Room-Speaker setup and the importance of 5mm !

[sachinchavan 15865]

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.

@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?

Inspired by this thread I did some experimentation in my set-up yesterday with interesting result.

Before this I had already optimised my speaker position (at 30 cm from the front wall) under (online) guidance from @prem a couple of years ago. But both my speakers were at the same distance from the front wall.

After the discussion in this thread yesterday and prompted by @arj’s experiment where the individual speakers were set separately, I decided on trying this. My room is lopsided, while the side wall is about four feet from the right speaker and there’s also a doorway in the front wall that side, the left speaker is placed in a tight corner where about a foot long side wall continuing into a French window) just about a foot away from the speaker. I always experience slight booming from this speaker therefore. Even if I open the window, the corner reflects some sound.

So I decided to bring the left speaker gradually up, in increments of 2 mm each (yes, I can move them patiently with precision even in smaller increments ). I decided against setting the individual speakers separately, but go by my ears on the tone (a learning from Prem) with stereo mode on. Test material was the Guzaarish CD which I have been listening to a lot off late. I sensed an improvement and hence continued bringing the left speaker further up. It was finally till 31.4 cm that the improvement continued, after which it started disappearing. Then I moved around that point in increments of 1 mm and felt the best result was at 31.3 cm from the front wall. At this position (L at 31.3 and R at 30.0) I got the best result - the instrument tones were as real as I’ve heard in my system and the center image (vocals esp) felt more immediate/palpable.

But I couldn’t just stop there. I was losing on the lower bass as compared to before. This, I realised must be because now the average position (across both speakers) was now 30.65 cm from the front wall instead of 30 cm earlier. The solution was easy - to push both speakers behind by 0.65 cm. When I did that, the bass response (my speakers have read port) was strong enough, while the improvements in tonality and imaging were retained.

Result: The experiment has resulted in an uneven positioning of the speakers from the front wall (29.35 cm for the right speaker and 30.65 cm for the left speaker) to compensate for the unevenness of the room (to the extent I could).

I shall continue to listen to this positioning for a few days, say a week to confirm it is a real change. Though my wife (who doesn’t get into technicalities, but goes by the feel) attested it sounded more alive, I’ve seen that if a changed sound continues to engage me, making me listen more even after a week, it’s more likely to be an improvement.

P.S. I also considered angling one of the speakers instead of uneven distancing from the front wall, but decided against it. My speakers have always sounded best without a toe in. Toe in affects the soundstage and separation. The instruments sound more sublime/ethereal without a toe in.

 

[Phew]

Result: The experiment has resulted in an uneven positioning of the speakers from the front wall (29.35 cm for the right speaker and 30.65 cm for the left speaker) to compensate for the unevenness of the room (to the extent I could).

Just a possibility, maybe the speakers are now in a straight line and the rear wall is uneven. As with speakers not being in a straight line will cause time alignment issues.

This is the very issue in my room, the sidewalls are parallel with 360cm width even across but the front and rear wall are not, left side F&R is 450cm and right side F&R is 449.1cm measured from the skirting. So when measured from the front wall my speakers appear to not be in a straight line but when using laser measure its actually the uneven length of the room from left side to right.

 

[sachinchavan 15865]

Just a possibility, maybe the speakers are now in a straight line and the rear wall is uneven. As with speakers not being in a straight line will cause time alignment issues.

Not so. The front wall (the one behind the speakers in my terminology) and my sitting (the couch) are perfectly parallel as evident from the flooring tiles. So the speakers are indeed 29,35 and 30.65 cm respectively from the front wall. I don’t measure at the skirting level, but at the top of the speaker level which is couple of inches above the all too important rear port.

I thought of the time alignment issue too. But then reasoned that considering the distance between the speakers and my listening position is 7 ft (or 2.1m), the difference is 1.3/210 = just 0.16%. (The rear wall of the room is far behind, 12 ft behind my couch). Whatever time misalignment it might induce isn’t perceptible to me, while the improvement in tone and immediacy is.

but when using laser measure

What is this gadget? Can you provide a buying link? I’d be glad to use something easier than the two feet long steel ruler I use (placing it along its edge so it remains stiff).

 

[Phew]

Not so. The front wall (the one behind the speakers in my terminology) and my sitting (the couch) are perfectly parallel as evident from the flooring tiles. So the speakers are indeed 29,35 and 30.65 cm respectively from the front wall. I don’t measure at the skirting level, but at the top of the speaker level which is couple of inches above the all too important rear port.

I thought of the time alignment issue too. But then reasoned that considering the distance between the speakers and my listening position is 7 ft (or 2.1m), the difference is 1.3/210 = just 0.16%. (The rear wall of the room is far behind, 12 ft behind my couch). Whatever time misalignment it might induce isn’t perceptible to me, while the improvement in tone and immediacy is.



What is this gadget? Can you provide a buying link? I’d be glad to use something easier than the two feet long steel ruler I use (placing it along its edge so it remains stiff).

I use the skirting to measure distance between two walls not distance to speaker. Since you have measured and the walls parallel the possibility goes out the french window on the side .

Bosch GLM 500 professional for measuring distances and Bosch GLL 3-15 x 15 line laser level.

Drawing a straight line down the middle of the room front to back and then getting a perpendicular line to place the speakers. Doing so gives me two parallel lines one on which the speaker sits and one for the listening position, thats the starting point, post this I move the speakers front or back in mm's till I get the sound I like.

Since my PC is moved into the same room, I mostly listen to music with my back facing the speakers while working else just turn around and listen straight up.

This is how my room looks like. All doors are closed when listening to audio.

 

[arj]

The bosch is good I have ben using it for many years now.

Not so. The front wall (the one behind the speakers in my terminology) and my sitting (the couch) are perfectly parallel as evident from the flooring tiles. So the speakers are indeed 29,35 and 30.65 cm respectively from the front wall. I don’t measure at the skirting level, but at the top of the speaker level which is couple of inches above the all too important rear port.]

There could be other reasons than the wall also causing this..as long as your ear has got it right just trust it and adjust the seating position accordingly

 

[prem]

Not so. The front wall (the one behind the speakers in my terminology) and my sitting (the couch) are perfectly parallel as evident from the flooring tiles. So the speakers are indeed 29,35 and 30.65 cm respectively from the front wall. I don’t measure at the skirting level, but at the top of the speaker level which is couple of inches above the all too important rear port.

I thought of the time alignment issue too. But then reasoned that considering the distance between the speakers and my listening position is 7 ft (or 2.1m), the difference is 1.3/210 = just 0.16%. (The rear wall of the room is far behind, 12 ft behind my couch). Whatever time misalignment it might induce isn’t perceptible to me, while the improvement in tone and immediacy is.



What is this gadget? Can you provide a buying link? I’d be glad to use something easier than the two feet long steel ruler I use (placing it along its edge so it remains stiff).

Since you measure at the top of the speaker and your speaker is a stand mount, there is a possibility of a slight tilt of the speaker which might be reflecting in this 1.3 cm difference. Our floors are not perfectly flat. There is invariably a very minor tilt

As Arj said, go with what sounds good to your ears

 

[ajuvignesh]

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

John hunter recommends this method for speakers. Not sure of subwoofers.
In my case, I left my speakers equidistant from my ears and let the dirac live do the magic.

 

[arj]

Lots of folks have a similiar method. Other than Cardas and Wilsons, Audio-physic also had a similiar method I think..but in the end its all the starting point and then the hard work of figuring out the right point by ear.

 

[jmascreen]

How different is the master set way using jennifer warnes song as test?

 

[prem]

How different is the master set way using jennifer warnes song as test?

Use any song you want as long as you are familiar with it and understand tone and timbre

 

[alpha1]

Does this also mean that when you listen you ensure that the ear doesn't move even 5 mm ever?
No nodding of appreciation, no bobbing with the rhythm, no swaying of body, not even a minute eye movement (the head usually rotates unknowingly to assist the gaze - try doing it): so just plain lifeless statue then.

 

[sachinchavan 15865]

Since you measure at the top of the speaker and your speaker is a stand mount, there is a possibility of a slight tilt of the speaker which might be reflecting in this 1.3 cm difference. Our floors are not perfectly flat. There is invariably a very minor tilt

Possible. I’ve never checked with a level gauge. Let me get one.

Does this also mean that when you listen you ensure that the ear doesn't move even 5 mm ever?
No nodding of appreciation, no bobbing with the rhythm, no swaying of body, not even a minute eye movement (the head usually rotates unknowingly to assist the gaze - try doing it): so just plain lifeless statue then

My experience with my system is, while the position of the center image moves as I move laterally (not as little as nodding the head sideways, but actually shifting from one sofa seat to another, the tone or clarity doesn’t. I sit in the center for intent listening only because I like the image right in front of me (as well as the entire span of soundstage as possible). But even when I sit in the sofas on one side or another at other times, the tonality doesn’t change.

There could be other reasons than the wall also causing this..as long as your ear has got it right just trust it and adjust the seating position accordingly

What could be the other reasons? I shall check for the tilt as suggested by Prem.

As for adjusting the seating position, many of us in cities like Mumbai don’t have much leeway to rearrange our furniture. I’ve decided long back that the audio won’t dictate the living room arrangement, but will have to adjust with it.

 

[arj]

Not at all. its the speaker position which is critical.

Does this also mean that when you listen you ensure that the ear doesn't move even 5 mm ever?
No nodding of appreciation, no bobbing with the rhythm, no swaying of body, not even a minute eye movement (the head usually rotates unknowingly to assist the gaze - try doing it): so just plain lifeless statue then.

you will get a similiar tone ( not the Imaging) anywhere..even in the next room when it is right..it is the sound origin which is important to lock in not the ear position. If the other were the case everyone in the room would hear a very different sound which does not make sense,

What could be the other reasons? I shall check for the tilt as suggested by Prem.

As for adjusting the seating position, many of us in cities like Mumbai don’t have much leeway to rearrange our furniture. I’ve decided long back that the audio won’t dictate the living room arrangement, but will have to adjust with it.

anything affecting sound.in my case it was the rack. On seating position I meant tilting the chair at the angle to bring it to the center thats all

 

[reignofchaos]

Does this also mean that when you listen you ensure that the ear doesn't move even 5 mm ever?
No nodding of appreciation, no bobbing with the rhythm, no swaying of body, not even a minute eye movement (the head usually rotates unknowingly to assist the gaze - try doing it): so just plain lifeless statue then.

Tone and Timber doesn't depend upon the listening position significantly in this case assuming you are sitting around in the same spot. The speaker position decided how it interacts with the room. This doesn't hold for extreme cases obviously.

 

[jenson]

As for adjusting the seating position, many of us in cities like Mumbai don’t have much leeway to rearrange our furniture. I’ve decided long back that the audio won’t dictate the living room arrangement, but will have to adjust with it.

curious, is the back wall right behind listening position...at least 1-2 feet gap is advised, if not more..

as far as i understand, Placing the listening area such that the walls with the French windows serve as the front wall can be a good idea. In this setup, opening the French windows can indeed help minimize back wall reflections and seating area would have back wall placed much farther...safe to assume all these deliberations were made and it may not be aesthetically possible...

 

[sachinchavan 15865]

curious, is the back wall right behind listening position...at least 1-2 feet gap is advised, if not more..

@jenson, there’s a lot of space (9 feet, I wrongly typed 12 feet earlier) between the listening position and the rear wall.

safe to assume all these deliberations were made and it may not be aesthetically possible...

Yes. Not worth compromising the natural/intended arrangement of the living (cum dining) room. Audio is just one part of ‘living’.

 

[jenson]

@jenson, there’s a lot of space (9 feet, I wrongly typed 12 feet earlier) between the listening position and the rear wall.

that's awesome

Audio is just one part of ‘living’.

as it should be, but then...

 

[prem]

This is in response to a few queries I got on mail.

At the right position, voices will not sound bright or hard. In any decent system, at the correct position, the emotion and flow will come through. If the voice is a bit hard, the flow will get cut. It’s very easy to mistake brightness for treble. If the treble is correct, voices will be soft and not hard and the attack will improve. Cutting of treble will make voices hard.

At the right position, you might initially get the feeling of loss of excitement. I remember Arj initially reacting to the new position That’s understandable because an exaggeration in a certain frequency band always adds excitement. When you remove this exaggeration, the initial impression is that of losing the excitement.

4-5 cm ahead of the correct position, you’ll find the sound impressive but that’s because there is a certain bloat which makes everything sound a bit bigger. At this position you’ll lose solidity in the bass. Arj has experienced this too.

 

[arj]

I remember Arj initially reacting to the new position That’s understandable because an exaggeration in a certain frequency band always adds excitement. When you remove this exaggeration, the initial impression is that of losing the excitement.

4-5 cm ahead of the correct position, you’ll find the sound impressive but that’s because there is a certain bloat which makes everything sound a bit bigger. At this position you’ll lose solidity in the bass. Arj has experienced this too.

So treu for a very long time the placement position i got was this space where the sound was "exciting" around 2.1m ..moving to the position behind by little less than 5cm and the excitement ie tight bass ( which was actually sounding because it was cut) and sharp midrange ( the bass was riding on it) became more balanced.

 

[Analogous]

So treu for a very long time the placement position i got was this space where the sound was "exciting" around 2.1m ..moving to the position behind by little less than 5cm and the excitement ie tight bass ( which was actually sounding because it was cut) and sharp midrange ( the bass was riding on it) became more balanced.

Reading all this @arj i am coming over soon to experience it first hand!
Missed @prem ’s master class in speaker placement when he was in town this time but hopefully Prem you will be back soon?