Positioning Vandersteens


This is a two-part question and since the parts are related I think one post is appropriate. First part is regarding a recent thread about speaker placement in dealer showrooms in which a couple of folks commented on the difficulties in properly placing Vandersteen speakers. This is interesting since I am in process of trying to get my 3A Signatures properly located in my somewhat small room. I’m having difficulties, primarily with a bass boom, and was hoping someone might be able to relay their experiences with siting Vandersteens. Comments on whether these speakers are appropriate for my room (see below) would also be appreciated. The second part of the question relates to the room itself, I recently measured the room with my Radio Shack SPL meter (using the Rives Audio test procedure and the Stereophile Test CD) and found, to my amazement, that the room was only flat from 400 Hz to 1000 Hz, the readings dropping off steadily such that at both 100 Hz and 10,000 Hz the readings were 20 dB down. This seems rather extreme to me, anyone else have similar findings? Specifics on the room, overall it is 17’ 3” by 14’ 8” with 7’ ceiling, however, it is reduced in size by a partial, full height wall through half the width making for a 13’ 4” by 14’ 8” space where the speakers are. To make matters worse there is some ductwork (boxed in and insulated) running along two walls. Because of the odd shape most or all of the acoustic software for siting speakers won’t work. Particulars of the system: Audio Research SP-9 MK II, Audio Research Classic 60, CAL Tercet MK IV, VPI HW-19 MK II, McIntosh MR-71, and PS Audio P-300. Some assistance in this process from those who’ve been there done that would be greatly appreciated!
pmotz
1. For bass control try experimenting with distance between speakers and the wall behind them, and with placement of your listening chair, relative to the wall behind it.
2. In the room you describe, I would concentrate on optimizing a near field listening position. I own a pair of Vand. model 3s, and prefer them in the near field.
I agree with Judit. I used to have a pair of Vandersteen3A Sigs and found that the instructions that Vandersteen provides work very well. To minimize some of the problems you are having with bass control, I would suggest moving the speakers away from the wall (I had them about 38" away, rear of the speaker to the wall) and aiming them towards the listener, with the speaker axes crossing just behind my head. The vertical tilt of the speakers is extremely important, since the vertical band in which they sound good is extremely narrow (only about 6" high!).
Pmotz, for acoustic modeling software that works in odd shaped rooms take a look at CARA CAD. My room is L-shaped, has a cathedral ceiling w/beam, irregular end wall heights, etc. and CARA modeled it just fine. The results match fairly closely those from an SPL meter and test tones.

CARA doesn't completely replace experimentation. It does provide useful insight into what is happening acoustically which aides in decision making and "what if" scenarios.
I also agree with Judit & Kweifi, I moved my 3A sig 4 feet from the rear walls and added 2wq's, It's heaven when you get it right! Tilt is the tough part, I had to order extra spacers to get the angle right with my listening height. But it's worth the trouble, I never think about my speakers any longer, I just listen to the music, never been happier with any purchase as I am with the Vandersteen 3A sig. Take your time and listen, when you get it right you'll be pleasantly rewarded, well you already know, that's why you bought them!
Good Luck.
Follow the Vandersteen instructions to get a general placement. The speakers need to be out from your wall at least 3'( if not closer to 4'). Using the instructions, divide your room up and use the measurement that gets them out at least this distance. You know, the divide by 3, 5 ,7 thing. Do the same for the distance from the side wall. Once they are set in a general location, measure their distance apart and set your listening position back approximately a foot from this position eg. distance apart 7 feet, distance back to chair would be 8 feet). Then measure to the listening point(acoustical center) to the chair. This needs to be about 8'. Any closer and the speakers don't have enough distance to blend. The speakers will actually look closer than 8' feet if you go from the centers. Now, set your tilt back about 1/4" MORE than the manual shows. Sit down and see what you have. If it doesn't sound right at this point, I would try another wall and reset. It should sound focused and pretty decent. You SHOULD NOT be required to aim the speakers at your chair or listening point. They should image well facing straight ahead or with a slight inward angle (about 5 degrees) If they don't, again, try another wall. If they have to be aimed at you or behind your head, something is not right.
you will have to balance the distance from the wall for best bass vs. best imaging. Without subs , that is all you can do. There will be NO perfect place that will yield best bass with perfect imaging and soundstaging. No speaker will. And people can call me nuts on this issue if they want to! You can get good but NOT perfect bass vs mids and highs integration.
Moving out from the wall should alleviate your bass boom. You also must place the SPL meter at the listening position at the proper height or you will get a poor picture of the actual frequency response. Also, you do realize that the Radio Shack meter has a few errors in the actaul response that are frequency dependent. A couple of points about 4 db off. However, you should be able to get a pretty good picture.
It took me about 3 months to get my 3A Sigs and pair of 2WQ's set up. It was very trying but worthwhile. Little 1" movements make a difference. Using the above should get you close if you are on the correct wall. Good luck!
Thanks for all the reponses! For information, I have followed the Vandersteen set up procedure for the current location. The acoustic centers are about 35" from the rear wall now, the next step using the Vandersteen procedure is about 58", which is the 1/3 dimension. This will put them very close to the listening position, but I will try in the next few days. I may also try on another wall, though that requires moving all the equipment, ugh! One problem with these speakers is they are very difficult to move with the spikes/cones. I've gouged the floor more than once!
One thought (Pmotz), remove the spikes and place the speakers as close to thier proper listening positions as possible. Now replace the spikes and make the final adjustments. Saves your floor!

Thanks
Contact Mark at Audio Perfection in Minneapolis...or better yet...Richard himself...
hi...i am math illiterate. i have the vandersteen 2 ci's and i dont have the manual that goes with them. my room is 13' x 9.75, speakers on the short wall. would anyone be kind enough to do the math part for me and give me a general idea of where they should be placed? right now i have them 4.5 from the rear wall and 24' from the side walls. no toe in. my listening level is 33". thanks in advance.
something to consider...

as much as i love the arc classic 60. it may be a little to underpowered in this situation.

also, as good as the vandersteen 3a signature is, it may be too big in your room.

you have very, very good gear and a tight room.

i would condsider going with the vandersteen 2ce signature(believe it or not, less is more in this situation- better fit for your room and a good match with arc classic 60 ) or adding another classic 60 for biamping the 3a's and looking at ALOT of room treatment options. what you are experiencing is a standing waves that are resulting in ALOT of cancellation. ydue to your room size, it cannot support deep bass. you will be lucky if you can get 35 hz.

hope that helps,

mike