Room-Speaker setup and the importance of 5mm !

[arj]

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]

The pleasure was all mine Arj. It was a fun evening

 

[reignofchaos]

Yep thanks to Prem, my system is playing on a different level now. Bass notes are perfect, the tone of voices is unbelievable and I am getting a properly holographic 3d stage with multiple layers of depth. The only time before I heard this was in the TAD reference setup. This is the second time I am hearing such layering and I am glad it is in my own room. My respect for these baby ATCs have gone up a few notches.

Edit: You are absolutely right about digital sources sounding fabulous. The change was much more noticeable on digital sources where suddenly everything became way more listenable. Earlier, I had already given up on digital sources.

 

[Dr.Bass]

I totally agree. There is something ethereal about a system which sounds right. Most of us get a good ballpark sound. A sound that we can live with happily (provided we are fortunate enough to have a decent synergistic setup). But for any audiophile who is a bit serious, there is always a tendency to improve things. It is probably due to the ballpark nature of the sound. We know it can be better but don’t know where to unlock.

The experiment at @arj setup with @prem playing the master chef role gave an insight into where the final knot is. Open it and music becomes free. The feeling of a room minimizes. It is like music in free air. Nothing is cut short, nothing feels added. I am very happy I learnt something new

 

[jenson]

lucky indeed!

i have been secretly hoping for Prem to visit to Indore sometime! Having someone with such a finely tuned ear and a deep understanding of acoustics can make all the difference in optimizing a music system.

 

[Fiftyfifty]

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 rpem 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 .

So well written @arj . Thoroughly enjoyed reading your post. I now have many reasons to visit you, ROC and Dr.B in Bengaluru

And @prem , get ready to travel. Invitations will pour in from far and wide. And Goa beckons

Many cheers!

 

[Fiftyfifty]

@arj and @prem, from what i understand, you keep the distance from the side walls largely fixed, while playing around with the distance from the front wall, right?
I'm often unsure about the distance from side walls. Do you place the inner edge of the speaker at ⅓ or the centre of the baffle at ⅓? The inner edge option gives me better imaging but the centre at ⅓ sounds more cohesive, particularly with rock/pop recordings from the seventies with over-emphasis on stereo separation .

Regards

 

[prem]

Both side wall distances are fine as a starting point

 

[jmascreen]

Thanks @arj for the wonderful writeup. I have a similar room like yours with 18.5 X 13.5 X 10. I am struggling with room placement with bass overhang or room modes sucking out the bass in certain position. Let me try to recreate placement as specified above.

@prem any visit to Kochi planned

 

[sachinchavan 15865]

@arj, were there optimum distances for both speakers (from the front wall) exactly the same? Is the room even at that end? I wonder if in an uneven room (more space from wall on one side as compare to other) the optimum distances (for the two channels from the front wall) could end up being different?

 

[fLUX]

Good to know that this has helped both you & reignofchaos. How do you go about getting the first base distance, is it per the rule of thirds ? Also , did you attempt toe in post the optimum position ( reason I ask this is there can be lsome impact on the bass notes too post toe in apart from usual toe in changes) .

 

[reignofchaos]

Good to know that this has helped both you & reignofchaos. How do you go about getting the first base distance, is it per the rule of thirds ? Also , did you attempt toe in post the optimum position ( reason I ask this is there can be lsome impact on the bass notes too post toe in apart from usual toe in changes) .

Yes rule of the thirds is where we started off and then started tweaking. Toe in was not very important or consequential in my case as they have very wide horizontal dispersion. There is probably 10 degrees toed in.

 

[arj]

Good to know that this has helped both you & reignofchaos. How do you go about getting the first base distance, is it per the rule of thirds ? Also , did you attempt toe in post the optimum position ( reason I ask this is there can be lsome impact on the bass notes too post toe in apart from usual toe in changes) .

Yes start with rule of thirds as the first position..ideally take a mono recording and use only one speaker and then the next Toe in changes the image and not really the bass but one needs to be careful as it changes the position I anyway prefer no to in as tone is preferable to imaging..as long as the speakers disappear and there is depth I am fine.

@arj, were there optimum distances for both speakers (from the front wall) exactly the same? Is the room even at that end? I wonder if in an uneven room (more space from wall on one side as compare to other) the optimum distances (for the two channels from the front wall) could end up being different?

My room is more or less even hence it is the same.

I remember reading that ideally you should do each speaker individually with a only one speaker playing and that is the best as it takes care of uneven dispersion due to furniture etc.

My rack is behind one speaker and there was some imaging issue which Dr.Bass found. On prems suggestion I straightened my rack which is behind one speaker and that became ok.

 

[Phew]

Having done this myself for all my speaker placements in the past it might look tiring but is highly rewarding. As @arj mentioned the moment the placement hits 'THE SPOT' the change is instant and evident to put a big smile on one's face and reward all the effort.
Great going @arj @prem

 

[ajuvignesh]

Is this based on the principle by John hunter of rel? He start with one of the speakers to find the best place for bass and lock it there. Then he does the second speaker.
In my case, even 2mm can make or destroy the phantom center image. Now that I have minidsp shd studio, tuning is way easier.

 

[arj]

Is this based on the principle by John hunter of rel? He start with one of the speakers to find the best place for bass and lock it there. Then he does the second speaker.
In my case, even 2mm can make or destroy the phantom center image. Now that I have minidsp shd studio, tuning is way easier.

Subwoofer works a different way. I think the guy is Richard Lord right ? the principle there is maximizing bass. Hunter might have been part of the Sumiko takeover of REL.

This is similiar the Rule of third or Cardas. since it is never precise thats your starting position. just like the Wilson WASP method you need to move speaker to the right point by ear. Its actually physics and if someone can measure whatever needs to be measured I am sure it can be found that way.

EQ works a different way..it attenuates frequencies and could result in harmonics loss usually preferred ( by me) once you have already found the Audio sweetspot and then use it it finetune either electronically or by absorber/diffusers

 

[jmascreen]

What was the sitting/sweet spot while testing?

 

[jenson]

three queries-

1. is it possible that left and right speaker need not be exactly symmetrical (depth/distance), that one can be slightly forward than the other? assuming such scenarios where furniture placement across right wall may be completely different that what's placed on left.

2. getting vocals centered, is that a start? what else does it indicate wrt starting point.

3. snaps into position - i am assuming it feels like how one tunes a instrument, that feeling can only be experienced, however in this case, any more hints...? does it primarily have to do with bass?

 

[prem]

The voices and instrument tones should sound correct. I don’t look for any other attribute. That’s how I do it at all places. I normally set it up with both speakers operational.

I also don’t look for any sudden lock in of the sound. I try and make sure there is no exaggeration of any frequency. Listening to instruments like flute, cymbals, etc, gives a good idea of whether you are in the zone. I normally use flute, whistle, voices etc to set up a system.

I don’t work on any sweet spot. I try and make sure it sounds good in any part of the room.

At ROC’s place I heard a little splash of the cymbals in the right speaker. Hence pushed it back by 5 mm. It got sorted. So at his place I don’t know if the speakers are in a perfectly straight line. I prefer starting with them in a straight line

I do the whole set up purely by ear

 

[prem]

three queries-

1. is it possible that left and right speaker need not be exactly symmetrical (depth/distance), that one can be slightly forward than the other? assuming such scenarios where furniture placement across right wall may be completely different that what's placed on left.

2. getting vocals centered, is that a start? what else does it indicate wrt starting point.

3. snaps into position - i am assuming it feels like how one tunes a instrument, that feeling can only be experienced, however in this case, any more hints...? does it primarily have to do with bass?

My room is a complete mess. It has curved french windows behind the speakers. The right side opens up completely. If you look at it it’s kind of a nightmare. But my speakers are in a perfectly straight line, parallel to the side walls.

To start with I don’t look for any centering of vocals. I only concentrate on the tone. It should sound open. In most cases voices sound restricted if placement is not correct.

I use zero room treatment