaker you're sitting closer to arrives before the speaker that you're sitting far away from.
Under optimal conditions, one can trade time of the sound for the intensity of the sound so that the stereo image doesn't collapse to one speaker when someone sits closer to one speaker over the other.
Basically, the center position would be just 15° off axis to both speakers (or whatever the speaker can handle without severely affecting the tonal balance). so a person sitting left center would be on axis to the speaker on the right, and 30° off-axis to the speaker on the left. This way both speakers are perceived as equally loud and center image is maintained.
With a narrow directivity speaker, if the path to the further away speaker is the most on-axis path, then center image is maintained for all people sitting equally on the horizontal plane (the sofa).
However, this is all hypothetical and many people find time intensity trading too complicated and not very practical to do in their own room and with their own speakers. Not to mention that tonal balance is not perfectly maintained to people sitting off center.
Part 2: The LXmini by Siegfried Linkwitz, is it the answer for proper stereo image and tonal balance to a wide audience?
The LXmini is a DIY speaker with a very very wide directivity that promises flat on-axis and off-axis response. the LXmini also prevents the sound image from severly collapsing (some collapse ofcourse still happens) to the speaker you're sitting closest to.
Briefly, the LXmini uses an upward firing woofer, which is omni-directional. and right above it is a dipole (a bare full range driver) that radiates to the front, and also to the back (in the opposite polarity). the Full range driver is basically an oscillating plate with the baffle removed.
When you cross an omnidirectional driver with a dipole driver, the negative phase of the dipole (radiation behind the fullrange driver) cancels the radiation to the back produced by the omnidirectional driver. The resulting response is a carotid frequency response, which is wider than a dipole, but less wider than an omni.
So basically the LXmini is an omnidirectional speaker at the low frequencies, a cardioid at the middle and a dipole at the high-end.
the pole behind the full-range also works to scatter the sound towards the listener at the high (dipole) end.
The result is (Acording to Linkwitz) a very wide dispersion speaker that radiates the entire room (except the wall behind the speakers), and the recipient percieves a stereo image that is not hard bounded by the speakers, the stereo image spreads smoothly between the speakers and extends well beyond the edges of the two speakers. Also the auditory scene is not very crunched to one speaker when you sit off-axis on the horizontal plane.
What are your thoughts on this? Do you agree that the LXmini seems like a good solution to achieve a good stereo image and tonal balance?
This discussion is also for home audio, and i also mean typical everyday person home audio. So the 1% here with giant mansions this discussion doesn't apply to you.
Also, this discussion is also for people who want to share their audio experience with other people. It does not apply to people with audio rooms with one chair in the 'perfect spot', this is a discussion to have a very wide 'perfect spot' (thus the 'home audio' in the title) so more than person can enjoy the 'perfect spot'.
Part 1: Tonal Balance VS Stereo image.
This is the main compromise for people that want to have a wide sweet spot, most people purchase a wide directivity speaker that radiates equally over a wide surface so that tonal balance is maintained for everyone (flat off and on-axis response).
While this is a very interesting proposition, the stereo image suffers dramatically. the moment someone is not sitting at the center between the two speakers, the stereo image instantly collapses towards the speaker you're closer to.
While both volumes are somewhat equal, the time it takes for the sound to reach our ears is not the same. sound arrives quicker from the speaker you're closer to. this causes a shift in our perception of the sound and the image collapses to the speaker we're sitting nearest to. The SPL from the pic above represents perceived loudness.
Well how about speakers with narrow directivity (flat on-axis response)? Well this is the other side of the compromise. When you sit off center, the volume from the speakers decrease. and the farther off-axis that you sit, the worse the tonal balance become.
However, just like wide directivity, the sound from the speaker you're sitting closer to arrives before the speaker that you're sitting far away from.
Under optimal conditions, one can trade time of the sound for the intensity of the sound so that the stereo image doesn't collapse to one speaker when someone sits closer to one speaker over the other.
Basically, the center position would be just 15° off axis to both speakers (or whatever the speaker can handle without severely affecting the tonal balance). so a person sitting left center would be on axis to the speaker on the right, and 30° off-axis to the speaker on the left. This way both speakers are perceived as equally loud and center image is maintained.
With a narrow directivity speaker, if the path to the further away speaker is the most on-axis path, then center image is maintained for all people sitting equally on the horizontal plane (the sofa).
However, this is all hypothetical and many people find time intensity trading too complicated and not very practical to do in their own room and with their own speakers. Not to mention that tonal balance is not perfectly maintained to people sitting off center.
Part 2: The LXmini by Siegfried Linkwitz, is it the answer for proper stereo image and tonal balance to a wide audience?
The LXmini is a DIY speaker with a very very wide directivity that promises flat on-axis and off-axis response. the LXmini also prevents the sound image from severly collapsing (some collapse ofcourse still happens) to the speaker you're sitting closest to.
Briefly, the LXmini uses an upward firing woofer, which is omni-directional. and right above it is a dipole (a bare full range driver) that radiates to the front, and also to the back (in the opposite polarity). the Full range driver is basically an oscillating plate with the baffle removed.
When you cross an omnidirectional driver with a dipole driver, the negative phase of the dipole (radiation behind the fullrange driver) cancels the radiation to the back produced by the omnidirectional driver. The resulting response is a carotid frequency response, which is wider than a dipole, but less wider than an omni.
So basically the LXmini is an omnidirectional speaker at the low frequencies, a cardioid at the middle and a dipole at the high-end.
the pole behind the full-range also works to scatter the sound towards the listener at the high (dipole) end.
The result is (Acording to Linkwitz) a very wide dispersion speaker that radiates the entire room (except the wall behind the speakers), and the recipient percieves a stereo image that is not hard bounded by the speakers, the stereo image spreads smoothly between the speakers and extends well beyond the edges of the two speakers. Also the auditory scene is not very crunched to one speaker when you sit off-axis on the horizontal plane.
What are your thoughts on this? Do you agree that the LXmini seems like a good solution to achieve a good stereo image and tonal balance?
