2 Channel Speaker Placement Need Help

I placed the speakers 4 feet from the back wall, and created an equalateral triangle all sides 9 feet apart. That helped dramatically. The bass lacking issue was due to my small adcom GFA 5200. I just tested an NAD THX 218 250 watt per channel power amp that was lent to me from a HiFi audio store and within 5 minutes the right channel was blown! Amp was wired correctly and didn't even push over 100 watts to the speaks. I will also try all your suggestions. Thank you! -Keith

As a test of what wall treatments might do, hang some blankets on the walls. This is a cheap way to tell if some improvement will help. If the blankets provide improvement I would go for the real thing. Plenty of information on the site about that.

Try this method. When all else fails, try a new method:

http://www.hifi.ir/wp-content/uploads/2009/03/master-set.pdf

Good luck and keep trying.

While reading your post I had a strange thought. Is there any chance that one of your speakers was ever repaired and connected backwards to the terminals? Try wiring one of them out of phase and see what happens. I did this in college to a neighbor that would run his stereo early on Sunday mornings playing video games. It was on the wall opposite my bed so I took things into my own hands. It almost sounds like you're in the situation that I put him in.

Also, your Washington and Manchester made me think that we were neighbors, but I'm actually on the opposite coast.

I will keep that in mind and give it a try. I just tried hooking up an average sony reciever to my adcom preamp and found the results interesting. The SQ of the Sony is lacking, however I could not notice a difference in the midrange and tweeter reflections regardless of where I was in the room. This may just be due to the bad sound quality of the sony, however I was told that mixing bright amps with bright speakers can indeed cause more reflections/bad results. I am thinking of switching the amp to an a/d/s/ PA4 or PQ20 and seeing what results I get as well. My speakers are rated for 325 watts per channel, and are only being pushed with 80 watts per channel in a fairly big room for that amp. Do you think if I ran an appropriate size power amp (adcom gfa 555 or 5500 325 Watts RMS per channel) that it would help my problems as well?

Getting speaker placement right takes some time and patience. I do recommend trying to get speaker placement right without any room treatment first, for when you get the speakers in the best location you will notice less room interaction. Also you will achieve the best bass responce in the right location. The 1/3 rule does give you a good starting point and then move the speakers around concentrate on first getting the bass responce right first.

As for treatment and reflections keep in mind you only need to treat one parallel surface not both. Except on the side walls you want to keep the treatment of side wall reflections symetrical. You want to treat the back wall behind the listener, not the front wall, and then as little as possible on the side walls generally where the speakers first reflection back to the listener, ideally with some sort of defusion panels rather then absorbtion. Problem with absorbtion is its not linear in its absortion characteristics, meaning it will absorb at certain frequencys and reflexed at others causing comb filtering. I personally think you can acheive excellent result with typical materials we all may have around the house, light curtains, area rugs, etc. Try different materials starting with the lightest materials first, to get the desired results your looking for. Reflections are good they just need to be controlled and delayed. The difficult issues are bass nodes, which speaker placement will help in that aspect significantly.

Any other questions feel free to ask

Kevin
40 years hi-end audio video specialist

1) The reflections are not particularly in a certain frequency range, but mostly the midrange and bass. In most all setups I cant hear any bass and the midrange lacks terribly. The imaging is also pretty bad. The bass does not overpower the room as the M15's lack bass extension.

2) This is the first time I have setup these speakers in an apartment. I figure the shape of the room has a big effect on the reflections. Speakers are aimed towards the door however the shades are closed. Kitchen is behind the speakers.

My Dad owns the same speakers and has them setup in his living room, which is odd shaped but the speakers are far enough from everything that I cant hear any reflections.

3) Room is 18.5 x 12 feet pictured here: http://www.forrent.com/apartment-community-profile/1000053208.php

4) In accordance to the picture of the living room above, I have placed the speakers on each of the 4 walls. Speakers were pulled at least 2-3 feet from each wall if not further. My best setup was the speakers being placed on the south wall in front of the balcony aimed toward the kitchen. Placed 4 feet from back wall, 2-3 feet from side walls. With the speakers aiming forward (not toed in) they sounded great when standing in front of either speaker. In the middle (designated listening position) all I could hear were the reflections, no bass etc. Tried toeing in speakers 45 degrees to a/d/s/ spec with worse luck. In other words with the speakers aiming forwards they sound the best when I stand about 3 feet from each wall. Thanks for your time and I appreciate any help! -Keith

I probably can't help you with setup, but will try to ask some additional questions to aid those that can.

(1) Are the sound reflections in a particular frequency range? Is the bass overpowering the room?

(2) Have you sucessfully set these speakers up before in a similar sized room?

(3) What is the general shape of the listening room? The apartment I've lived in generally had odd shaped living rooms.

(4) What have you tried so far?