Are room acoustics a factor in near-field listening?

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clave

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Hi.  I'm trying to determine the cause of a bit of midrange glare in my system.  If I'm hearing it (though reduced) when listening near field does that suggest it is caused by electronics or speakers as opposed to the room?  Or do reflections, reverbs and the like still have an effect even when sitting closer to the speakers than the speakers are to the walls?  Thanks for any insight you can offer.

Bob2

Re: Are room acoustics a factor in near-field listening?
« Reply #1 on: 19 May 2017, 01:26 am »
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G Georgopoulos

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Re: Are room acoustics a factor in near-field listening?
« Reply #2 on: 19 May 2017, 01:34 am »
Could be both,distrortion of electronics or reflections in the room

JLM

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Re: Are room acoustics a factor in near-field listening?
« Reply #3 on: 19 May 2017, 01:47 am »
If this is a carefully controlled experiment, I'd say yes.

In general near-field setup should reduce room effects.

zoom25

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Re: Are room acoustics a factor in near-field listening?
« Reply #4 on: 19 May 2017, 02:01 am »
Posting a picture of the setup, room, and gear would help diagnose things.

Mag

Re: Are room acoustics a factor in near-field listening?
« Reply #5 on: 19 May 2017, 02:18 am »
I recall the staff room of the casino I use to work, how your voice echoed off the walls made speech more difficult to discern. So yeah the room is a factor.

The room I use for audio, initially I thought it was a bad room because the bass was boomy. Turns out it was just a cheap sub because when I bought a better sub it sounded like a sonic boom in comparison.

I noticed one day when an airplane was coming is for a landing at the local airport. I could not hear the airplane approach, then when it got closer I could hear the airplane reflect off the brick building behind me, it was so clean, clear and loud, no hint of distortion.

So realizing I could use reflections, I aimed my tower speakers to reflect off the back concrete wall about 3' left and right of my listening chair and I get beautiful imaging off the front wall that is like 12' x 8' like a large movie screen only it's sound projecting off the wall.

IMO if you do the slap echo test and you hear no echo the room is good. Boomy bass and possibly mid-range  glare I would associate with either the equipment or the speaker not being able to produce a recorded sound cleanly. :smoke:

clave

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Re: Are room acoustics a factor in near-field listening?
« Reply #6 on: 19 May 2017, 02:50 am »
Posting a picture of the setup, room, and gear would help diagnose things.

True, but odd as it may sound, right now I'm not trying to fix the problem, which is pretty subtle by most standards. I was mainly curious as to whether room boundaries influence the sound when sitting closer to the speakers than the speakers are to the walls.

JLM

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Re: Are room acoustics a factor in near-field listening?
« Reply #7 on: 19 May 2017, 09:29 am »
The music reproduction system includes the room (after speakers, the most important factor IMO). 

If you really want to listen to just your source, amps, and speakers move to the top of a tower in a windless desert.  Short of that, yes near-field is the best way to easily reduce room effects.  It produces a more smaller but more active presentation where imaging snap into place when sitting in the "magic" listening position, similar to a blend of headphone use and "far-field" (conventional home audio) setup.  Note that there is no definition of near-field.  I started by following Cardas recommendations (in my case a 70 inch equilateral triangle) and experimented from there. 

If you'd like to learn about in-room acoustics a good resource is Floyd Toole's book entitled "Sound Reproduction".  Toole doesn't get excessively caught up on room contributions of mid/treble frequencies in a common sense set up.  In his opinion we're all conditioned to hearing in rooms, so the brain sorts out most of the disagreeable room effects.  But of course the room does add colorations, thus the market for room treatments (most of which are all but useless).  Note that treatments are bandaids for less than ideal rooms.  I have six GIK 244 panels that do almost no good in my room but have worked wonders elsewhere.

A couple of basic pieces of advice:  Avoid highly reflective surfaces at first side/front wall reflection points (where if you put a mirror there you'd see each speaker from your listening spot).  Bass collects at wall/wall, wall/floor, and wall/ceiling intersections so put bass absorption there if you want to reduce bass boom.  Avoid cubic shaped rooms or rooms that primary room dimensions (height, width, length) are in 1:2 ratios.  Odd shaped (non-rectangular) rooms are the least understood and the hardest to predict how they'd sound or treat.  Bass is best reproduced from multiple sources (subwoofers) located around the room after much setup experimentation.

IMO outside noises are worse.  So your listening room should be acoustically isolated/insulated.  It allows you to listen more quietly as background noise is reduced and to listen without bothering others (currently listening at 5AM without disturbing wife/stepson).  My room is in the basement (no windows), has an insulated exterior fiberglass door with weatherstripping and flexible/lined fiberglass insulated ductwork so I can barely hear the furnace.  It's primary dimensions follow the golden ratio (fabiano ratio) of 8ft x 13ft x 21ft to minimize standing bass wave echoes.  Toole list a range of acceptable ratios.

dhrab

Re: Are room acoustics a factor in near-field listening?
« Reply #8 on: 19 May 2017, 11:04 am »
Ya might give this a try ... put on a track where the glare is very evident and sit in the sweet spot and confirm glare is present ... then repeat the same track immediately but go into an adjoining room ... next to the listening room and listen

If the glare is greatly reduced ... it's a room issue as listening in the adjoining room takes you out of the direct reverberant field that is causing the glare ... if the glare is still very prominate while listening in the next room over ... it may be power or equipment related issues

One day while listening to Rachel Farrell .. who can be very punishing and revealing of room and equipment short comings ... I went upstairs to the kitchen for something to drink ... after pouring a glass of cold water ... while listening from the upstairs kitchen ... I heard most of the irritating anomalies were gone pointing to the room as the problem ... measures have been taken and things sound much better now

first try to establish if it's the room or the equipment and then measures can be taken

jimtranr

Re: Are room acoustics a factor in near-field listening?
« Reply #9 on: 19 May 2017, 03:54 pm »
Room acoustics are a factor and midrange glare an issue in my shared-space secondary-system 11'x13'x7'8" bedroom, where room size, furniture placement,  foot-traffic patterns, and--above all--the need to maintain domestic peace and tranquility virtually mandate nearfield listening. In that particular environment, treating the room (with GIK 244s, 224s, and Monsters) eliminated the glare.

Had the same midrange-glare experience a few years ago listening in a friend's apartment's postage-stamp-sized second bedroom that was populated with just his system components and a couple of nearfield chairs. I hauled in four ASC Tube Traps, setting one each at the front corners and the first reflection point on either side wall--and killed most of the glare. If I could have stuffed more traps in my car, I'd have also treated, at minimum, the center of both the front and rear walls, given their reflective contribution to the overall sonic picture.

Offered as descriptive of my experience in two situations and not as prescriptive, as individual listening environments vary. 

mick wolfe

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Re: Are room acoustics a factor in near-field listening?
« Reply #10 on: 19 May 2017, 04:45 pm »
Yep, pretty much mirrors my experience.  My small room system pretty much dictates a near field set-up. The difference after adding room treatments was significant to say the least. Went from a somewhat fatiguing listening experience to a much more pleasant and listenable presentation. Used the basic approach of absorbing panels on the front and side walls/diffusing panels on the back wall. Every bit as significant as adding an upgraded component, cable, etc.

OzarkTom

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Re: Are room acoustics a factor in near-field listening?
« Reply #11 on: 19 May 2017, 05:09 pm »
After midnight, does the glare reduce? If so, it could be AC glare from the electronics.

jk@home

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Re: Are room acoustics a factor in near-field listening?
« Reply #12 on: 19 May 2017, 11:26 pm »
No matter what, you still should set up a reflection free zone, either attenuate the reflected sound, or time delay it via diffusion. This site has some good info:

http://arqen.com/acoustics-101/reflection-free-zone/

Another trick that helped in my system was tilting the speakers (KEF LS50s) back 6 degrees. Since the listening position is at a desk, this aimed more energy away from the floor and the lower portion of the desk.




 

JWL.GIK

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Re: Are room acoustics a factor in near-field listening?
« Reply #13 on: 25 May 2017, 06:13 pm »
Yes, room acoustics are definitely a factor in near field monitoring setups. Most likely the midrange glare will be helped a lot by early reflection management and bass trapping (which can then unmask other problems and change your perception of midrange).

DaveC113

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Re: Are room acoustics a factor in near-field listening?
« Reply #14 on: 25 May 2017, 06:47 pm »
Yes, room acoustics are definitely a factor in near field monitoring setups. Most likely the midrange glare will be helped a lot by early reflection management and bass trapping (which can then unmask other problems and change your perception of midrange).

I agree, early reflections are a good possibility, longer reflections not as much.

Also see if the glare decreases or goes away at low volumes and increases as SPLs increase. If glare increases with volume it's more likely to be a room issue, but many drivers also produce more artifacts at higher SPLs too, although I wouldn't say it sounds like glare unless you have ribbon tweeters. If it's evident at low SPL then it's more likely an issue with power, electronics or cables. Glare is commonly produced by dirty AC power or cables with lesser purity (4N or lower) silver, silver plated wires or lower quality connectors, especially if rhodium plated brass.

Folsom

Re: Are room acoustics a factor in near-field listening?
« Reply #15 on: 25 May 2017, 08:05 pm »
R/L balance is maybe the most challenging. It's very sensitive to distance to the wall behind it, and variations around them. You may not end up with symmetrical placement for proper balance.

The reflections are not helpful, but not the worst thing ever. It would still be good to reduce them, like always. They are more prone to blurring than characteristics that are "bad", like some offensive bit; at least in this type of setting. If you crank it up to 110db average in a night club, then all bets are off for what is coming back in a terrible way.

The bass loading means the distance from the walls can be awkward to, as loading in the wrong range is bad, and may leave the bass sounding a bit weaker.

Folsom

Re: Are room acoustics a factor in near-field listening?
« Reply #16 on: 25 May 2017, 08:26 pm »
It may have nothing to do with the room, too. Could be ringing on the driver, etc.