room acoustics again!

P

penance

Arrogant Cock
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we moved our room around last week to try and make better use of space.
The speakers now sit infront of a bay, they are out in free space away from the actual bay but inline with the angled wall of the bay.
It seems to have had a detrimantal effect on the soundstage, everything now comes from one spot central between the speakers. Im not panicing as i know my setup has sounded better. I would like to try and sort it out without having to put the room back as was because the layout is better and with more space.
So i im guessing i need some kind of treatment for the wall of the bay (curtains over windows when listening), but i dont know what i need, damper? diffuser? anything else?
 
You could try the closing the curtains when you play some music and see what effect that has.

If you clap in the listening room is there an echo ? How does the sound decay ?

I think you need to bring the speakers forward a touch 6 - 8" as your losing the side wall reflections that help to make up the soundstage imagery.


At least the sound is in the middle and not located arround each speaker.

Have you turned them in a touch?

The other though is that you have a big distance behind the speakers and so the rear wall reflection is reduce to nothing.

I'd play about moving them forward and back and further appart see what effect that has.
 
What happens to the image if you sit to one side of the hot spot?

How far apart are the speakers?

How far are you from the speakers?

Chris
 
the curtains are closed, but to be honest there isnt any difference if they are open or not
ive tried moveing them around but couldnt get it anybetter, i may try moveing them further into the room tonight (away from the bay)

the speakers are currently about 6' apart and around 8' from the listening position
 
Hi P,

Have you tried messing about with the toe-in on the speakers yet?

IMO, it's a good start that you at least have a decent solid central image between the speakers. It should be just a case of toeing the speaker's tweeters to face further outwards i.e. more towards the sidewalls or pointing straight down the room as I'm guessing you have them angled slightly inwards at the mo so that the tweeters are pointing more towards each other?

Differences of only a small fraction of inch can make a huge difference to the perceived central focus and left/right spread of the image produced from the speakers.

You usually have to trade off central image focus against lateral left/right spread of sound. Some people prefer more solid/palpable central image, whereas otherwise prefer a more diffuse and wrap around sound.

HTH.

:)
 
spot on Henry, they are toed in at the moment
ill try changeing that tonight
im sure i have already, to be honest i messed around so much over the weekend ive forgotten what i tried and what i didnt:rolleyes:
 
Hey squable squable I ask that first !!

Yep sounded like they were toed in, Ribit[toad] Ha


The advice is sound [sic] What your probably hearing is the true sound of your speakers ! what a thought.

You have achieve a near anechoric responce, and really that not good.

What to do.......? Well get some wall behind them, even a little may be enough. You'll know when you start to move them about.

Let us know what happens.
 
penance,

It seems to have had a detrimantal effect on the soundstage, everything now comes from one spot central between the speakers.
Click to expand...

This is the focussing effect from radiated energy impacting a concave or parabolic reflective surface. Think microwaves reflecting off a satellite dish, and focussing onto an LNB. It's a well known acoustical phenomena, and one that; in a domestic situation, such as this; may not be easy to cure. That is, unless you move your speakers back to where they were.

Minor absorption, such as that from a curtain will do little or nothing. To negate the problem fully you'd have to completely absorb the cavity, then build a parallel diffuse wall into the cavity. Else, fully line the bay area with diffuse panels. And fully line means all of the bay area, especially the glass. Less drastic measures - try and at least get some parallel wall space behind the speakers. Then, perhaps very heavy curtains allied to some form of diffusor panelling (pyramidal or wedge foam perhaps) for the wall areas of the bay. Or even more minimalistic - freestanding diffusor panels behind - but to the bay side - of each speaker.

Did you not have problems before the move? Rooms with concave areas such as bay windows do tend to have either problematic bass response, and/or soundstage/image anomalies.
 
You've not accidentally switched your amp into mono during the move have you (assuming your amp has such a switch - I understand some do).

You weren't listening to a mono recording by any chance? ;)

I'll get my coat :D
 
The most interesting part of this whole problem is the clear demonstration on how vital acoustics are to sound quality.

My best guess with this problem is revolving around side reflections and not the rear radiation, although I doubt it is helping anything. Generally speaking, side reflections give the perception of space, although this depends on the type of flooring material and height of the ceiling. As the ceiling is presumably fixed and the flooring has not altered it seems to be a matter of how the sound is reaching you.

Defusors etc are powerful tools but throw them into a room with due calculations, in my experience, will more often hurt the sound quality.

A quick test for the rear section to gauge it effects would be to add a large sofa or chairs and review the changes.

Disclaimer: It has been a long time since I last reviewed any acoustic papers - so I could be way off the mark, but try adding large soft chairs etc behind the speakers.
 
bit limited on space to add chairs etc behind speakers

ill keep moving them about but i am starting to think of putting the room back as was

i do have some large cushions that i may be able to stick behind the speakers to see if it helps, i guess if that helps then i could try some DIY treatment

gotta say that it does seem to sound a tad harsh at times aswell, i guess thats the window behind it
 
Last edited by a moderator:
Originally posted by zanash
Hey squable squable I ask that first !!

Yep sounded like they were toed in, Ribit[toad] Ha
Click to expand...
Apologise to you there Zanash. :respect:

Just re-read the thread and spotted this:

Originally posted by zanash
Have you turned them in a touch?
Click to expand...
Must have been the heat in our not so well air-conditioned office yesterday afternoon... :zzzz:

:)
 
moved speakers around last night and im happier with the sound, tho it seems better sometimes than others:confused:
Also realised last night that the socket it is now hooked up to is a spur from the ring, so im now thinking i need to start my dedicated supply sooner than i thought
 
ive played around for a fwe days, moved them in so as to get some parallell wall behind but that didnt work.
So they went back to were they had been in the bay and i decided i would leave it and see if the grew on me
well im sat there last night and moved over about 2 foot from center listening position (to avoid the pin sharp cat claws!) and bleedin hell, it all became good. so it seems the the best listening position is actually just of center to the left. I think this might be because the right speaker is closer to a side wall than the left.
so do i need to do anything or should i leave as is?
 
I wonder if you can alter the speakers a la audio physic .
Basically what happens when you set your speakers up as the audio physic approach , you may find that the image is not central .
you can pull it back to centre by not having the speakers symetrical . basically you would toe in , toe out one of the speakers until the image moved to centre .
the other one you can try is to move the one speaker slightly more forward (or back) and this will also help shift the image back to centre .
hope this helps .
:)
 
Glad you found the sweet spot !


How big is it ? I'm lucky mines half a sofa wide, and spookily right were the sofa is !
 

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