Room Treatments added, with negative effects..

Sorry Sir,

Fres le jaque, fres le jaque, de main vous, de main vous...

Well, folks I think I solved the complex room treatment challenges...... by removing the *$(%&#@ treatments altogether. From the effects I was getting, it's hard for me to see how these absorbtion treatments can have any benefit. I'd still be open to experimenting with tube traps and defraction type treatments (although those two seem like pricey experiments compared to the cheap foam), and I'm still of the opinion that room set (especially speaker placement) up can have a huge impact on sound quality. That said, I think I'm done with this foam stuff. Thanks to all for the suggestions though. Cheers,
Outlier.

No, no, how could I be a contrarian? I never yes, I never say no, quite the contrary.

So, it's all in your head?... :-)

Outlier,

I'm not surprised to read that you have had a miserable time w/ these foam acoustical treatments! When I was in the market for acoustical treatments, the $150 package was mighty tempting in lieu of buying ASC tube traps. In hindsight I'm happy that I didn't buy these foam treatments & bought the ASC tube traps instead. These traps are awesome & have done wonders for my room & as you rightly said, they are phenomenonally expensive! I had mid-bass & upper-bass boom that needed treatment.

1st, you never told us what was wrong w/ your room! What are you trying to correct for or are you just jumping on the acoustical treatment bandwagon? Different issues require materials & some of the room issues just cannot be solved with passive materials (& require a TacT or Rives-like unit). It would be nice if you could (anyways) let us all know what you were trying to achieve.

Foam panels are acoustic velocity absorbers ie. they absorb higher freq. & high freq, usually above 400Hz. It is no surpise here that they "deadened" the sound! These panels absorbed the high freq & left you with the mid-bass & lower thereby giving you a dead-like sound. BTW, for acoustic velocity absorbers to work, they must be placed atleast 4" from the wall where there still an acoustic velocity of the sound wave! Once the acoustic wave hits the wall, the velocity goes to zero & the foam panels do not act on a zero velocity wave. In contrast, ASC tube traps are acoustic pressure absorbs (bass is acoustic pressure). One hemisphere is reflective & is used to reflect 400Hz & higher. The cool thing about ASC tube traps is that when one uses it to reflect 400Hz & higher that reflective surface is away from the wall by the diameter of the cylinder. This occurs naturally as the reflective side faces the room (rather facing the wall surface)!! So, one doesn't need to make stands or any such thing to get the reflective side to work correctly.

My suggestion to you (as some others have also pointed out earlier) is that you keep some panels to treat the 1st reflection off the side wall next to the speakers. Here, make a 4-ft tall frame from 2X4 from Home Depot. Make a stand for this 4-ft tall frame so that you can free stand it anywhere in the room. Attach 2 2'X 2' panels (to create a 4' tall X 2' wide) using Velro to this frame. Place these panels in front & to the wall side of the speaker so that it can "treat" the 1st side wall reflection. You will have to play with exact position. Now, I have assumed that your tweeter is not higher than 4' off the floor. If your tweeter is higher then you will have to make taller panels or simply raise the 4' tall panels off the floor.

Like the others, I do not recommend using more panels behind the rack/back wall or behind your listening seat - it'll deaden your sound as you have already found out. Use them only if your room is very lively.

For bass traps, you can roll your own. Try Jon Risch's receipe. In yahoo! search for the name "jon risch" it should bring up his website. There is tons of very, very good info there. I have found his info to be accurate (he is trained as an acoustics engineer) & my friends have used his panels receipe with great success.

IMHO. FWIW. YMMV.