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Old 13th August 2019
Lives for gear

So you don't even understand the difference between placing the speakers IN the front wall, which is a kind of perfect aligned wavefront, versus placing them NEAR the front wall and immediately catch a reflection, because the speaker cone is not aligned with the reflective surface, but in front of it?
You seem to miss the point, yet again (not surprising, actually: it seems to be what you do best.... ). Speakers far from the front wall produce SBIR. The further away they are, the lower the frequency. Conversely, the closer the speaker is to the wall, the higher up the spectrum it goes, and the smaller the effect becomes. The extreme case is flush-mounting (a.k.a.) soffit mounting, with the speaker baffle flush with the wall (yes, it's the baffle that you want flush with the wall. Not the cone: the baffle. I'll but you can't figure out why... ) With the speaker flush mounted, there is no SBIR... at least, not from the front wall. And if you do that entire exercise, starting with the speakers far away and moving them closer, while also adjsuting the mix position and other parameters accordingly, the stereo imaging does get destroyed. Not one little bit. Nothing. SBIR changes, for sure (see above), and there will likely also be differences in the perceived modal response, and perhaps even the real modal response. But the stereo imaging won't change. There's no reason for it to change. And since both speakers will be affected equally, the stereo image will still be the same...

On the other hand, the comments in that post you quoted correctly point out that distance to the SIDE walls can change the stereo imaging. True. If you move the speakers closer to the side walls, then that actually can shift the stereo imaging. But you seem to have misread the post, and assumed that when the author mentioned having the speakers close to "the wall", he meant the front wall. However, when you read it completely, and understand what he's saying, it's clear that he is referring to the side walls, not the front wall. He's also talking about untreated rooms, by the way....

Have you designed any room at all or is it just fake?
Way more than I care to remember actually. And been involved directly or indirectly in hundreds. As you could find out for yourself, with a little due diligence...

On the other hand, there's no sign at all that you have ever designed or built a studio, or even that you own one, or work in one...

Nobody spoke about the case of placing them IN.
Yes they did: it was me! I spoke about that, to show the extreme case, and how to get rid of front-wall SBIR.

No matter how good the rest of the room is designed, the front wall has its impact.
Try to pay attention: Here I am, all along, explaining what a huge effect the front wall has on room acoustics and how to minimize it, and there you are trying to pretend that I'm saying it has no impact at all! The only thing I said about the front wall, is that having your speakers against it does not destroy the stereo image, which is what you claim.

Why do you think companies sell stereo mics?
Oh no! Stereo mics! Crossed pairs, and Mid-Side, and all the others! Damnit! Well gosh darn it goodness gracious me, you totally got me there! Welll... not actually, but nice try. It might come as a surprise to you, to learn that stereo mics are actually just two mics next to each other, with two cables that feed two channels on the console.... and thus they are actually just a pair of mono tracks... There is no such thing as you claimed, with each mic and each track somehow encoding stereo information about the room. In reality, each mic only sees the entire room from it's one single unique point of view, and records what it sees. It's not until you send out related tracks to a pair of speakers, that you actually get a stereo image that you can hear. It's the speakers and the room that create the stereo image from the interaction of slightly differing sounds coming from both, not some mystical property of a mono track... You claim to be a mix engineer, but you don't even know where the illusion of stereo hearing comes from? You really though there was something hidden in a mono track? Do you even realize that stereo is just an illusion anyway? It's not true 3D sound field at all. Your brain creates the illusion for you, when you give it enough information, but it's easy to break the illusion... just move your head... The HRTF only works well to give you the illusion of stereo with your head stationary in the sweet spot, but as soon as you move your head far enough in any sense (rotating it to one side, for example), the illusion is broken and all you hear is a pair of speakers. Studio designers know this. Acousticians know this. Mix engineers know this. So how come you don't?

How do you want to design a room when you even havent heard of the effect of stereo and do not judge the listening situation with this in mind? That is insane.
Room design for 2.0 rooms starts with the speakers, actually. The room is designed around the speakers to create the illusion of stereo. Without good speakers properly placed in a good room, there is no stereo image. But to get back to the point: putting the speakers against the front wall does not destroy the stereo image.

And even for mono recorded material: when you take a vocal and run it into a good reverb plugin the vocal gets depth and moves to the back, depending on how the plugin is set. This is all abc knowledge and part of mixing, in the most basic form. You balance between dry, early reflections and reverb tail, plus initial delay. That requires good imaging performance.
... none of which will happen in a badly designed room, where the speakers are not placed correctly, and/or the mix position is not placed correctly, and/or the room is not treated correctly. You can get a partial illusion of stereo from badly placed speakers in a bad room, yes, but you'll never get the real thing until everything is arranged properly.

Oh, and by the way: if you run a vocal mic through a reverb unit and then listen to one track coming out if it, there's no stereo information in that track... You can't have stereo without two channels, each with a slightly different version of the original sound. That's why stereo mic work, by the way! Because there are TWO mics with TWO signals going to TWO mono tracks, then being produce through TWO speakers, each of which comes from a single mono track. I Do hope you are learning something here.

So you actually ARE willing to treat the front wall?
When it needs it, yes. But very often it doesn't need much. It's not the most important wall in the room. Especially if the speakers are flush-mounted. There's another wall that is far, far more important than the front wall. Let's see if you ca guess which one it is...

There is your magic 4 inch fiber, sadly it fails because it is only 4 inch,
You are right: it fails below about 30 Hz or so. It's really hard to build a trap from only 4" absorption that works well below 30 Hz. It is possible, but not easy. But for higher frequencies, it does very well. You should take a look at "Master Handbook of Acoustics": Everest has some good graphs in there, showing how well it works. This comes as a surprise to many people, who don't understand acoustics very well, since they seem to think it isn't possible. But it, as shown by both theory and practice.

Next time when you design a studio, test the effect of the stereo imaging with speakers at the front wall or or more distant. Or just come here in my studio and listen.
What can I say? Sadly, if you lose your stereo imaging with your speakers against the front wall, then the room must be rather badly designed, or treated. Or laid out.

My room is 5.86m long, is it still a small room?
Yes. In a room that small, there's not even any true reverberant field. So you are somewhat limited in what you can achieve...

Speaker separation is 1.75m. 1.2m is way too narrow,
What makes you think I was talking about your room? You should probably go back to post #1 on this thread, and read through it again: You'll see that I have been trying really hard to stay focused on the OP's room, and trying to keep the thread on-track, despite your efforts to run it off the rails into silliness. If you read again what I wrote, very slowly and carefully, you might be able to understand that I never suggested that he should set up and leave his speakers at 1.2m. Do read again... Do try to pay more attention. You might learn stuff.

Below 1.50m is not worth it, the sound stage sounds rather unnatural when using 6 inch to 8 inch speakers.
Only if you don't know how to set things up correctly, so that it does work, with a good stereo image and sound stage.

Speaker separation is 1.75m.
So you are saying that, because you have your speakers 175 cm apart, therefore all speakers in all rooms everywhere should also be 175 cm apart? Is that it? You are wanting the OP to set up his speakers 62 cm from the side walls, in a room 3m wide? Is that it?


Originally Posted by bert stoltenborg View Post
You are totally right, Synth, don't listen to crazy Stu..
The people here have no clue what they are talking about.
I suggest you leave this place and go back to your science-driven real world environment and leave us in our little warped solipsistic universe.
Yes yes yes! OK, very true. I retract everything, and agree that none of us know a thing about acoustics, and should be left alone to spew our silly nonsense to each other. Yes very much ! I agree! Synth should just stick to his incredible knowledge of real-world acoustic truth, and go help out all those needy folks on the audiophile forums, so they can understand things better an build better rooms and buy more expensive wire....

- Stuart -