It is good that you point the semantics, you are right diffraction happens and we can't change that, its just sound going around an obstacle and we can only remove it in a loudspeaker concept by putting speaker inside a wall so sound cannot go around it. This is moot though, there is going to be at least one baffle step and possibly other issues further up in frequency.
How would you minimize diffraction on a speaker thats not inside a wall? how would you evaluate if you succeeded at that or not? This is the relevant question, and I think its enough to lool at effects of diffraction on frequency response.
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So one of them will show diffraction ripple starting at a higher frequency than the other...
It really can depend on the faceplate profile, whether it modifies the tweeter wavefront propagation. Typically, a basic flat faceplate will enable the baffle to have more of an affect on FR and ripple than a faceplate with some sort of a waveguide profile ie. Morel's IDR faceplate design. This isn't however a hard rule.
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Sure, I can agree with that. The assumption made a few posts ago was that a tweeter without a baffle would not show diffraction...
It would still depend on the shape of the face plate, but with the examples shown, one will show diffraction ripple at a higher frequency (the smaller one) than the other...
It would still depend on the shape of the face plate, but with the examples shown, one will show diffraction ripple at a higher frequency (the smaller one) than the other...
I have just shifted and its taken damage I am not big in cosmopolitan sorry ,can"t work out the interface to add a comment with pic but this is where I bailed from sphere to box,it still has the beautiful centre stage like a sphere but less beaming IMO
Michael here,. Have made oval shaped cabinets out of concrete. I used chicken wire doubled up to reenforce. Quite challenging to get the mix just right.. use drier than you think then spray more on after initial shape. Make sure and do the entire forming at one time because it won't want to bond well after part of it dries.They are obviously extremely heavy but zero resonance. One big hint use a concrete bonding agent in mix. Add color to the mix or stain. I stained because you can make some cool color contests. Try it if you don't care about messing up first time. The rounded shape sure does fhelp with baffle step and diffraction. Good luck Michael marmarasmichael@gmail.com
One of the things I am not sure speaker manufacturers do is consider diffraction in designs of the front of their drivers?
Back to the wall comment(s), the notion that a driver mounted in a wall ("infinite") would assume that if someone played a trumpet through a hole in that wall (same size as mouth of trumpet) it would not affect the sound vs. the trumpet in free space.
Trumpet has all sorts of harmonics not directly related to the output of the mouth and is designed to work in a 4π space not a 2π space so of course it will sound different. Bad analogy.
dave
dave
Gave them to friend years ago Only made 1 pair not very pretty I must say especially where driver connects. Wife hated them Sounded ok used SB mid woofer and their ring radiatar tweeter. Ported in back. Have picture of new transmission build if interested Thanks Michael marmarasmichael@gmail.com
Indeed, p10 already mentioned it but comparing (the job of) instruments to speakers never works out that well. The trumpet you want to mimic with the speakers is recorded "in a space" or one (the suggestion of space) is added/created artificially in the mixing/mastering stages. The speaker's job is to play that recording faithfully. Not to mimic the instrument itself in any way, but to do justice to all facets of that recording. So it is playing the trumpet, as recorded in 4pi, with the available environment sound be it a real space or a created one.
If you really want to get closer to that original sound, as it was recorded, a proper studio setup with in-wall speakers (monitors) wouldn't be a bad choice at all. That's why it is pretty common in that world. I don't think it is the ideal for home entertainment though, as the eyes do influence what we hear. But it does get rid of the diffraction/baffle step problem we are discussing here.
As said before, making sure there are no ridges/edges that the sound travels across can help more than a great deal to help avoid diffraction ripple. That works with more than one shape, as it can be applied to horn theory as well as enclosures. Don't hang on too much to the changed frequency response such a devise can have, as that is easily corrected when used/designed in a proper way. This is why there are studio speakers featuring horns as well as those using direct radiators. And the use of in-wall speakers is common in studio use as well.
I assume you're not trying to have a speaker at each instrument position if you want to listen to a full orchestra 😉. You want to hear what was picked up by the microphones and at later stage mixed properly to mimic the real event. That's what the speaker needs to reproduce. They don't mimic the instruments. That would end up being horrible. You don't want to add too many spices on top, right? That's the instrument's job together with the player. The speaker's job is being faithful to what has been recorded and mixed/mastered.
If you really want to get closer to that original sound, as it was recorded, a proper studio setup with in-wall speakers (monitors) wouldn't be a bad choice at all. That's why it is pretty common in that world. I don't think it is the ideal for home entertainment though, as the eyes do influence what we hear. But it does get rid of the diffraction/baffle step problem we are discussing here.
As said before, making sure there are no ridges/edges that the sound travels across can help more than a great deal to help avoid diffraction ripple. That works with more than one shape, as it can be applied to horn theory as well as enclosures. Don't hang on too much to the changed frequency response such a devise can have, as that is easily corrected when used/designed in a proper way. This is why there are studio speakers featuring horns as well as those using direct radiators. And the use of in-wall speakers is common in studio use as well.
I assume you're not trying to have a speaker at each instrument position if you want to listen to a full orchestra 😉. You want to hear what was picked up by the microphones and at later stage mixed properly to mimic the real event. That's what the speaker needs to reproduce. They don't mimic the instruments. That would end up being horrible. You don't want to add too many spices on top, right? That's the instrument's job together with the player. The speaker's job is being faithful to what has been recorded and mixed/mastered.
But that's exactly the point. A trumpet reproduced with a perfect (or near-perfect) speaker in a wall will still sound different than the actual trumpet. So the wall doesn't work without changing the sound.
And that's exactly where you go wrong...
You can't compare those two jobs. Production and re-production of sound are two different things.
One is an art, the other is science.
You can't compare those two jobs. Production and re-production of sound are two different things.
One is an art, the other is science.
So that's saying the folks doing the recording will always fall short - of course the "beauty of the mixing" is in the ear of the beholder. Recordings of orchestral music has to be of course in a concert hall, and typically involves many mics, the mixing blending everything down to 2 channels. But as we listen to those recordings, we want more than what might be altered by mics, we want to hear the natural beauty of the instruments and/or vocals.
But here we can talk about recording one trumpet piece in a studio, and listening to that with a good speaker in a wall vs. say in a sphere. There will be a difference, and I would contend the sphere will be both more accurate and more open / spatial. The surface of the wall does set up diffraction points just as the surface of a "box" speaker cabinet does.
Here is an interesting piece:
https://www.thescreeningroomav.com/audio-systems
If we asked the designers what they are trying to do, make the trumpet sound as real as possible, or reproduce the recording accurately, what's their most important objective? Having said that, the recording engineers should also be trying to record the music as accurately as possible, so when the trumpet is played back through the studio monitors, it sounds like the real thing.
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Wrong thinking i.m.h.o... what you add with that free standing speaker is the reflections of the space the speaker is in. Your room.
What's done in a studio with in wall speakers is to avoid adding to the sound that is recorded for mixing/mastering. They go to great length to get to listen to the recording without the added effects of the room they are in. Depending on the studio philosophy I must add, there's more than one.
You seem to want to add your room's signature to the recording and call that more faithful. It can't be more faithful, although it could be more pleasurable to your ears.
What's done in a studio with in wall speakers is to avoid adding to the sound that is recorded for mixing/mastering. They go to great length to get to listen to the recording without the added effects of the room they are in. Depending on the studio philosophy I must add, there's more than one.
You seem to want to add your room's signature to the recording and call that more faithful. It can't be more faithful, although it could be more pleasurable to your ears.
This will not work. The stereo paradigm is for reproducing the instrument in the original recording venue and it does this just fine. It is not meant to sound like it's happening in your room, and you should be careful how you allow your room to be added into the performance.