Hey, you went looking for spectrograms.
It was a helpful key word for your search, no? Did you find the one with bass guitar showing the high 2nd and 3rd order harmonics?
Sorry for the multi-quote.
Complete cancellation means what will show up on the graph is only the reverberant spectrum. If that's what you mean, then yes.
Again, I think you are confusing cancellation with what is left on the graph. Cancellation is of the direct sound. What is left is reflected sound. There should be no impulse if you achieve perfect cancellation, just random noise-like spectrum in the impulse window that are the reflections.
Agreed. But I think in your earlier post, you mentioned constant directivity.
No, I haven't. Outside the sweet spot, I wouldn't expect perfect cancellation because I would be closer to one speaker than the other and the level would not be the same. BTW, my speakers are only constant directivity above 1 kHz. As much as I argue for directivity below 1 kHz, I don't have it currently
Hey, you went looking for spectrograms.
Did you find the one with bass guitar showing the high 2nd and 3rd order harmonics?
Yeah, and I haven't forgotten you trying to mark me into no upper harmonics down low in bass/baritone register - even singing the low C the only way there is no higher harmonic material is when the sound is so quiet as to be useless. Any zip at, and there's harmonic stuff over 1 kHz.
Naughty, naughty
Yeah, and I haven't forgotten you trying to mark me into no upper harmonics down low in bass/baritone register - even singing the low C the only way there is no higher harmonic material is when the sound is so quiet as to be useless. Any zip at, and there's harmonic stuff over 1 kHz.
Naughty, naughty
Ah, yes - but the vocal test was *humming* and at a low enough freq. that specifically didn't register with much output at 700 Hz (or above). (..I've done that before - so I know it can be done.)
It's largely a matter of which freq. is played for instruments with substantial harmonics (..a pure synth is one of the few that wouldn't meet this qualification, but then again - pure synth's playing that low in freq. are pretty rare.)
The real "kicker" however is - just what level is significant? That's the really important part.
I don't remember that at all. (..it's been over a decade and half since I read research on this topic.
) I also don't remember if with certain instruments we might focus more on the harmonics, and which harmonics, than the fundamental.Lot's of questions.
Anyway, here is the bass guitar (Fender) link with a few other bass instruments:
Audio Spectroscopy in the Analysis of Stringed Instruments and Their Components
Don't know what the amplitude difference is in the shading, but at least with the Fender at 55 Hz, there isn't much at all above about 850 Hz - that is still above 700 Hz though. BUT the output above perhaps 600 Hz or so may not be significant. Don't know.
pseudo hulabalaoo
how about we stick to talking about david's 700hz shait and trying to understand obviously what his test conditions were&his conclusions. (and try to note that even blumlein had something negative to say about pan-pots)
and please stay away from sociology studies of scientific knowledge, unless your willing and daring to venture into philosophy of science... +its really not relevant to this issue...
how about we stick to talking about david's 700hz shait and trying to understand obviously what his test conditions were&his conclusions. (and try to note that even blumlein had something negative to say about pan-pots)
and please stay away from sociology studies of scientific knowledge, unless your willing and daring to venture into philosophy of science... +its really not relevant to this issue...
I thought that the measurement knows no difference between direct and reflected sound. "Complete" or "perfect" cancellation would be (L-R) at least 20 dB below (L+R) for me. About -20 dB is the hearing threshold for some/most effects in the direct/reverberant field.
If that is the official definition of cancellation, you might exchange attenuation for cancellation in my last post.
Well, my speakers have constant directivity up to 9 kHz. I believe that your and panos speakers have narrower directivity in that area. My speakers are even "wider" if we look at 360° and not 180° only. So my reflections have a harder time to cancel one another in the L-R measurement.
I always thought that this level balance was an indispensable requirement for exquisit imaging. Didn't you claim that for your speakers for an extended area?
Rudolf
Cut the crap and stop making things up. You don't know anything about me and yet you act as you would. I have a speaker that is more uniform than anything you guys showed.
I did and do extensive tests and have tons of data but things aren't as simple as some here try to make it look.
Practice what you preach!
A phantom source does radiate sound, perceptually. It's the sound radiated by both loudspeakers.
You keep talking about the precedence effect as if it would be a filtering/masking process that has no impact on the direct sound. Psychoacoustics has shown that reflections have an effect on timbre and spaciousness. There is no masking.
When we look at practical implementations for a loudspeaker we don't have many directivity patterns to chooses from. These patterns determine how the room is illuminated and how reflection patterns look like. There are other factors to consider, e.g. D/R ratio, crosstalk, etc.
I'd like to discuss those topics but as long as people aren't open to challenge their beliefs I'm simply wasting my time here.
I have followed this discussion with interest for a couple of weeks, read the whole thing and it seems the last couple of days it is derailing from an interesting discussion to more personal attacks. One of the last posts I regard highly is from Tom Danley.
Lot's of people here defend their speakers and try to bent every known fact around that. While I think Danley produces some fine speakers he at least had an open mind as to what would make a great speaker for the home environment.
Too bad that's not the coarse of this thread anymore...
Lot's of people here defend their speakers and try to bent every known fact around that. While I think Danley produces some fine speakers he at least had an open mind as to what would make a great speaker for the home environment.
Too bad that's not the coarse of this thread anymore...
Correct. There are effectively only two. The problem being that whichever "directivity pattern" you choose it must be Constant Directivity, not merely Controlled Directivity. The argument here is all about the range of the (and which) "C" word.
Again correct. And the argument here is between those who think that the reflection pattern must be uniform across frequency, that is to say Constant, and those who (presumably because their speakers cannot accomplish that) argue that it doesn't matter, that merely Controlled over a limited part (that doesn't include most of speech and music) of the audio range is "good enough".
Pano posted a simple demonstration that shows it to be a fact that we easily hear direction below 700Hz. even in the presence of a full range of conflicting "directional cues" above 700 Hz. In response the "other guy" claimed that what we hear doesn't matter and fled the field.
Make of that what you will . . .
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I think that reasonably constant directivity from below 150 Hz. to above 5000 Hz. is both needed and achievable (achieved, in fact).
Nothing is "perfect", of course, but a speaker that radiates over 360 degrees at 150 Hz. and 90 degrees at 5000 Hz., regardless how "good" it is otherwise, clearly fails. There is simply no way it can be made to sound "right" in a small (reflective) room. How much can be acceptably "compromised", and where . . . we can argue all day about that . . .
Thread clean up. OT posts removed.
No, I am not saying that, it is just for localization that the precedence effect suppresses reflections. Reflections do indeed influence timbre and ambience.
Please do show us your uniform speaker and some data to back it up.
I've posted plenty of measurement results for Pluto Clone that back up their imaging performance.
Linkwitz notes that Pluto and Orion sound more alike than not; and this over wide range of listening material. Linkwitz also notes that Pluto has more detailed imaging than Orion.
The outstanding performance of Linkwitz's designs is due to uniformity of radiated sound.
Do you have data for speaker with uniform sound and data for crappy speaker in this regard? Does speaker with uniform sound provide more detail when listened to? Or are you just going to ask why again?
Sure, acoustics is complex. It only becomes overly complex when thoughts stray from hard data.
Earl's a theoretical physicist. Apparently not a practical physicist. This is person that theoretically is well equipped to use "simple math" to prove my simple spherical model about sound absorption as valid/invalid.
The greater the spacial volume, the lower the energy density of noise derived from coherent source of given intensity. The bigger the space, the more time coherent sound remains, and the lower the intensity of the resultant noise. And of course the noise is being absorbed by the walls too. This is all described by system of differential equations, which crudely reduce to simple equation used in common calculation of reverberation time.
So yes, your mind is full of questions based on lots of data, but you impress upon the forum these same questions in terms of other people's observations and data. This adds overly complex layer of abstraction.
If we accept the concept of individuality, then each lives in own reality. If we accept quantum theory, we are all a part of the same singularity and we share common reality.
You surely mean that the precedence effect suppresses a bad* influence of reflections on localization. It can't possibly suppress reflections itself.
If that is what you mean, I have to disagree. In my case suppressing a first reflection from behind the speaker helped much to keep a phantom image solid in space. It had a habit to move sidewards at higher frequencies.
Rudolf
* or however one would call that
In my part of the world Controlled Directivity would be a directivity that is free from jumps at the crossover frequencies and in general rising with frequency.
If such controlled directivity is achieved, I would look at the room first. Depending on the room situation (and what I'm allowed to change/improve or not) I would decide whether I need completely constant directivity or if rising directivity alone would suit the situation better.
Rudolf