Room-Speaker setup and the importance of 5mm !

An even more difficult adjustment is the speaker height and ear height. After all, the floor and ceiling are walls too! It's not just the relative heights - the absolute heights also matter. In my room, there is a significant difference in sq when standing vs. sitting. And I've observed this in other people's rooms as well.
With the JBL 4343, I am surprised you are having this problem. Both horizontal and vertical dispersion of the 4343 is very good.
 
With the JBL 4343, I am surprised you are having this problem. Both horizontal and vertical dispersion of the 4343 is very good.
Yes, but i suppose the ceiling and floor reflect differently. And if distances from other walls are important to an accuracy of 5mm, wonder how can ceiling and floor distances can be less relevant
 
I have never faced this problem. So don’t have any solution :)

Normally it’s recommended to have the tweeter at ear height while listening, especially when it’s a multi way like the 4343.

With a single driver that’s not critical.

A carpet on the floor usually takes care of reflection of high frequencies from the ceiling. Problem arises when high frequencies keep bouncing between two parallel walls.
 
I have never faced this problem. So don’t have any solution :)

Normally it’s recommended to have the tweeter at ear height while listening, especially when it’s a multi way like the 4343.

With a single driver that’s not critical.

A carpet on the floor usually takes care of reflection of high frequencies from the ceiling. Problem arises when high frequencies keep bouncing between two parallel walls.
Let's see how we can fix it when you are in Goa next :)
 
We all understand that the room is the most critical component of a music system, though many of us might not fully appreciate its impact. I was no different. While experts often emphasise precise speaker placement down to 4-5mm and its effect on sound, I only started noticing changes at around 5-6 cm.

In my discussions with prem he would always mention about his speakers locking in by movements of 5 mm and could never really comprehend it ! Last week, Prem was in town and I experienced this firsthand in my own home and felt compelled to document it before I forgot :)

One crucial concept to grasp is how frequencies interact with the side and back walls. According to theory, certain nodes in the room allow the speaker to lock in, minimising bass overhang, preserving mids, and ensuring smooth, well-timed music flow. Typically my placement was with speakers about 2.1-2.2m from the back wall and 4 ft from the sides (one-third), achieving good bass response. However, certain albums like Nikaah and Aandhi always sounded shrill in the high frequencies with weak bass, which I attributed to the recording quality. Most of my friends in Audio agreed

So when Prem offered to help setup my room I jumped at the chance . At the end the transformation was remarkable when we adjusted the speaker position to find the "The Spot." which was between 3-5mm only beyond which the balance of music changed

Getting into the details, my room measures 18 ft by 12 ft with a 10 ft ceiling. It's rectangular with doors behind the listening position and a large window behind the speakers. Using a digital distance measurer, we ensured precise adjustments, typically done by ear.

We started with one speaker, playing a single channel to make it easier for me to grasp what Sensei Prem was hearing. Initially set at 2.2m, the balance was off with high frequencies too prominent, bass weak, and mids cut off. Prem directed and I gradually moved the speaker back by 5cm increments until we found the right spot at around 2.05m. Then, fine-tuning with 5 mm adjustments, at approximately 2.053m, the room acoustics just locked in. The moment I moved the speaker, I could detect a subtle "click" in the sound quality.

We repeated this process with the second speaker, and put the music on stereo and suddenly, the music flowed seamlessly.

We then tried this setup at @reignofchaos place with his ATCs. Both ROC and I quickly identified the point where the music just flowed while Prem directed the positioning - it took about 30 minutes to find the optimal spot and the result was really surprising.

Later, @Dr.Bass joined us at my place, and we repeated the process again in my room. All three of us pinpointed the same spot, with noticeable improvements again and locked the place in. In the end, Aandhi sounded balanced without the shrillness, and Nikaah revealed only Salma's natural nasal tone. Mahendra Kapur’s voice never sounded so heavenly. Jazz and rock on digital sources sounded significantly better. Interestingly, the bass further improved after 5-6 hours.

Anyone who has visited Prem’s house and listened to his system knows how incredible it sounds. While the equipment choice is exceptional, the coup de grâce is the precise speaker positioning.

Quoting Prem, "Components are like ingredients for a dish, but making a dish taste good requires a skilled cook." I would add that even with the exact recipe, you still need a fine-tuned ear to get everything just right and since Prem has it, it was my luck that he was in town with the time to "lend me his ears " ☺️

Here’s to finding the elusive M-Spot 😇 . my room is at 2.053 which I have inscribed in my brain and now in this post .
Prem set up my old saadhanas , once he visited kolkata. After my room changed . I tried a lot of placements, I still think my speakers are being deprived of its rights! Prem when will u be in Kolkata!!!!
 
Being in Mumbai, I think i may get access to Prem only after he has toured India :D
 
An even more difficult adjustment is the speaker height and ear height.
It helps when bookshelf speaker manufacturers make matching stands for their models. In my case, buying the Castle Knight stand with the CK2 proved to be a costly, but well worth decison. The combined height (at the tweeter) matches the ear level for someone like me with average height sitting on a conventional couch. The other option is to get custom-built stands of your listening height is non-standard.

I imagine most floorstanders are designed to have tweeters at a similar height. I have seen taller speakers which have the tweeter section at a downward angle… with those it might matter how far away from the speaker you are sitting, I imagine.

In my room, there is a significant difference in sq when standing vs. sitting.

I wonder if that makes a bigger difference for FS (since there are multiple drivers and big distance between topmost and bottommost driver) than for BS!

Double sided tape in my case
I’ve seen Prem using L-shaped cardboard cutouts with markings on it that can be set against the wall, extending to the speakers for quick adjustment. I employ the non-innovative method of measuring and noting distances from the walls and the (unavoidable) cabinet between the speakers.
 
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But is it not rare that one ends up sitting in exactly the same position each time to listen to music? So if my head is off axis by 5 mm to the left or right the image will be affected ? Then does the 5 mm adjustment still hold true ? Also the items in the room keep changing (not the large ones) but smaller ones (a school bag on the sofa, an extra mat on the floor). Does this not impact the precise measurement / adjustment done earlier ? The speaker is not just interacting with the room but with the ears as well ? So rather than adjusting speaker placement which is rather difficult in Mumbai can seating adjustment work ?
 
Amarendra, correct speaker placement will only help you reduce effect of room nodes.

Sweet spot is more a function of the dispersion of the drivers in the speaker.

Some speakers have a wider dispersion angle which allows a wider sweet spot. Some are very controlled dispersion where the sweet spot is reduced.

With a wider dispersion there will be more of reflection.

If your speaker design is such that it demands you sit exactly at one position and listen, then that’s not going to change with optimum speaker placement.

As I mentioned earlier, speaker placement is only a tool to reduce effect of room nodes. You can also use digital room correction, absorbers, diffusers, resonators to achieve the same.

But the right approach is to get the placement right and then address room issues, if they are still present.
 
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When you guys are talking tone, what exactly are you referred to? I'm genuinely interested in knowing. To me tone is primarily intensity and timbre aka quality of reproduction of frequencies. I find it hard to wrap my head around posts talking "tone" and "timbre", "tone" and "bass" in the same sentence (breath) as if they are different. I happen to believe that timbre is a major part of tone and bass also has timbre and hence has tone. I'm happy to stand corrected though if I might be incorrect in my belief so please free (in simple sentences please).

I also believe that tone is affected depending on where you are hearing it in the room. If anyone says otherwise, it's like saying: if you are listening behind your speakers as opposed to listening in front of your speakers all audiophiliac attributes like imaging, height, depth, spaciousness etc will be affected (as it should) but tone will not - and this has not been my experience at all. But then it all boils down to a fact whether my interpretation of tone is correct in the first place so, have a go at me.
 
Keith, there are many ways to skin the cat. What I do is what works for me. I have always found that at one precise position in the room, the room node effect is drastically reduced.

The biggest culprit in any room is the bass. The moment it rides on a frequency, tone and timbre goes for a toss. When you push the speakers behind, the bass output will increase but it will definitely ride on some frequencies. This affects the tone and timbre. Harmonics get reduced. Tone becomes deeper. Attack reduces.

To control bass, you can use DRC or absorbers. I prefer not using them because IME, they affected the timbre. So I prefer finding the right spot in the room to reduce room effect.

It’s as simple as that. As I mentioned earlier there are many other approaches to achieve the same.

It’s just that I was in Bangalore and set up a couple of systems. Otherwise I never do it because people hear differently and have different approaches to setting up a system.

The way I set up is strictly for myself because that’s what i found as an optimum solution. And I am not here to debate the merits and demerits of my approach. :)

At the end of the day it’s just a hobby for me, highly subjective, with nothing right or wrong. Do what works best for you
 
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Keith, there are many ways to skin the cat. What I do is what works for me. I have always found that at one precise position in the room, the room node effect is drastically reduced.

The biggest culprit in any room is the bass. The moment it rides on a frequency, tone and timbre goes for a toss. When you push the speakers behind, the bass output will increase but it will definitely ride on some frequencies. This affects the tone and timbre. Harmonics get reduced. Tone becomes deeper. Attack reduces.

To control bass, you can use DRC or absorbers. I prefer not using them because IME, they affected the timbre. So I prefer finding the right spot in the room to reduce room effect.

It’s as simple as that. As I mentioned earlier there are many other approaches to achieve the same.

It’s just that I was in Bangalore and set up a couple of systems. Otherwise I never do it because people hear differently and have different approaches to setting up a system.

The way I set up is strictly for myself because that’s what i found as an optimum solution. And I am not here to debate the merits and demerits of my approach. :)

At the end of the day it’s just a hobby for me, highly subjective, with nothing right or wrong. Do what works best for you
I don't understand where you are coming from with this. I have NOT questioned or debated your approach towards what you are trying to achieve. I have not done that for others approaches too leave aside what is right or wrong. In fact I admire your and others involved approaches towards the pursuit of attaining better sound in your rooms and your involvement in others rooms too. My post was not about you or me or any approach and what works best for me. As a matter of fact, I have zero bandwidth to play around in my room and speakers towards even attempting what you do - for various reasons that are my own.
My post was a simple one about tone.
My apologies to all if my post was convoluted that it didn't come across as simple. :)

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The biggest culprit in any room is the bass. The moment it rides on a frequency, tone and timbre goes for a toss. When you push the speakers behind, the bass output will increase but it will definitely ride on some frequencies. This affects the tone and timbre. Harmonics get reduced. Tone becomes deeper. Attack reduces.

To control bass, you can use DRC or absorbers. I prefer not using them because IME, they affected the timbre. So I prefer finding the right spot in the room to reduce room effect.
This part is much appreciated and is relevant in educating me, so, Thank you for this!
 
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Keith, my reply of not wanting to get into a debate was not directed towards you. It was in general. Mine is not a scientific approach. So it can always be debated. It’s just that it works for my ears and I see no point in getting into a debate on that.

Apologies if you thought it was directed at you
 
Keith, my reply of not wanting to get into a debate was not directed towards you. It was in general. Mine is not a scientific approach. So it can always be debated. It’s just that it works for my ears and I see no point in getting into a debate on that.
No debate at all and my intent was not to get into one. My intent was for others and maybe you to correct my understanding about tone if I am indeed wrong in my understanding.
Apologies if you thought it was directed at you
Actually I did think it was directed towards me because you addressed me. Glad that you clarified to the contrary. It's all good now.
 
But is it not rare that one ends up sitting in exactly the same position each time to listen to music? So if my head is off axis by 5 mm to the left or right the image will be affected ? Then does the 5 mm adjustment still hold true ?
The 5 mm adjustment is not to be understood as that for the distance between the speakers and our ears. It is for the distances between the speaker and the walls or other reflective surfaces. Once you’ve set those to the best possible in your room, a 5 mm or even 5 inches movement of your head won’t change the sound, but only the position of the image for you. Even if you haven’t adjusted the speaker position, moving your head won’t change the sound for you… just that the sound may not be the best your speakers can produce in your room.
 
But is it not rare that one ends up sitting in exactly the same position each time to listen to music? So if my head is off axis by 5 mm to the left or right the image will be affected ? Then does the 5 mm adjustment still hold true ? Also the items in the room keep changing (not the large ones) but smaller ones (a school bag on the sofa, an extra mat on the floor). Does this not impact the precise measurement / adjustment done earlier ? The speaker is not just interacting with the room but with the ears as well ? So rather than adjusting speaker placement which is rather difficult in Mumbai can seating adjustment work ?
Symmetry is critical too. Specially distance between speakers and sidewalls.
Any thing placed along one sidewall with the opposite wall being bare will affect the measurements and image
In addition there is always the possibility that it is a recording feature, a weak amp channel or compromised hearing on one side- all these can also be tested in different ways
 
Interestingly, pro audio engineers propose to start with sitting position first which is 38% from the front wall and speakers mostly mounted to the walls!. Wondering in home audio should the speakers be placed at 38% to start with as that may be devoid of room nodes..I was looking at @arj room dimension and final position ...it's very close to 38%.
 
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