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Lack of bass

120.153.248.1

I have just moved into a new house and am finding that my system is producing very little bass. It seems like the bass drivers aren't doing much. I have checked them and they are working.
The front wall (the wall in front of the listener and behind the speakers) has floor to ceiling glass doors which cover the entire wall aside from a width of 1 foot on each end. There is also a window on the left wall about a foot from the front wall. I have read that speakers need room reinforcement to produce adequate bass. Is it possible that the lack of wall behind and to the side of the speakers is causing the problem?
BTW the speakers are B&W 802N and the front face of the speakers are 5 feet from the front wall. I had these speakers 5 feet from the front wall in the old house and had much more bass. However, the old room had a double brick construction and whist there was a window on the front wall it was no where near as big as the glass doors I have now.

Follow Ups:

RE: Lack of bass - hifi1959 13:17:58 12/02/12 (0)
I experienced the same "Lack Of Bass" in a room I moved into with a pair of bass rich speakers. It turned out, for me, the bass was there the entire time. It was alot of other problems that got in the way. The most obviouse issue was upper mid and high frequency ringing that did not allow me to advance the volume much before my ears became fatigued. Through simple and cheap experments addressing reflections I knocked it way down and frequency response leveled quickly. Since then I have startigic placed absorbers on walls and bass traps in three of the four corners of my room. System is sounding nice and I can fine tune now.
RE: Lack of bass - David Aiken 14:10:19 08/01/10 (2)
There are a few things that could be affecting your bass response.

First, brick walls are more reflective at bass frequencies than glass so your former room would have reflected more bass energy back into the room and the current room will be "leaking" more bass energy through the glass.

Second, you didn't mention whether or not either room has permanent openings or is part of an open plan area. Those sort of things affect bass response and differences of that sort between one room and the other may be having an effect.

Third, you didn't mention room size and differences there can have an effect.

Fourth, bass is affected by the proximity of the speakers to surrounding room surfaces. While the speakers may be the same distance from the front wall as they were in the previous room, they are likely to be different distances to the other walls and ceiling which can affect bass response. You may be able to improve response somewhat by moving the speakers closer to one or both of the front and side walls.

Finally, where you sit has an effect as well. If you're sitting in a modal low pressure area you will hear weaker bass than you will in some other locations in the room. If its possible, try moving the listening position backwards or forwards along the midline between the speakers and see if you get better bass response at another listening position.

From the one point you did mention, I would think that there would be less bass energy overall retained in the new room and you would notice that as a weaker bass presentation. On the other hand, depending on just what was happening in your old room with room modes as a result of the brick walls retaining bass energy in the room, the actual bass response in the old room may have had strongly pronounced peaks and dips while the peaks and dips in the new room may be less extreme because less bass energy is being retained. What that means is that you MAY actually have a smoother bass response in the new room (note the "may"�I'm not saying you will have and it would take measurements to find out) and it's also possible that the bass in the new room may be more accurate than in the old but once again you would need to compare measurements in order to find that out. Unless you actually have measurements taken in the old room, such comparisons may be impossible so you may never know for certain.

One thing is certain, however. Your expectations for bass response will have been formed by what you were hearing in the old room and you will have brought those expectations with you. A lot of your initial response to the sound you're getting in the new room is going to come as a result of hearing something different from what you're used to and were expecting. Over time you'll start to adjust to the sound of your speakers in the new room and when you do adjust you may find your reaction to the bass response you're getting will change. If you are getting smoother response you will start to appreciate that. You may find you're getting deeper extension in the new room (and you may not) and start to appreciate that. After somewhere between a week or two and a month or two in the new room, depending on how much listening you do, your opinion of the bass response you're getting in the new room may be somewhat different to your initial response and it's worth waiting for that adjustment to occur before making decisions about any changes.

If you want advice on acoustic treatment possibilities for the new room, then you're going to have to provide more information about the room including details of room size and construction, and whether or not it is part of an open plan area or has permanent openings such as archway entrances, plus where those openings are in relation to the speakers and listening position.

David Aiken
- RE: Lack of bass - amdan 03:21:35 08/02/10 (1)
  David - thanks very much for your thorough response. It is much appreciated. I have managed to improve the bass significantly by moving the speakers closer together.
  I will look at the other factors you mention as well. I would like to install bass traps however the traps I have are too big for the space in the corners. Would a roll of rock wool which is about a foot in diameter and about 3 feet high help much if I installed it in the corner?
  - RE: Lack of bass - David Aiken 13:09:03 08/02/10 (0)
    "Would a roll of rock wool which is about a foot in diameter and about 3 feet high help much if I installed it in the corner? "
    
    Will the rock wall work as a bass trap? Probably, and the roll design that you mention is basically what Jon Risch recommends for his Quick and Dirty Bass Trap except he uses fibreglass. Do a search in Tweakers Asylum for his posts on his design for some further info on that approach. The reason I said "probably" is because I'm not certain how the rockwool will compare to fibreglass when used this way but rockwool has been used successfully for bass trapping so it should work. Whether it will work more or less effectively than fibreglass is a question I can't answer.
    
    Will "a roll" work? If by "a roll" you mean a single roll in only 1 corner, I'd say don't bother. At only 1' diameter that's a small roll and even if effective, single bass traps tend not to make big differences in a room. I think you need to treat a minimum of 2 corners in order to start achieving useful results and all 4 corners is better. Floor to ceiling treatment is better than half room height or less, and bigger (ie wider and/or thicker) traps than your 1' roll are also better because, besides absorbing more, they tend to absorb to lower frequencies as well.
    
    David Aiken

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