Is there evidence that audible levels of nonlinear distortion are primarily heard due to their tonal balance? Eg that if they were hypothetically consistent enough with frequency and level, and monotonically decreasing, then they could be to some degree compensated by tilting the response?
I think I am wrong, at the very least the frequency would have to be larger than the circumference of the line. Thats one point..... So after the wave is larger enough to interact with the boundary of the line... the first antinode and coupling should start, and get strongest right before cutoff....that actually sounds more correct than my previous statement.
The question doesn't make any sense to me. What do you mean by "cutoff" - of a tube? That would be the 1/4wl point. ANd what do you mean by "coupling" - of what?
To wit; frequency is in inverse sec. and circumference is in meters, how can you compare the two?
I agree, my next thought was about frequency size, seems like it is a fallacy... wave size would have more to do with amplitude and dispersion from the source. So when we do calculations of frequency vs source size to figure out directivity it is just a matter effect rather than to do with an actual size of a frequency.
I guess if there was a size it would have more to do with the space in between nodes, than anything else.
In regards to coupling.... I assumed that there was always an airmass coupled to the driver at 1/4wl of the frequency its producing... In other words, I used to think that no matter what,. as long as the 1/4wl of the frequency being emitted is shorter than the line, the area between the driver and the first antinode, was coupled to the driver. This may be or may not be true but I am now seeing that resonance or null has to do with placing an antinode or node at the mouth of the line.
are you talking about the line or the frequency??? I think that would clear this up for me. I think that you are speaking of line dimension and corresponding frequencies . In that case, the next question logically would be how does one ever get a smooth FR if the line only resonates at harmonics? In practice we see that exponentially expanding lines do well and constant CSA lines do not.
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Just trying to quantify, sort of speak. You always hear people talk about size of the wave but without fully understanding what is meant its hard for me to visualize it. I see now that the size of waves is really the distance between the nodes and antinodes is not exactly some type of width, length, height, dimensional proportion.
I'm doing what I need to, in order to snap out of, thinking that a sound wave looks like below.... they look nothing like that. These are just figurative representations on a graph showing Amplitude and Frequency of oscillations. If one could see sound waves leaving the driver, it would look nothing like this. I'm not even certain that complex waveforms can accurate be displayed as such.... then again, its what I see in my DAW and when I hit play I hear it just fine....
Maynard, a guitar, a bass drum and snare below at the same time.. its hard to believe its all in there.
I'm doing what I need to, in order to snap out of, thinking that a sound wave looks like below.... they look nothing like that. These are just figurative representations on a graph showing Amplitude and Frequency of oscillations. If one could see sound waves leaving the driver, it would look nothing like this. I'm not even certain that complex waveforms can accurate be displayed as such.... then again, its what I see in my DAW and when I hit play I hear it just fine....
Maynard, a guitar, a bass drum and snare below at the same time.. its hard to believe its all in there.
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Hi @camplo,
i think you focus too much on academic questions instead of focusing on some additional measurements easy to do that will help a lot
for your assessment what you get out on low frequencies in your room i would start with this here
https://trikustik.at/en/knowledge/room-modes-calculator/
https://trikustik.at/raummoden-rechner/
this is what i get with my quite small room where all my equipment is collocated just now - my home office room
i will start to think about the lowest octave from 21.25 to 42.5 Hz when the 80 qm room is ready below the roof (hopefully before i die...)
i use the octave mid band frequencies
21.25 42.5 85 170 340 680 1360 2720 ...
because i like the definition of Genelec for subwoofer frequencies below 85 Hz and kickbass between 85 and 170 Hz
for the impedance measurement i found only a german site, but with good pics to understand what you have to do
https://de.wikihow.com/Die-Impedanz-von-Lautsprechern-messen
with my CLIO pocket measurement system Z measurements - Y axis Ohm linear, X axis frequency logarithmic - are a piece of cake of course
- good luck, Stefano
i think you focus too much on academic questions instead of focusing on some additional measurements easy to do that will help a lot
for your assessment what you get out on low frequencies in your room i would start with this here
https://trikustik.at/en/knowledge/room-modes-calculator/
https://trikustik.at/raummoden-rechner/
this is what i get with my quite small room where all my equipment is collocated just now - my home office room
i will start to think about the lowest octave from 21.25 to 42.5 Hz when the 80 qm room is ready below the roof (hopefully before i die...)
i use the octave mid band frequencies
21.25 42.5 85 170 340 680 1360 2720 ...
because i like the definition of Genelec for subwoofer frequencies below 85 Hz and kickbass between 85 and 170 Hz
for the impedance measurement i found only a german site, but with good pics to understand what you have to do
https://de.wikihow.com/Die-Impedanz-von-Lautsprechern-messen
with my CLIO pocket measurement system Z measurements - Y axis Ohm linear, X axis frequency logarithmic - are a piece of cake of course
- good luck, Stefano
You can't which is why I would never use this kind of tube in any transducer system that I designed. Horn with poor mouth terminations also have this same problem which is why the mouth termination is so critical.
Trust me it's all there. That's why the frequency domain is so valuable because then things can be more easily sorted out.
I take it you mean a constant csa tube. How/Why does an exponential flare optimize the resonance? I would guess the ever increasing CSA lowers the pressure differentials at the antinodes. Or is it all just a matter of termination?
True on the first two, but since the third is a factor in the first two, if you get them right, then it makes the third kind of irrelevant.