Near or Far what type listener are you?

[prerich]

Simple poll to see how many people primarily listen in the nearfield vs the farfield.

 

[flipflop]

Everyone should be listening in the far-field.

Figure 10.9 shows the situation for point sources and combinations of “point-like” sources: loudspeaker drivers in a box.
Figure10.9a shows an ideal point source radiating sound equally in all directions in free space. The sound energy is distributed uniformly over a spherical surface that, as a function of distance, experiences a rapid increase in area over which the sound energy is distributed. The sound energy per unit area (called sound intensity) is inversely proportional to the square of the distance from the source, so this relationship has come to be called the “inverse-square law.” The sound level correspondingly falls rapidly, at a rate of −6 dB/double-distance).
With an ideal point source this relation holds for any distance. However, practical sound sources are not infinitely small points. When sound radiates from a complex source like a loudspeaker or large musical instruments, what is measured and heard at different frequencies is different at short distances and long distances. In the near field, as shown in Figure10.9b, the sound level at any frequency is uncertain. Figure10.9c shows estimated distances at which far-field conditions should prevail for a loudspeaker system and for its components. This would be the minimum distance at which a microphone should be placed for measurements, and at which listeners should sit in order to have a predictable experience.
Beranek (1986) suggests that the far field begins at a distance of 3 to 10 times the largest dimension of the sound source. At this distance the source is small compared to the distance, and a second criterion is normally satisfied: distance^2=wavelength^2/36.

 

[Deleted member 21219]

Everyone should be listening in the far-field.

View attachment 297059

Siemens DISW

Long ago, I was told the rough (perhaps too rough) method for figuring acoustic nearfield, midfield and farfield in enclosed spaces (not free field).

Nearfield:
The transducer is closer to your ears than it is to any boundary, and your ears are closer to the transducer than they are to any boundary. This means, simplistically perhaps, that the direct emission from the transducer arrives sooner than any reflection and is apparently stronger than any reflection or set of reflections.

Midfield:
The area between you and the transducer contains enough reflecting surfaces that the reflected field will affect the apparent balance of the transducer. This is our normal listening environment; same speaker in different rooms will sound different because of the different acoustics in those rooms. Additive and subtractive interference in the bass can change the apparent balance between bass and midrange.

Farfield:
The acoustic environment (and its native reflections) is so strong that it can modify the apparent direct signal from the transducer. Arenas, transportation terminals and auditoriums are examples of farfield environments; speech clarity (especially) can be a problem in the farfield.

Freefield:
The listener is in an environment where reflections have no apparent contribution to the sound.

In all these (very old) definitions, the important qualifier is the apparent (or obvious) balance of the direct-versus-reflected sound field, and its ability of reflections to interfere with the original signal.

Hope this was not too dinosaur for you.

Jim

 

[dualazmak]

....
....
In all these (very old) definitions, the important qualifier is the apparent (or obvious) balance of the direct-versus-reflected sound field, and its ability of reflections to interfere with the original signal.

Thank you for your fundamental and educational notice! I fully agree with you; I (we) always need to find proper and/or preferable "compromise and balance" of the direct-vs-reflected in our home audio listening setups.

My setup including the rooms is really typical "Midfield" with asymmetrical room/furniture where I could find the nice/acceptable "compromise and balance" as shared here and here.

 

[fpitas]

Barely farfield, about 9ft away.

Speakers are about 9ft apart.

 

[NTK]

The technically correct terms are direct field listening vs reverberant field listening, not near field vs far field.

http://www.sengpielaudio.com/DirectFieldAndReverberantField.pdf

 

[MattHooper]

Speakers 8 feet apart, listening position between 6.10' to 7.1' from speakers.

You tell me

 

[flipflop]

The technically correct terms are direct field listening vs reverberant field listening, not near field vs far field.
http://www.sengpielaudio.com/DirectFieldAndReverberantField.pdf

All 4 terms are correct as the sengpielaudio document explains. The only questionable term used in this thread is "midfield".

 

[Hexspa]

Curvature recently posted an AES paper which put listeners 2/3 the distance (length?) which they identified as the 'critical distance' which is the point where the direct and reflected sound is equal. To me it makes sense that nearfield is closer than this, far field is further than this and midfield is probably right around here. The amroc calculator gives estimates for critical distance. In a small room, this is around 1m assuming a nominal amount of absorption (I don't know exactly how they're coming up with this number).

If we define far field as 'reverberant field' then small rooms have no far field because they don't really have reverb. Reverb is equal energy at all directions and that doesn't happen in small rooms afaik so let's define near-mid-far in terms of relative strength of reflections to direct and not what kind of reflections they are since that will depend on the room.

 

[IAtaman]

Near, far, wherever you are, I believe that the heart does go on.

 

[Sal1950]

I think of nearfield listening as the computer desktop listener.
This is where the listener is sitting at a desktop with a couple mini-monitors either on the edges
of the desk or mounted just outside and behind it. Very similar or the same as many mixing console
arrangements, that are mostly eliminating room sound/reverberation from the listener.

Midfield has the speakers in the classic arrangement with the speakers out from the rear/side walls
3-5 feet and somewhere close to the equilateral triangle with speakers&mlp 6-10' apart.

Farfield basically the same as midfield but adjusted for very large room sizes.

 

[prerich]

I would guess that you meant "nearfield vs. midfield", not farfield, but I could be wrong.

Jim

I started to add a Midfield choice - but for the sake of the poll - count midfield as farfield.
Midfield is 5 to 10 feet, I actually listen in the beginning of the farfield (11 ft away from my mains)

 

[prerich]

Oh fyi my speakers are 8 feet apart, 4 feet from the wall behind them, 3 feet from the side walls, and 11 feet from the listening position.

 

[Deleted member 21219]

I started to add a Midfield choice - but for the sake of the poll - count midfield as farfield.
Midfield is 5 to 10 feet, I actually listen in the beginning of the farfield (11 ft away from my mains)

Looking at the replies given by other posters, I can see that I didn't quite get my meaning across clearly.
If we make assumptions about the acoustic makeup of common rooms, then I can somewhat understand the replies that quote distances, but nearfield, midfield and farfield do not necessarily depend on distance for their definitions.

Imagine yourself in an perfect anechoic chamber. This chamber would have no reflections, so it would have no reverberant field and therefore no interference. As long as the signal from a multi-way system integrated properly, you could sit 2 feet away from the speakers, or 8 feet away, or 15 feet away, and to your ears, there would be no difference except SPL. The acoustic description of the sound field would be "nearfield", because in all cases, the dominant and overriding signal would be the direct signal from the transducers.

As an extreme opposite example, try listening to a professional nearfield monitor at close range (let's say something like 3 feet) in a concrete culvert 6 feet in diameter. The sound is totally ruined by reflection from the sides of the culvert. Even if you moved closer than 3 feet, it wouldn't help; the dominant characteristics to the sound would be from the reflections in the culvert.

I know that both of these examples are extreme, but they illustrate the point that nearfield, midfield and farfield are, at their core, definitions of acoustic characteristics, and therefore depend on the acoustic environment, not simply arbitrary distances.

Jim

 

[prerich]

Looking at the replies given by other posters, I can see that I didn't quite get my meaning across clearly.
If we make assumptions about the acoustic makeup of common rooms, then I can somewhat understand the replies that quote distances, but nearfield, midfield and farfield do not necessarily depend on distance for their definitions.

Imagine yourself in an perfect anechoic chamber. This chamber would have no reflections, so it would have no reverberant field and therefore no interference. As long as the signal from a multi-way system integrated properly, you could sit 2 feet away from the speakers, or 8 feet away, or 15 feet away, and to your ears, there would be no difference except SPL. The acoustic description of the sound field would be "nearfield", because in all cases, the dominant and overriding signal would be the direct signal from the transducers.

As an extreme opposite example, try listening to a professional nearfield monitor at close range (let's say something like 3 feet) in a concrete culvert 6 feet in diameter. The sound is totally ruined by reflection from the sides of the culvert. Even if you moved closer than 3 feet, it wouldn't help; the dominant characteristics to the sound would be from the reflections in the culvert.

I know that both of these examples are extreme, but they illustrate the point that nearfield, midfield and farfield are, at their core, definitions of acoustic characteristics, and therefore depend on the acoustic environment, not simply arbitrary distances.

Jim

I understand what you are saying in this post, good post as well!