[medium jim]

One of the most difficult things to do is getting truly great bass in difficult rooms and would appreciate those who have gone through the process to post here.   The hope is that this thread will become a reference point sticky thread.

Thanks,
Jim

[Devil Doc]

I used Jim Smith's book and DVD and recommend them highly. A whole lot of fiddling around, though. especially without an RTA. Wrecked my back moving my flippin' chair and speakers around for the smoothest bass. Finally got to with-in +/- 3dB down to 31.5 Hz. I used test tones and a rat shack spl. meter. Not ideal, according to smith, but it's what I have. It was worth it but what a pain in the back.

Doc

[max190]

I wouldn't say great but I would say coherent bass...
What got me there was 1st a lot of trial and error moving my spkrs around then addressing the 3 open corners with GIK 244's, also placing 1 each on the FW center and directly behind the LP. The other corner is the entrance to the room and I leave that door open.

[JohnR]

Hopefully it's OK to post links... here are links to Parts 1 and 2 of Paul Spencer's Bass Integration Guide:

http://www.hifizine.com/2011/06/bass-integration-guide-part-1/
http://www.hifizine.com/2011/09/bass-integration-guide-part-2/

(Part 3 will be published in a week or so.)

[JerryM]

Hopefully it's OK to post links... here are links to Parts 1 and 2 of Paul Spencer's Bass Integration Guide:

http://www.hifizine.com/2011/06/bass-integration-guide-part-1/
http://www.hifizine.com/2011/09/bass-integration-guide-part-2/

(Part 3 will be published in a week or so.)

Super cool, JohnR. 

[medium jim]

I just don't know and welcome those with expertise or first hand experience to share their knowledge. 

Jim

[kevin360]

In a word, it's critical. Having said that, I must confess that I need more. It's been nearly two years since this project began (we had the lot cleared on June 21, 2010), and there's still work to be done. Another problem is that I blew my budget out of the water - the project cost me twice my initial projection (kept thinking of things to include). I can't stop fiddling with the damn system - just purchased some tubes and...

Okay, I promise to do more by summer's end.

[SoCalWJS]

I put wedges of OC703 in the front corners of my room and was happy with the results. Mellowed out a nasty dip centered at about 57 Hz, took care of a couple of smaller dips around 125-160 Hz (using Omnimic to get measurements), and helped the soundstage with regards to focus and depth.

I cut each panel into 4 triangular wedges and ended up with stacks 4 feet tall in each corner that are behind bookcases that are angled to go directly in front of the wedges and hides them from view. I would like to add tri-traps on top of these stacks that would raise the treatments all the way to the ceiling, with a finished product showing above the tops of the bookcases.

I am a firm believer in the significant improvements bass treatments make in my system. 

[kevin360]

I used some of that same material, but I placed it behind the sheetrock when building the room. Actually, it's attached to the back of the studs and there's foam between it and the wallboard. I didn't have to worry about making it pretty, but is that location effective at all? My actual objective was trying to keep from disturbing my neighbors and I can enjoy rather substantial bass without complaint, so I accomplished that goal.

I need more trapping - I know. This is the most challenging part of an audio system to get right because the damn room is so influential.

[Diamond Dog]

I am a firm believer in the significant improvements bass treatments make in my system. 

+1. Using a combination of GIK product here and it was definitely $$$ well spent.

D.D.

[medium jim]

I stumbled across this article:

http://www.ethanwiner.com/acoustics.html

Jim

[TRADERXFAN]

Geddes method involves a few subs,  and, ideally, wall damping (Constrained Layer Damping) construction for optimum results.

Here is specific info and setup process adapted from Geddes recommendations
http://mehlau.net/audio/multisub_geddes/

[TRADERXFAN]

The Welti multisub paper

http://blog.acousticfrontiers.com/storage/low-frequency_optimization_using_multiple_subwoofers.pdf

[TRADERXFAN]

Double Bass Array
or Controlled Acoustic Bass System

Using rectangular room with specific many sub drivers positioned on walls and cancelling time delay equipment to get extremely smooth bass response. Requires that there is very little deviation from perfectly rectangular in regards to openings etc...
 

http://www.avsforum.com/avs-vb/showthread.php?t=837744

Can use google translate from german
http://de.wikipedia.org/wiki/Double_Bass_Array

[TRADERXFAN]

http://jamesromeyn.com/home-audio-gear/dsa-1-0-distributed-subwoofer-array-5-pieces-4k-usd/

DEBRA multisub approach. Details here.
Placement method almost at end of the page.

[WGH]

There is a lot of excellent information about setting up bass speakers in a stickied link in the Acoustics Circle:

Loudspeakers, Rooms, and Subwoofers - Audiophile Articles

Floyd E. Toole, Ph.D. and Todd Welti can get very technical in some of these white papers but there is a lot of tips in between the formulas.

I add new articles as I find them, this month's addition is a white paper about designing the perfect room including sections on room proportions, background noise, reverberation time and control of early reflections.

Wayne