How to diagnose the need for room treatment?

I can't tell from your comments exactly how much actual speaker/sitting positioning work you have already done, or how you did it, so it is really hard to comment on what you should do next.

BUT, IMHO, you really can't get your sound to 'improve' until you can describe specifically what it is that you expect to improve by making any changes or use of 'room treatments'.

FWIW, it strikes me from your comment 'it sounds good to me' that you really haven't a focus on exactly what to expect, just that you think by adding something it might get better, when actually it not only might not, it might sound worse.

Based on that assumption, I would suggest that you save your money for a while and try to improve the sounds in your room (assuming you are not restricted by WAF) simply by carefully tweeking placement/toe/listening chair positiong until your set up produces tonal smoothness from bass thru highs (you can use a SPL meter and a disc with test tones) and clarity of tone, a set up which produces this clarity in the context of a soundstage which is wide and deep (and if possible, but it is more equipment dependent, high).

Room treatments are good when you have identified specific problems in identified frequencies and select the treatments that are designed to do it. There is no 'one size fits all' solutions, and some things are unobtainable at any realistic price or visual acceptance to many.

FWIW, I've been able to set up a modest sized room with fairly flat/smooth frequency response +/- about 3db except for a 5db boost at 32hz (not tameable) and a 40/50 hz 5db suckout (room dimension created and not tameable either) without using any acoustic materiels other than normal domestic furnishings. It only took a couple of years to do it all. Lots of small changes and patient listening to speaker/listening seat tweaking. :-)

If you want some down and dirty recommendations, I would suggest that you post your rooms dimensions, identify present locations of speakers and listening chair, along with a description of and location of room openings (windows and doors), and stuff placed on/near walls.

Also a description of your equipment, especially your speakers, and if possible what you would like to improve, sonically.

Fundmentally I agree with Sbank - I would only like to reinforce the fact that speaker/room set up, assuming you have already done some of the preliminary work, and if you have high expectations, is not a short term project with quick fixes. It is a slow methodical process with a lot of small changes and patient listening.

Hope that helps a bit.........

FWIW, in my post I referred to 'smooth FR' but I purposefully did not say 'flat FR'. Flat suggests to me hearing all frequencies at the same SPL, and when I have heard sounds in a room that were measurable as flat (especially from speakers which allegedly had a flat FR) the result was too much upper-mid and high frequency energy, where as a 'smooth' albeit tilted FR could be much more realistic for most installations.

Personally I really detest peaky mid-range and upper midrange FR, and it is easy thru measurements to determine whether this is attributibutibe to the speaker or the room (or both) by doing both near field and listen position measurements. Am I wrong, or am I missing the point?

SPL meter readings could be a LOT worse - a few observations.....

1)5db bump at 32 hz will add just a little sense of deep bottom end, not a bad thing actually for many.
2)3.5 db boots at 85db will add to the sense of bass, again not a bad thing, and the 2.0 db boost at 60hz will reinforce it. BUT...

3)Then you have a broad gently dip in the upper bass, lower midrange. Not a bad thing in itself, but might serve to over emphasize the appearance of the 'boosted' bass, and make it sound heavier than it actuall is.

4) After a normal 1 1/3d octave centering at 1000hz you have a broad and very audible dip in the mid/upper mid/highsrange which is going to make your speakers very 'forgiving', especially when using digital sources, but many might think the sound is dullish.

5)most speajers display the sharp roll off in the highs abouve 10K. I think mostly because you are comparing your 'in room specs' with anechoic measurements made by the manufacturer either 1 or 2 meters from the speakers.

I agree with Sbank about the effect of speaker placement, but what I think of when I see your comments about listening distance from speaker to speaker and speaker to listening chair, is not so much making a major correction to the SPL levels you mentioned because I don't see that so much a big deal. Some changes might be made in the bass, but the broad nature of the dips in the mids and highs suggest to me that the speakers are the cause, or the room surfaces are over damped.

What I do think you can do (if your wife and situation allows) is to get some space between your speakers. For example, I typically listen to dynamic speakers that are about one foot+/- closer together than they are apart. In your case that would be about 10 feet. If you thin that they are too close to the side walls you can simply try toeing the speaker in towards your seat, even substantially past it, to control 1st sidewall reflections. What you should get by doing this is getting a vastly improved since of sound stage in all dimensions.

FWIW.

Shadrone/Almarg - Good point about beaming in HF and the effect of tinkering with toe-in. But with speakers 11 ft away, and with only a six ft spread, you really are not that far off axis to begin with.

Shadrone, "The bass response is superb...". Obviously I agree, but let me say that I never thought it was suspicious. It actually resembled my bass frequencies before I tweeked the set up a bit (without using any acoustic crutches, which I still do not need). For fun, and for illustration of the benefits of position tweaking for Lewinskih.

My set up is as follows, in a 13.5x19.5x9 ft room with the speakers 58" from the wall behind them, 9' apart and the listening spot (ear location) at either 52" or 36" from the back wall.

........52"....36"
1000 0db db0
200hz 0db 0 db
160 -1db 0 db
125 +2db +3db
100 +1db -2db
80 0db -2db
60 -2db -1db
50 -5db -4db
40 -4db -3db
32 +1db +4db

One might think that the bass response at 36 inches would be better because it is smoother and it has some beneficial (I think) boost at 32hz, like the poster. But to my ears, any linearity one might loose, the gain in imaging by moving the listening position forward 16 inches was huge.

Shadrone, I want to thank you for bringing to my attention something (some time ago in another post) about the creation of a null on the center line of the room. I've since moved my listening position and speakers off center line and it has helped in getting a more balanced frequency response whereas nulls had previously been a problem.

IMHO, of course, just a mid-day stream of (un)consciousness. :-)

Re distance - 10 ft from the plane of the speakers (10 1/2' from each speaker itself).

Re takaways - IMHO, yes.