Understanding nearfield separation & bass

Hi,

So I'm trying to figure out the best way to build speakers for music and gaming, my computer monitor is as wide as my desk and so the speakers will have to go just above the monitor angled down a bit.

For nearfield, I'll be less than 1m away, how much stereo separation would I need, is 1m sufficient?

I would like punchy explosion and gun fire effects, what size of woofers would I be looking at, ideally the speakers wouldn't be too unwieldy?

I'm thinking that if there was separate HF (for this application maybe I don't care much about over 4KHz?) that you would want to be very near the woofer or even coaxial?

I could maybe have some sub bass behind the desk.

How would you approach it?

Thanks!
 
Near field is purposeful……you’ll get the direct sound without any smearing from first reflections other than the desktop and your monitor. You don’t have to concern yourself with direct sound bass…..the wavelengths are far too long to matter in the near field.

The other advantage of near field is you don’t have to worry about off axis response……EVERYTHING will be on axis…..so the on axis driver response is your target. A well behaved full range or wide range driver excels here along with coincident/coaxial drivers. AVOID anything with a wizzer cone though…..you can hear the distinct breakup of these when your at 30”

IMO as a long time recording engineer for enjoyable listening in this scenario?………a good pair of open back headphones combined with a bass/midbass woofer behind your monitor facing the wall. This combination still connects you to the space of you run the midwoofer up to 1khz or so. If you’re using your desktop computer as your source, you can delay the signal sent to headphones a little to avoid the time smear. This is an ambient approach and works better than anything I’ve ever experienced for near field enjoyment when you can’t separate the left and right channels by more than the listening distance.
 
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The other advantage of near field is you don’t have to worry about off axis response……EVERYTHING will be on axis…..so the on axis driver response is your target.

That only applies if you don't move. With less than 1m listening distance you can get quickly in the range where the off-axis dispersion changes the sound a lot. Not only if you move from side to side but also back / front. So the off axis response is still important.

The dispersion should still be controlled because you forgot the short reflections of the desk - which can be a worse than the room reflections because they muddy the location often even more.
 
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I wasn't even aware of an equilateral triangle rule, thanks!
It's a rule of thumb, a starting point. Practically all speakers will have decent to good stereo separation with that positioning.

However as I said it is a starting point, different speakers behave differently when you stray from that theoretical ideal.

In my experience with Tannoys co-axial drivers are more forgiving of a positioning which would usually be deemed to be too wide.


If you want to get them as far apart as possible sit in your normal place and move the speakers further apart gradually.
At some point you should notice a central 'hole' in the stereo field. At that point you will need to move the speakers closer together again until that 'hole' disappears and you get a smooth stereo image. A little bit narrower really.
 
@ICG from my reply

“you’ll get the direct sound without any smearing from first reflections other than the desktop and your monitor.”

I work in the near field 6-8 hours a day so I’ve heard a thing or two

And yet you claimed the off-axis wasn't any relevant. Listening to the same for 6-8h a day makes you very numb to that sound (and the flaws) as you accepted this as to be normal. Someone who regularly listens to different speakers is a lot more capable of registering faults in the reproduction of the sound. You can mix reliable on your speakers, I'm pretty sure about that but you expect the same sound (and characteristics and flaws of it) from other speakers too. I'm not even going into the room characteristics but it's clear you are setting your listing environment as standard - which obviously doesn't apply to @rthorntn to that extent. I don't doubt you can judge the sound of tracks on your setup but I doubt it is very helpful to the thread starter. Long time experience on one specific thing is not always helpful on other circumstances.
 
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Thanks everyone!

a good pair of open back headphones combined with a bass/midbass woofer behind your monitor facing the wall

This is an amazing suggestion, thanks!

run the midwoofer up to 1khz or so

Could you expand on this, a midwoofer or a woofer, what size, wouldn't I want to get as close as possible to 30Hz, maybe an array behind the monitor (for depth reasons)? I found a chart here that I think says I would need to move 3.2 cubic inches of air, so that's roughly 50000 cubic mm, so a woofer with an area of 5000mm and 10mm excursion?

I have a 12" 32mm excursion and four 6.5" 3mm excursion woofers in my "inventory". It'd have to be a very shallow box, so all the volume would have to come from the width and height.
 
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High quality studio headphones are typically near flat to below 20hz…….no need to add anything there…..you just need to better couple the room, headphones and your ears into the soundstage.

Why did you propose to let these woofers play up to (very well noticeable direction & location obvious) 1k? Room coupling doesn't happen above max 200Hz.
 
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Thanks everyone!



This is an amazing suggestion, thanks!



Could you expand on this, a midwoofer or a woofer, what size, wouldn't I want to get as close as possible to 30Hz, maybe an array behind the monitor (for depth reasons)? I found a chart here that I think says I would need to move 3.2 cubic inches of air, so that's roughly 50000 cubic mm, so a woofer with an area of 5000mm and 10mm excursion?

I have a 12" 32mm excursion and four 6.5" 3mm excursion woofers in my "inventory". It'd have to be a very shallow box, so all the volume would have to come from the width and height.

I have tried to combine open-back headphones with external woofer/subwoofers, and achieving coherence and naturalness is VERY difficult. If you already have them, try it, but good headphones (doesn't have to be open) plus a bass shaker screwed to the bottom of your seat is another idea. Heck, even if going with desktop speakers..

Something like this:
https://www.amazon.com/Dayton-Audio...=se&keywords=buttkicker&qid=1728267556&sr=8-3
 
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The coherence problem is really difficult, especially impossible if the bass goes up to 1k.

I had the same idea about the bass shaker. Great idea but the fact you're running over the wires with the chair makes it a no-go in practice. It's a close to perfect choice though if the chair will not be moved, it reduces the noise vastly while making the feeling more realistic than just by sound.
 
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My crazy-fidelity desktop 15in reflector-coaxial wide-dispersion point-source "Axia". Easiest to go semi-nude with sub under desk.

(description)

(recording)
 
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