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Advice on adding reflecting surfaces

Kvalsvoll

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Exactly. I tried to hang Knauf fluffy rockwool on walls and it was very useful. But totally not acceptable for normal life, of course.
My 1st reflection on one wall is door and window blinds, so I need to use something rigid in their frames.

In the room described in my link, there is no side-wall treatment for 1. reflection, due to practical issues. And it does show slightly worse early-reflection attenuation compared to what has been achieved in other rooms. But sometimes you have to compromise, and the overall result is still very acceptable.
 

CapMan

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D4BD6E5D-45B9-40B6-817B-7DC270B5B08B.jpeg

why are the walls made from ceiling tiles??

get rid of them (carefully - they may contain asbestos)

use drywall and "plaster"

you can find the 1st reflection points with a mirror and a holder for the mirror - if your gf doesn't yet think you are insane then this will likely push her over that edge...
If you are using REW a great way nail the reflection points is to look at the ETC curve. You’ll see the initial impulse at T=0 then a series of easy to discern spikes . These are reflections. Using the time stamp of the spike and speed of sound (343m/s) you can calculate how much further the reflected sound has travelled . Add this value to the mic to speaker distance , cut a piece of string this length . Attach each end to speaker and mic then gently pull the centre of the string towards the walls floors / any other hard object . It’ll hit somewhere and that’s the reflection !

I’ve attached an energy time curve for my room - blue trace is no absorbers in room, red trace is side walls, ceiling, rear wall.

The aim is to attenuate the spikes by at least 20dB in level over the first 20ms . These spikes are the ones that the brain tries to blend with direct sound from the speaker and chase imaging issues
 

CapMan

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In the room described in my link, there is no side-wall treatment for 1. reflection, due to practical issues. And it does show slightly worse early-reflection attenuation compared to what has been achieved in other rooms. But sometimes you have to compromise, and the overall result is still very acceptable.
Hi - I got some panels from eBay (blue frog audio) - the frames are solid timber and just needed me to add some wooden feet so I can use them freestanding . I have one I front of a bay window
 
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FeddyLost

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I’ve attached an energy time curve for my room - blue trace is no absorbers in room, red trace is side walls, ceiling, rear wall
What is the size of your room?

Mine is pretty small and distance between speakers and MLP are much longer than to walls and floor, so ETC looks really bad with relatively low overall RT.

Now I understand that everything should be built another way, but it's still OK to consume and no big changes are possible without total mayhem...

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CapMan

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What is the size of your room?
It’s small and irregular in shape. 3.55m wide, 3.75m long, 2.3m high. There is a bay window on the left side and an angled doorway on the right . To make things worse the right hand wall is an internal partition and the left hand wall is external !

I downsized my larger speakers last year to small sealed monitor types and added a pair of SVS 3000 micro subs . This has given me a lot more control than a single pair of full range speakers .
 
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FeddyLost

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I downsized my larger speakers last year to small sealed monitor types and added a pair of SVS 3000 micro subs . This has given me a lot more control than a single pair of full range speakers .
To get better LF I did 2.2 with sealed subs and optimized placement.
This straigtened things below crossover almost completely, but i.e. midbass is still extremely messy.
 

puppet

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Could a guy take 6"x6" squares cut out of 1/4" thick plywood and using short brads, at each corner of the square, just press them into your acoustic tile? You could add in the required amount of reflection without too much major alteration to the interior surfaces.
 
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