Brightness update

[Womaz]

In general: the thicker the absorption the more acoustic energy it will absorp over a broader frequency range. Thin sheets of absorption will do little to nothing for the lower mid/bass frequencies and only some for higher frequencies. Thicker sheets will absorp more highs and at a certain point also become more effective at mid/bass frequencies. This is the exact reason it is so hard to battle room modes, you need a lot of absorption material and thus space to tame those. There's other solutions to "trap bass" as well like my RPG Modex panels which are "spring loaded" sheets of metal against a softer absorber. These are specifically tuned/designed to absorp small band bass frequencies only. Above applies most to the soft, foamy materials.

Professional manufacturers will supply charts of absorption coefficients for their products. These will display how effective they are in absorbing the the different frequency bands, at least between 125Hz and 8kHz.

As an example and to just illustrate what I mean have a look at this datasheet: http://www.primacoustic.com/pdf/EDS/prim...oadway.pdf

Earlier I wrote that I hired an acoustics expert who measured my room and then modeled it to simulate the required type of materials and their locations. I'd still advise that for a complete approach instead of a point solution or a trial and error approach. Of course one can do it for himself but without modeling upfront and measuring while you go you're in the dark. Key to good acoustics is the right amount of absorption and diffusion and balance to acquire an even broadband absorption over the whole frequency scale. But of course in an entirely untreated room without much "natural" absorption almost anything will help.

Once again thanks for the detailed reply. I dont really want to go to the full lengths of a proper consultant out to my home. Up here in Newcastle the nearest one will probably be about 200 miles away anyway

I read all of the articles on the GIK website which is how I come to the same conclusion as you about diffusion panels. To be fair to the lad helping me with the enquiry he gave his recommendations based on full room treatment. So I have emild him back asking if his recommendation would change now that I am only treating the back wall, behind my listening position. I would imagine it should do, but I will await his reply.

To be honest i will go for it as I have been looking to add something to the back wall for a little while and the panels could even look quite attractive as there are a lot of colour options.

The other option is the speaker cable my dealer will let me try for a week or so. I guess I am favoring the room treatment as I think that they will have the biggest impact and even if they dont make a great deal of difference they could look quite good on the wall. At a cost of just under £400 it will not really be that much of a gamble.

I really appreciate all the comments and help with this thread, some excellent help as usual.

[Womaz]

I'm more than ready to be corrected, but I'm a little sceptical that treating the back wall (i.e. just behind your listening position) will have much effect on perceived brightness.

I share your reservations. This is why i have emailed them again for clarification. I think he said the bigger bass trap panels helped with all frequency levels. I may be simplifying it too much as I am only looking for help with the high frequencies, i thought diffusion would be the key.

To be honest though I have very little knowledge in this area and I have to trust them in their recommendation. Will be interesting to see what they come back with

[thumb5]

Yes - fingers crossed - will look forward to hearing the outcome.

[completeluxury]

thumb5 i agree with your comment... without the side walls done i wouldnt expect all that much.

Rug on the floor/side walls and rear wall should be the minimum.

treating the back wall only is just going to make you come back and ask what else can be done to tame the brightness!

[Womaz]

But maybe it is better than nothing. It's my living room and not just me who has to like it. I thought that side walls ceiling and back walls would just look awful .

[baddog]

Just my two cents, given all the comments so far - absorption or diffusion on the wall behind you should help in regards to the brightness. Given how small the distant from the back wall to your seating position they may well recommend absorption rather than diffusion.

If you could put another panel between your two front speakers that would help as well, but I don't know if that will work given your other considerations for the room.

[Womaz]

Just my two cents, given all the comments so far - absorption or diffusion on the wall behind you should help in regards to the brightness. Given how small the distant from the back wall to your seating position they may well recommend absorption rather than diffusion.

If you could put another panel between your two front speakers that would help as well, but I don't know if that will work given your other considerations for the room.

Thanks for the post, I will see what they come back with today.

[Womaz]

Just my two cents, given all the comments so far - absorption or diffusion on the wall behind you should help in regards to the brightness. Given how small the distant from the back wall to your seating position they may well recommend absorption rather than diffusion.

If you could put another panel between your two front speakers that would help as well, but I don't know if that will work given your other considerations for the room.

They have replied and basically confirmed what you were thinking. Absorbers rather than diffusion for the back wall as I only sit a foot away from it. So they say I need to absorb as much as possible in that seating position. If i was a meter or two away from it then this would change to some sort of diffusion. Also if I was treating the side walls too, then diffusion would be recommended.

[Womaz]

Ok an update for all those who have contributed. I have decided to get 4 bass trap panels for the back wall. A gamble worth taking I think.

Also I reverted back to 7.13 a few days ago and at first did not notice a difference. However I kept using it, mainly because I could not be bothered to do the configurater again. Today I reverted back to 8.13 and for me there is a touch more of what I dont like. A little bit brighter in my opinion. It is very small but I have now gone back to 7.13 again.

[baddog]

Hi - if GK recommended Absorption on the back walls ( especially behind the listening position ), were bass traps what they recommend, that strikes me as a bit odd, what panels did they recommend, and will they be behind your listening position?

Just asking, not impugning....