DSP can get you part of the way quicker, but the game hasn't changed. The old way encourages you to put in the hard miles and find the acoustic issues. DSP encourages you to remain seated and tweak, which eventually becomes a dead end.
It may take months or years. You don't just measure reflections, one by one you find their source, you determine their fate, you design a solution.
Sound travels through air in positive pressure waves, or bursts of pressure.
So a closed box speaker can only properly transduce half of the sinus, the positive part. The negative part is lost in the box. Yes, I think half of the signal is lost. This is also the argument for dipole speakers I'd guess.
I think that 1 electrical signal, needs to be transduced by two speakers. The other one needs to be out of phase electrically. Out of phase just means "the other phase" in my thinking.
If you would take another box, invert polarity, you can transduce the negative side of the sinus. This is 2-dimensional audio with a single electrical signal.
Dipole can never transduce these two signals at the same time without cancellation. Delayed reflections might give you a hint, of what is actually lost in translation....
Take a look at my thread in the Lounge about my experiments.
It comes down to that I split the 2 electrical signals of stereo, into 4 audible streams of sound. Then, all dimensional information is suddenly revealed in a recording
When everything is dialed with this optimum phase/timing delay thing that’s been recently discussed there is a point where slight changes in the phase relationships that actually move center left/center right, depth (particularly vocals)fwd and back. On some recordings individual instruments can be moved....I suppose that’s due to recording techniques or maybe the certain freq band....dunno, all I do know is it’s certainly not my imagination, it’s repeatable; and actually how I fine tune things.
Apropos posts 47 and 48, all I can say is, that elegant bit of high-school geometry logic is entirely kaput when your cleaner moves your speakers an inch while you are at work. Goodbye precise phase. The real world of acoustics just isn't simple like a Euclidean proof. I often can't decide in careful testing by ear and mic what polarity of my subs sounds best, let alone phase.
I wish people on this forum would stop mentioning phase, at least for anything except sub-woofers. On recordings and in rooms, phase is all over the place and people can't detect phase anyway not even members of this forum.
if you don't believe me, just use DSP to move time-alignments about and see for yourself.
B.
I wish people on this forum would stop mentioning phase, at least for anything except sub-woofers. On recordings and in rooms, phase is all over the place and people can't detect phase anyway not even members of this forum.
if you don't believe me, just use DSP to move time-alignments about and see for yourself.
B.
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Thing is you can’t really hear a difference until you get to a certain very fine line then you can focus in/out of that small window. When your there you know......I’d just like to be able to figure out exactly what’s happening in a measureable way but for now it’s easy enough just to dismiss the anomaly.
No, sorry, the negative part is produced when the diaphragm moves back.
Sound Waves as Pressure Waves
The argument for dipole speakers is constant directivity, mainly.
Appreciated. The first paragraph speaks to me.
About that negative movement: it doesn't translate well into particle excitement IMO.
Look at the animations over here:
Wave Propagation
The negative pressure part of the wave is a lot less pronounced than the positive one. Now I could be oversimplifying, or there could be audible vacuum pockets travelling through the air, or those animations are way off from reality.
Now the extra speakers I use in this experiment can't deliver negative pressure either. Phase differences between arrival at the ears must be a cue for this then, because I can hear the effect of it.
A strange thing I noticed is that, even though the speaker behind me on the left, actually plays inverted right signal, I can't tell that it does. That reminds me of the first paragraph of your link. I imagine myself being in the center of the recording, with waves and anti-waves propagating from me. While in fact, the opposite is true.
That seems like a valid reasoning. Haven't seen a lot of examples with heavily dampened walls behind those, so the 'side effect' reflections look like they are welcome to stay, or am I wrong?
this all doesn't seem to be the most popular topic but anytime I see something described that applies to what I've been trying to figure out needs investigation.
so this imagining that your in the center of the recording sounds a lot like what I was describing as being in a snow globe of music.......is that along the same line because your description fits mine to a T.
now if it is, how would you equate the same effect from just two speakers? reflection must have a lot to do with it......my back wall during testing was only 3 feet behind me and speakers were head level 9 feet out.
Reflections are welcome if they are sufficiently delayed and/or diffused. Linkwitz Lab site contains all you need to know about dipoles.
Yes, that is what it feels like.. The globe has no definite 'edge' in my experience.
Image is uniform, 360 degrees all around. You can close your eyes and 'look around' in this space.
I suggest looking at the Blumlein pattern, try make the speakers and its back reflections beam right across you. You essentially want yourself, at the listening spot to be at the center of this 'out of phase' pattern. I hope you will succeed!
Reflections are welcome if they are sufficiently delayed and/or diffused. Linkwitz Lab site contains all you need to know about dipoles.
Thanks. I think I now understand what could be the target, see my last post.
I hope this will make a more clear target for others too.
Ever listened to a recording without reverberation being added, it generally sounds flat.
Add a bit of reverberation and suddenly the acoustic effect makes the recording more listenable and engaging. Delayed reflections along with reverberation gives the effect of 'spaciousness' which we perceive as acoustic depth. As someone said previously, acoustic phase is all over the place once sound is propagated into the room. Optimizing the acoustics of the room is really a necessary part of it all if you want to 'be there' in the recording, most of us though just live with the compromises of our living spaces.
C.M
Add a bit of reverberation and suddenly the acoustic effect makes the recording more listenable and engaging. Delayed reflections along with reverberation gives the effect of 'spaciousness' which we perceive as acoustic depth. As someone said previously, acoustic phase is all over the place once sound is propagated into the room. Optimizing the acoustics of the room is really a necessary part of it all if you want to 'be there' in the recording, most of us though just live with the compromises of our living spaces.
C.M
So what i’m finding while dialing in with dsp/phase/delay/eq (all things otherwise the same) is a fine tuning of the speaker/room/lp relationship to a point closer to or reaching perfection? This kindly makes comments about not being able to hear phase changes invalid as the end result @lp is definately noticeable and preferred imo.
My settings are much different from the auto mic correction though.
My settings are much different from the auto mic correction though.
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