Speaker placement

[Claus Es]

Hi there. I have a pair of Snell A/III which I recently purchased 2nd hand. I have been experimenting with their placement in my listening room, and I haven't found the perfect spot yet. The most prominent problem is some nasty bass resonances from standing waves in the room. I have heard that the speakers are designed to be placed somewhat close to the backwall, but in my situation that kills the cleanness and imaging (from more early reflections I guess).

How do I optimally fix this. Are spikes under the speakers a good idea? My room is 5.3 m wide and 6.5 m long. The speakers are standing 1.9 m apart in the middle of the 5.3 m wide end wall, 1.1 m from the back wall, and 1.75 m from the sidewalls (measured from the treble driver).

I have heavy curtains on all the back wall, but they don't really change much drawn. Should I make/buy some acoustic absorbers / bass traps?

Thanks!

[Guest Bluzmaster]

Boy! There are a number of possibilities, here. First of all, The "near to the wall" bass response deal refers to placement of approximately 12" - 16" or so from wall. But I am referring to the type A, and I realize it may be a little different for yours because they have rear-firing super tweeters, don't they?

Other placement considerations are their proximity to the side walls. This concerns unwanted reflections from the tweeters, mostly, but bass response is also definitely affected.

As far as standing waves, there are a few things that may help, short of rebulding your room w/ angled walls... First of all, I would add as much deadening as possible. Tapestries, high-quality acoustic ceiling tiles, heavy drapes, carpet, soft furniture. And at least one wall-surface with irregular, random shapes, like a stone wall, will break up the standing wave effect.

Also, you could angle the speakers a bit to avoid directly ping-ponging the sound. In the owners manual for the Type A, they suggest an optional placement of the units more out from the rear wall, but L'd out from the side walls and angled slightly toward listening area.

Lot's of things to try. Mostly low-tech, common sense trial and error. You'll get it.

B

[Guest Raintree Sport]

Boy! There are a number of possibilities, here. First of all, The "near to the wall" bass response deal refers to placement of approximately 12" - 16" or so from wall. But I am referring to the type A, and I realize it may be a little different for yours because they have rear-firing super tweeters, don't they?

Other placement considerations are their proximity to the side walls. This concerns unwanted reflections from the tweeters, mostly, but bass response is also definitely affected.

As far as standing waves, there are a few things that may help, short of rebulding your room w/ angled walls... First of all, I would add as much deadening as possible. Tapestries, high-quality acoustic ceiling tiles, heavy drapes, carpet, soft furniture. And at least one wall-surface with irregular, random shapes, like a stone wall, will break up the standing wave effect.

Also, you could angle the speakers a bit to avoid directly ping-ponging the sound. In the owners manual for the Type A, they suggest an optional placement of the units more out from the rear wall, but L'd out from the side walls and angled slightly toward listening area.

Lot's of things to try. Mostly low-tech, common sense trial and error. You'll get it.

B

[Guest Raintree Sport]

First posting - I just picked up a pair of EIII that need some TLC. Woofers surrounds are shot, walnut vereers are dried out and stained. Its a project! I orered a foam surround repair kit on-line, and will try that for the first time. What is the concensus on placement? Close to the rear wall? Toed in? Is it a high or low order XO? Thanks!

[Carlspeak]

Taming bass resonance issues is not an easy task. Adding lots of abasorbtion items like drapes and rugs, ect. won't help bass problems much. They are much more effective with higher frequecies.

You may have a room mode issue. There are many free computer programs on the net for calculating room modes. Try a few to see how your specific situation fares theoretically. Another approach is to borrow or purchase an inexpensive sound level meter. Radio Shack sells one for about $50. Secondly, purchase a test CD with frequency tones and use the two together to see if moving the meter back and forth a few feet in the area of your listening chair registers a significant variation in dB level at a low frequency you find particularly objectionable.

Hopefully, your test data will be reasonably close to the room mode computer model; in which case you can then experiment with different placements of the speakers (on the computer) to see if a better speaker arrangement can be found.

Bass traps are indeed another way to dampen low frequency resonances. Real Traps offers products which can help with your problem. Visit their website www.realtraps.com

There is lots of advice and a room mode calculator and free downloadable test tones there. Their illustrations seem a bit loaded with their products which they are trying to sell. However, you prlblem may be solvable with fewer panels.

As with all room acoustics issues, YMMV.

Good luck!