So if I run a woofer between around 70hz and 500hz. It would not be foolish to go for a lighter cone and lower Q(bigger box), so that hopefully a better transient response is obtained?
Indeed... but as I recall in one of Earl's vidoes - Earl offered to coop with the creator of MSO - but he declined. Would have loved to see the outcome though
And another thing: I find it extremely arrogant to come here to a thread with my name on it (because I have spent more effort on this problem than anyone in the world, and invented this technique,) and tell me that I am wrong, using supporting arguments that are false. How did you expect me to react!!!
Well, apparently you do, since you seem to forget things after all these years in your "wisdom".
By definition every wave can be manipulated by the amplitude and phase of another wave. That is just how physics work.
The result is that one can change the nulls and peaks.
Even for standing waves.
Fyi, there are quite some people unsatisfied with multi-sub Geddes approach.
Since every scientist has to operate with an open mind, I would really give that "multi-sub optimizer" a change.
btw, ironic and funny you're mentioning the PhD.
Before COVID I used to coach quite a lot of PhD'ers and interns as well.
1 - this kind of attitude would lead to an immediate cancellation of the whole thesis project, mostly pulled by the university these people are working from
2 - A PhD thesis is only about one specific part, but doesn't say anything as a whole.
3 - I can say with 99.8% confidence that there is absolutely zero correlation between knowledge, wisdom an university or PhD level.
And I say this with my biggest respect and admiration of some of the people here on forum land!!
Some with absolutely zero scientific and engineering background know an awful lot more than quite a lot of some Gyro Gearloose out there with I don't know how many fancy papers.
Probably got those with a bag of milk.....
So, anyway, cheers to them, and salute!
In a real room with damping the modes themselves are complex. With complex modes there is never a complete null. This is analogous to a wave traveling in a tube with partial damping at one end. There will be a standing wave, but there will also be a traveling wave as the energy flows out from the system. The traveling wave never has a null and as such the system itself never has a null. The more damping the shallower the nulls become.
That's why I heavily damped my room at LFs.
Cone weight does not impact the transient response in a full system. If the system is flat then the transient response is perfect regardless of the cone weight. A larger box can be a benefit, but a smaller box does not preclude achieving an optimum response.
I'm done arguing with you. You have it wrong period.
I gave the "optimizer" a chance, it failed.
I expect that people respond on the subject with arguments and explaining the matter.
Or maybe realize they misreading things.
Quite often it is that simple.
And last of all, maybe realize that they are not the only one who knows a thing or two about the subject.
Mostly don't underestimate how much time some other people out there (especially on several forums) spend at least equal amount of time you have.
You have to respect them for that.
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1 - fact that somebody invented something, doesn't say anything about nowadays more modern techniques, or improvements on these ideas.
2 - there are multiple people who claim to have invented this technique
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Good argument, very strong with lots of references!
Sorry it won't work for you, it seems to work for a lot of other people.
Highly recommend it.
I see that the wave equation is complex in non-rectangular rooms with various damping applied. I see that the steady state field will dominate the sound pressure at about anywhere in the room. But the contribution of traveling waves will prevent severe nulls in correctly employed multisub systems. Damping of course helps too. The catch probably lies in the varying signal of the source, MS systems work best at steady signals. Luckily our ears are quite incompetent at low frequency sound appraisal.
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All wave equations can have complex wavenumbers, k = w/c. That's beca8use the k factor is always squared, which means that conjugate pairs are always possible solutions. It's just that we don't often see them that way because real is so much simpler.
Don't quite understand this. but if the sound is steady state then all transient signals are lost, i.e. steady state.
So we have to be clear here that for this discussion it is all steady state response.
This was the point that I was making. There can be steady state traveling waves that have no nulls.
You lost me there.
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OK, my assumptions:
I didn't write the sound field IS steady state. In standard living rooms, as you not only must agree but have documented yourself (or I must have misread it all), eigentonen/standing waves often dominate. This of course doesn't stop at the Schroeder frequency, and there is a clear relation between damping on the one hand and the distance to the source to the other. So we could argue that the sound field has steady state characteristics (more or less diffuse and more or less constant). Our ears, being pressure sensitive, anyway do judge it like that, that was one of your statements, I believe.
Back to the eigentonen clearly under the Schroeder frequency: the amplitude/time behavior is different from that from the source (being music). As our ears as well as our measuring equipment integrate over time, those effects might not be that obtrusive. But that doesn't mean they aren't there. You could calculate them, taking a simple model.
This all brought me to the roundup that MS systems do a wonderful job, be it that they do not tackle the above. We are lucky that corrections in the amplitude domain are enough to fool our ears, we probably wouldn't get away with that on frequency ranges in the midrange (second to that: we probably would to a great extend).
But then again, these all are only assumptions.
Oh
I didn't write the sound field IS steady state. In standard living rooms, as you not only must agree but have documented yourself (or I must have misread it all), eigentonen/standing waves often dominate. This of course doesn't stop at the Schroeder frequency, and there is a clear relation between damping on the one hand and the distance to the source to the other. So we could argue that the sound field has steady state characteristics (more or less diffuse and more or less constant). Our ears, being pressure sensitive, anyway do judge it like that, that was one of your statements, I believe.
Back to the eigentonen clearly under the Schroeder frequency: the amplitude/time behavior is different from that from the source (being music). As our ears as well as our measuring equipment integrate over time, those effects might not be that obtrusive. But that doesn't mean they aren't there. You could calculate them, taking a simple model.
This all brought me to the roundup that MS systems do a wonderful job, be it that they do not tackle the above. We are lucky that corrections in the amplitude domain are enough to fool our ears, we probably wouldn't get away with that on frequency ranges in the midrange (second to that: we probably would to a great extend).
But then again, these all are only assumptions.
Oh
I guess we can agree that a traveling wave by default has no nulls like we define them in standing waves (I could not resist that one, sorry).
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The problems this solves are endless.
0.5238(or 365.238 in 360.0) or 5.238 or the six sides of a hexagon in a circle that’s a cube in ‘3d’. .5238 as 3.142857 then 22/7 and 176/7 is offset just as leap treat is in 4 years as 21 is to (0.142857142) which is 1/7.
The hypotenuse if a 2:1 rectangle as 2 of the cubes (or hexagons) is .5238. The ratio of a sphere placed in a cube in Volume displaced as water is .5238. the orbit of Jupiter is offset by the 5.238 in astronomical units to earths 1.0 AU which is twice the speed of light (almost) it too uses 0.5238 log scaling back to 365.238 to 360!9’ the suns 43.7/6.955008 dimensions as ‘pi’. Circ over radius offset by the earths actual orbital offset in ‘time ‘ is completely observable in sound.
That is 1440 in 1461 (saturns mean orbital radius as hz is merely million miles or one hundred thousand to physics u it conversions of the metric/standard 864/432 and 14/7. Diameter and radius to and circumference jumped the same and we see it in 240 degrees and 4.1888 parts of 360(6.2857142) as well? It seems so .. because 3.8cm a year we have a lunar drift . And tides of a few billion years ago colision and momentum are slowly exchanging too.
The node in 6489 x 4 as 25920 is the equinox flip in axis of the planet and all of these apply to sound right now but any different ?
If I drive an 8thbirder qw pipe from both ends at 0.5326 from zero and 360 . I am forced into a window of simulation that’s incredibly unique.. once I add a certain waveguide length (0.5236) I get a perfect alignment out from 860-8600….. all in store if 860 to beyond as total void per the seconds in a day on earth minus 400.
All because of the speed of light as 29.99792458 is arc seconds to 0.5236 radian ?
What if I apply this to the subwoofers AND the room? In a car it’s a huge reflection off the windshield. But if a bass trap is located in a corkscrew at the other end … another chapter in an endless battle against outle own offset in time (and reality) as the optic nerve and brain and hearing all gave a qw pickup functions to default to I guess? That’s at the high and low end of maths too?
That box is 360 plus 30. But it’s a waveguide Shake too?it’s not just a poor like the rest . It’s a parabolic/conical 2x in 30 cm.ot item that aouhnoerfectky to 8600 and 860 from (86.4?) .
0.5238(or 365.238 in 360.0) or 5.238 or the six sides of a hexagon in a circle that’s a cube in ‘3d’. .5238 as 3.142857 then 22/7 and 176/7 is offset just as leap treat is in 4 years as 21 is to (0.142857142) which is 1/7.
The hypotenuse if a 2:1 rectangle as 2 of the cubes (or hexagons) is .5238. The ratio of a sphere placed in a cube in Volume displaced as water is .5238. the orbit of Jupiter is offset by the 5.238 in astronomical units to earths 1.0 AU which is twice the speed of light (almost) it too uses 0.5238 log scaling back to 365.238 to 360!9’ the suns 43.7/6.955008 dimensions as ‘pi’. Circ over radius offset by the earths actual orbital offset in ‘time ‘ is completely observable in sound.
That is 1440 in 1461 (saturns mean orbital radius as hz is merely million miles or one hundred thousand to physics u it conversions of the metric/standard 864/432 and 14/7. Diameter and radius to and circumference jumped the same and we see it in 240 degrees and 4.1888 parts of 360(6.2857142) as well? It seems so .. because 3.8cm a year we have a lunar drift . And tides of a few billion years ago colision and momentum are slowly exchanging too.
The node in 6489 x 4 as 25920 is the equinox flip in axis of the planet and all of these apply to sound right now but any different ?
If I drive an 8thbirder qw pipe from both ends at 0.5326 from zero and 360 . I am forced into a window of simulation that’s incredibly unique.. once I add a certain waveguide length (0.5236) I get a perfect alignment out from 860-8600….. all in store if 860 to beyond as total void per the seconds in a day on earth minus 400.
All because of the speed of light as 29.99792458 is arc seconds to 0.5236 radian ?
What if I apply this to the subwoofers AND the room? In a car it’s a huge reflection off the windshield. But if a bass trap is located in a corkscrew at the other end … another chapter in an endless battle against outle own offset in time (and reality) as the optic nerve and brain and hearing all gave a qw pickup functions to default to I guess? That’s at the high and low end of maths too?
That box is 360 plus 30. But it’s a waveguide Shake too?it’s not just a poor like the rest . It’s a parabolic/conical 2x in 30 cm.ot item that aouhnoerfectky to 8600 and 860 from (86.4?) .
Attachments
6 of the same circle will surround one perfectly. But in 3d as sphere it becomes 12. If tiu look at the volume of a Sphere I natybbs it’s 3,4,5,6… abd240 dinensin versions it gets stake at about 5.25 in the ongoing factor of 0.5, 1,2, 3.142857, 4.1888, 5.2…. It flattens out as the acruing size in 1,2,3,4,5,6… of volumetric
cm3 cubed, cubed.. cubed. Just like with harmonic cycles?
But start in the box (one qw path) before the big box 3 more from
The opposite side of the driver ) and then the biggest box is the rooom? But it’s got miners to work with instead of random messes?
A hexagon as 30 degrees in 180 at each side (last pic) is a ot of phase angles from everywhere ? You can draw this ? But also it’s offset in a box by one cube in 9 or 3 of them grouped. Make it all 30 cm and it’s seer okay unique to 360 and offset of 1440, 720, 1080 is the same as leap year. And (the math and simulation say it’s ‘perfection’? It’s working the 0.3492 of 7. As it’s does in qw pipes in 4th order offset driver entry. (Odd harmonic ?)
cm3 cubed, cubed.. cubed. Just like with harmonic cycles?
But start in the box (one qw path) before the big box 3 more from
The opposite side of the driver ) and then the biggest box is the rooom? But it’s got miners to work with instead of random messes?
A hexagon as 30 degrees in 180 at each side (last pic) is a ot of phase angles from everywhere ? You can draw this ? But also it’s offset in a box by one cube in 9 or 3 of them grouped. Make it all 30 cm and it’s seer okay unique to 360 and offset of 1440, 720, 1080 is the same as leap year. And (the math and simulation say it’s ‘perfection’? It’s working the 0.3492 of 7. As it’s does in qw pipes in 4th order offset driver entry. (Odd harmonic ?)
Attachments
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6 circle will surround one perfectly. But in 3d as sphere it becomes 12. If tiu look at the volume of a Sphere I natybbs it’s 3,4,5,6… abd240 dinensin versions it gets stacked at about 5.25 in the ongoing factor of 0.5, 1,2, 3.142857, 4.1888, 5.2…. It flattens out as the acruing size in 1,2,3,4,5,6… of volumetric
cm3 cubed, cubed.. cubed. Just like with harmonic cycles?
But start in the box (one qw path) before the big box 3 more from
The opposite side of the driver ) and then the biggest box is the rooom? But it’s got numbers in sync to work with instead of random messes?
If we look at more than 360 as 365.25 we see the 1461 at Saturn(not 1440) . Or 1433. Or more as that Elipse I so shape has no offset . Not we can do that ? In the speaker duct? And the room?
I find a 1.75” elipse fits a 6x6 cube ironically.? Also the Elipse is 22x44mm /7 ? Look at this metric to standard issue and they overlap in sim system that’s hard to see why nobody would?
cm3 cubed, cubed.. cubed. Just like with harmonic cycles?
But start in the box (one qw path) before the big box 3 more from
The opposite side of the driver ) and then the biggest box is the rooom? But it’s got numbers in sync to work with instead of random messes?
If we look at more than 360 as 365.25 we see the 1461 at Saturn(not 1440) . Or 1433. Or more as that Elipse I so shape has no offset . Not we can do that ? In the speaker duct? And the room?
I find a 1.75” elipse fits a 6x6 cube ironically.? Also the Elipse is 22x44mm /7 ? Look at this metric to standard issue and they overlap in sim system that’s hard to see why nobody would?
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6 circle will surround one perfectly. But in 3d as sphere it becomes 12. If tiu look at the volume of a Sphere I natybbs it’s 3,4,5,6… abd240 dinensin versions it gets stake at about 5.25 in the ongoing factor of 0.5, 1,2, 3.142857, 4.1888, 5.2…. It flattens out as the acruing size in 1,2,3,4,5,6… of volumetric
cm3 cubed, cubed.. cubed. Just like with harmonic cycles?
But start in the box (one qw path) before the big box 3 more from
The opposite side of the driver ) and then the biggest box is the rooom? But it’s got miners to work with instead of random messes?
cm3 cubed, cubed.. cubed. Just like with harmonic cycles?
But start in the box (one qw path) before the big box 3 more from
The opposite side of the driver ) and then the biggest box is the rooom? But it’s got miners to work with instead of random messes?
To my understanding - standing waves is an acoustical issue, so we need to address it with an acoustical solution, like a huge bass-trap. No amount of EQ or amount of subwoofers can remove standing waves like proper damping - simply because - the room is still the same room, even though you play a different tune in it.
I tried MSO several times. And it's a good idea, but also tricky to use and the suggestions from the software, sometimes comes up with values, like +15dB here and -20dB there. It's like brute force anti-correction and not a more clever and smooth approach. Only a week ago, I adjusted a system with two 3-way main speakers and 2 subwoofers. MSO tried to come up with all kinds of wild suggestions - and as you pointed out earlier, only 3dB gain, requires a lot more power and headroom.
Instead, I went in and measured the combined response of both subwoofers and mains. Then focused on the slope of the mains, and the slope of the subwoofers, according to their placement in the room with respect to the seating position, so that a minimum of suck-out was represented. Finally, I applied some EQ that was not excessive, but still focused on the biggest peaks. In a way - less is more.
I also tried many of the FIR options, where they claim to "take out the room"... which just "kills" everything that was good about the original recording.
Yes in the mathematical sense. But in reality, if the system (speaker, room) is not minimum phase, the above is not valid anymore.
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