Treatise On Near / Far Field Listening

Something I've never seen. All I know about it is small speakers produce a desk / table size near-field. I'm going to assume that the listening experience in the near-field at a desk is -

- better than headphones, but similar.
- worse than far-field.

So let's imagine a recording desk with smaller (say, 4") near-field monitors placed in the usual spot (at the back of the desk...). Say you happen to have plenty of space behind the desk for all the image depth you'd ever want. Then someone suggests bringing out the Urei time-aligns (say, 12") to see what they do. Where would you put them to envelope those listening in the near-field?

I'm imagining smaller speakers cast a smaller near-field shape / dimension and larger ones... But I've never seen this explained in the context of choosing your speakers to fit the space you have, for a near-field listening experience.
 
It should be pretty easy to sort out, and just because I havent seen it explained... Something like;

1. Do you want to listen in the near field or far field? "I want near field"
2. What's your listening space and where are you in it? "I'm at a desk in front of my PC display"
3. Ans: A pair of these Fostex FE103en models in small cabs should do for a FR solution.

Now change the space part to "I'm on a sofa 10' back from the speakers". Ans: Got room for Altec A7s? So assuming for the moment that answer is basically correct, my question is simply "why" and "how does it work"?

If the correct answer is no speaker (or array) of any dimensions will have you in the near-field at that distance, I'd like to know the same, "why" and "how does it work" i.e. near-field is near-field and that's an absolute having to do with some immutable constant in physics, like the speed of sound, the average size of a person's head, etc.

Thanks!
 
Last edited:

PRR

Member
Paid Member
2003-06-12 7:04 pm
Maine USA
www.diyaudio.com
> the actual distance will be room dependant.

Yes, but not very. Typical critical distances will be 4 feet in a livingroom and 13 feet in a 1,000 seat concert hall. (I used to find Dc for pay.) There's usually no doubt if your room is nearer 4 or nearer 13.

For rooms that are not-hard and not-dead, 1/4 of the average length width height is probably right. So my 12'x24'x9' room with huge furry dog in corner estimates as 3.5' which is indeed about what I observe. Then a fairly-near distance is 1.8', which is arm-length, and indeed my PC monitors are just in the "near" field.

In a 5'x10' closet, raw Dc under 2', I had to hang a lot of foam and carpet to get Dc out far enough to listen "near" the speakers and still have desk-space for notes. Even then I used headphones to judge "sound stage".