On 12/8/2024 at 4:20 PM, Keith_W said:

first reflection point.

Hi Keith

the problem with addressing first reflection points, is I do not really have first reflection point.  On the left side, I have a 3m glass sliding door with drapes, I am really not sure how the glass reflects with the drapes down.  With the speakers 1.4m from the front wall, where they were for this measure, the 1st reflection is the large opening to entrance, hence why I am considering applying some treatment to the entrance.

however, I am considering creating some first reflection points, this may also help with symmetry.  I could use some type of office divide, say 1.8m high by 1.2m wide and place some 600w diffusion panels in the centre.  I could also create some reflection, simulation a gyprock wall, by installing Gyprock or Perspex either side of the panel, or something else (just ideas for now).

I have just moved the speakers back closer to the front wall, this may actually create a 1st reflection point on the right side.

My first action is to install a couple Absorption panels, mainly at the rear, and see how this goes, then will take a look at the 1st reflection points next - a bit of a step by step approach

You could consider a solution like this: 

 

 

 

SNA won't let me paste the link directly so here it is. Remove all the spaces and it should take you to the thread. 

 

w w w. audio science review.com/forum/index.php? threads/ delayed-first-reflections.45678/

 

 

Wots the WAF rating on that hot mess @Keith_W😁

Might sound good though👍

12 hours ago, Keith_W said:

You could consider a solution like this

Hi Keith

Funny You suggest that.  I have considered building something like this, not dual layer, but creating small walls to make my room more normal, like a shoe box with four walls, I thought about timber frame with Gyprock, or office divide with Perspex, but timber, not you have me thinking.  Thanks.  Could always build a couple of these, stack them when not in use, and if needed, apply absorption or diffusion where needed.

A leaky room can be a good thing, as I do not have many of the issues a shoe box room has, but creating typical issues that you can hopefully fix is a different way of addressing the problem.  Thanks

i have bought some absorption panels to start with, and moved my speakers back closer to the wall, I will see how I go from there.

FWIW I am in contact with the guy who installed those gobos in his room. He designs acoustic treatment so he's pretty smart If you are interested I could ask him for more details. 

Progress report

i have installed six Primacoustic Broadband absorbers (1200x600x50), 4 across the rear wall, and one either side of the listening position.  These panels dropped the midrange and high end 1k to 10k down to about the suggested line in the FR graph @Keith_W shared.  Did I notice any difference in the SQ, not really, maybe everything sounded a little tighter.  I am still very ineffective at interpreting these graphs, but I am pretty sure the decay times reduced as well.

I then installed 2 x Hybrid Panels acting as Diffusers at the first reflection point.  Here there was a noticeable improvement in the SQ = I liked.  However, upon measuring the FR, the midrange and high end basically went back to where it was before, but I really liked the SQ.  So in summary, 6 x absorption panels at the rear and sides reduced the mids and highs, then 2 x Diffusers at the first reflection point placed the mids and highs back to where it was.  Now I am only looking at one or two of the results, but I am a simple man.

what it tells me though is that there could be better places to place the absorbtion panels .  So I am going to play around a bit and Trial placement, see what my ears tell me and compare to the measurements, so some fun to be had.

today, I will move the Diffusers to behind the speakers, and try the absorbers beside the speakers, and then at the 1st reflection point.  I also want to trial absorbtion in the entrance and hallway, I reckon I get more reflection from the entrance then the rear wall.  And then there is the “off limits ceiling”, need I say more.  My walls only cover about 50% or less of my room, so I reckon that most reflections are coming from the ceiling, and or the entrance.

Either way, my SQ in my opinion is pretty bloody good, I just think it can be just a bit better with some minor peaks.

I'm late to this thread - but generally agree with all the responses.

 

This looks good, but as others have pointed out, some EQ down low to lop peaks off, and general EQ to dial in a room curve would likely improve the sound.

 

In one of @Keith_W earlier posts he included an example of a "room curve" in red.

 

I've implemented my own "room curve", somewhat smoother than the red line, but similar.

To me it sounds more balanced and natural.

 

@JkSpinner - do you have DSP EQ capability?

 

A "treatment only" solution is not likely the best path to the best sound in your room.

 

If you choose to add a sub, you should include DSP EQ also, ideally able to apply DSP EQ across your main speakers also...

...heresy for many - but "good integration" of a sub with main speakers requires the ability to manage crossover frequency, slope and delay between mains and sub for best summing.

As a bonus you can apply a room curve also.

 

EQ gets a bad rap - it can do great good or great evil.

Well applied EQ can benefit enormously:

• never use EQ to fix sharp dips
• lopping off peaks with EQ cut is generally fine
• generally use EQ cut and boost broadly

Mike

14 hours ago, almikel said:

do you have DSP EQ capability

Hi Mike, no room correction for two channel, only HT.  As with subwoofers, it doesn’t mean it is not on the list, just not now.

I am using Keith’s graph as my bass line,  the four panels along the rear wall brought down the response over 1kz, but it remained flat.  And brought the RT60 numbers down as well.  I then installed two diffusion panels at the first reflection point, and it kind of took it back to where it was, but the diffusion panels created a sq that I enjoyed.   Hence why I am playing around.

My gut feeling tells me I might need to look at the ceiling, and or the adjoining tiled echoey entrance and hall way. When I apply a high test tone, the high pitch noice and echoe in the entrance is unbearable, so it has to have some effect n SQ in the listening room.   I will probably try placing a few panels n the reflection points in the entrance and hall way, and see what effects that has.

i am going to move the absorption panels to the first reflection point, and compare to the panels on the back wall.  I have the diffusion panels behind the speakers for now.

my gut feeling tells me I will add some addition diffusion panels to the front wall, and maybe the 1st reflection point, and strategically place absorption panels beside the speakers, on the brick wall and the rear wall, and maybe the entrance 

6 hours ago, JkSpinner said:

I am using Keith’s graph as my bass line,  the four panels along the rear wall brought down the response over 1kz, but it remained flat.

Try dialing down your treble control, and see if measurements approach the proposed "room curve".

 

6 hours ago, JkSpinner said:

My gut feeling tells me I might need to look at the ceiling, and or the adjoining tiled echoey entrance and hall way. When I apply a high test tone, the high pitch noice and echoe in the entrance is unbearable, so it has to have some effect n SQ in the listening room.  

You could try some WAF friendly treatment in the hall/entrance like floor rugs, which will only absorb treble.

Any thin absorption will help in this area - 50mm absorption with prints/artwork will be WAF friendly and soak up treble in the entrance way/hall way.

6 hours ago, JkSpinner said:

My gut feeling tells me I might need to look at the ceiling

You've already said treating the ceiling is not conducive to WAF support - you don't need to go there yet!

Other than cost, I'm sure that a DSP/EQ solution would have more WAF support - but you don't need to go there yet either.

 

I'm a massive fan of room treatment, but I use it in conjunction with EQ and a sub.

 

I applaud your approach of fine tuning with treatment!

 

Keep tuning and measuring and post results!

 

cheers,

Mike