Taming room acoustics

Chaps,

I'm hoping that you can give me some inspiration.
I moved house a couple of months ago, and am still trying to get the right side of my new lounge (listening room).

My old lounge was basically a rectangle of about 6x4m, with the system firing sideways across it. In it I had major problems with a bass hump that virtually refused to be tamed.

In my new flat, I have a somewhat odd shaped room, with a curved wall opposite the system. In addition I don't have much soft furnishings.
Either way, I get a VERY bright top end and the bass sounds almost as though it is actually recessed.
I've been trying a few ideas, but all to no avail. I changed over my speakers for a while tonight, just incase it was them. My normal rear speakers are ported stand mounters, and even with them mounted against the wall, the bass was not really even flat.

Anyone got any good ideas?

 

turn the speakers around to face the wall :JPS:

 

why not? it works for me

 

So is really Phill Babb, Jimmy hughes is disguise

 

The first thing to say is that the top end and bass problems are completely separate and have to be sorted individually.

I got a real shock when I first played my speakers at the High End Show in Frankfurt. The room was square and had concrete walls all round. It sounded like a large bathroom. The first day of the show I turned up with a blanket and a duvet and I nailed them to the wall. It helped.

So, if the room's very bright at the top, you can treat it. Paintings, rugs, bookshelves, soft furniture can all help mop up the brightness. What if you move the speakers further away from the wall to increase the proportion of direct to reflected sound? Does that help?

Re. the bass, a recess sounds like you've got the speakers in a room anti-node - or you're sitting in one. As an experiment, place one speaker on top of the other in a corner. That should couple the speakers to the room bass-wise. How does the bass sound like that?

With the speakers in the corner position, try walking about the room listening to the bass at different locations. You'll start to get a feel for the room, its nodes and anti-nodes.

You can treat the room with bass traps and the like. You could try to measure the response to get a handle on what's going on. However, experimenting with placement of speakers and listening position is the first step. You can also treat the sound electronically to compensate. I haven't done this so I'm no expert. Merlin and Wadia Master are two of our resident experts on this forum. Mind you, it's easier to reduce peaks in the response than it is to fill up the troughs.

Finally, a separate sub (or subs) can be easier to position in a room. It ain't easy finding a position that's good for mid-range, imaging AND bass.

If everything fails and you still have a problem with your new flat, MOVE. You've got to get your priorities straight you know.

Good luck
Steve

 

Originally posted by Mr_Sukebe

Either way, I get a VERY bright top end and the bass sounds almost as though it is actually recessed.



Hmmmmmmmmm.....

This does sound as if it could be a mains power related problem..... I have heard this before in various locations and the following may help....

Have you tried cleaning all the mains plugs in your system??? Give the plugs a REALLY serious cleaning with a Scotchbrite scouring pad...you know the one...its that green one... be carefull not to touch the metal part of the pins after cleaning as the grease from your fingers will contaminate them....you could alse treat the pins after cleaning with some De-oxit...this will keep the pin clean for a long time.

If you do get/have some of this De-oxit....treat all the used signal connections as well...

If you want to have a look at the Tips and Talk section of my website this may help in speaker positioning also.....

Regards

 

I suppose you've checked that the speakers are in phase.

Steve

 

Only one thing will work for sure, parametric equalisation... :JPS:

 

If the bass response has troublesome peaks then parametric equalisation could be one way to go. However, in this case Mr_Sukebe is talking about a recessed sound. It's much more difficult to fill in a trough in the response.

Above the low frequencies, parametric equalisation will cause more problems than it solves.

Steve

 

The solution is obvious youve said it yourself - youve not got enough soft furnishings in your room.

I cant believe everyones not saying the same thing:

Get a load of rugs, back them with something thick.. like a few layers of carpet underlay, and hang them at the points of reflection behind , to the side of speakers, and behind where you sit.

Also a big fat rug on the floor aswell.


thats it.

Chris

 

I agree that first you have to get the room right, meaning speakers position and furnishing, EQ works mainly with bass ressonances...

 

Thanks for the ideas so far chaps.
I'll have a chat with the missus later on so we can at least complete a "test" with some soft furnishings in a variety of places.

I'll also try to find the room nodes. It did occur that nodes seem more common in corners/against the walls. I wonder whether having the sofa approx 1m from the rear wall has an influence.

 

I'd bet that it does. Place your head nearer the wall and if the bass is improved, buy the wife some flowers and beg permission to move the sofa back.

And remember, upgrading the wife would be much more expensive than upgrading the hi-fi.

Steve

 

Just to add that it sounds like a mid bass suckout, would you say you are losing the energy in the music, giving a thin weedy quality to the sound?

 

Ah! finally, Dr. Merlin to the rescue. What took you so long? Some people should take their heads out of their vinyl collection and stay on the ball a bit.

Steve

 

I wouldn't call it weedy, just unbalanced. If the optimum result is a ruler flat frequency response between 20hz-20kz, then imagine the flat ruler response as a see-saw, with someone sitting on the bass end of things.

 

btw its meister not miester. who is jimmy hughes?

 

he is aware

 

sorry i did not realise

 

Therein lies your problem.

First of all, please explain 'odd shaped' in a bit more detail. Normally 'odd shaped' is what you want, but your room may not be ideal from an acoustic point of view. I think you have the classic 'live' sounding room scenario.

In order to help counteract this problem, you should try hanging pictures or rugs on the wall, or anything else that breaks up reflections. Furthermore, as has been suggested, get some more soft furnishings in the room, particularly things like large sofas with plenty of cushions on them and thick-ish curtains. If you have a wooden floor, put a large rug in the middle.

Something else that doesn't often get mentioned but highly influences the sound is room temperature. It may sound overtly simplistic but (in general) a 'cold' room makes for a 'cold' sound, and a 'warm' room makes for a 'warm' sound. Do you have central heating in the flat? Try putting a small temperature gauge in your room and ascertain what temperature makes for the best sound. Maintain this temperature consistently. Also keep your system switched on at all times.

One other thing, are your speakers facing the window wall? In my experience, this can sometimes give an overall brighter tonal balance than when the speakers are facing towards, say, the sofa and the back wall. Lastly, mains supply is important. You could be unlucky enough to be in a location with poor mains quality (high levels of Radio Frequency Interference and other forms of distortion) compared to where you lived before. There are many things that can be done to help cure this problem, if you're interested, just ask.

Marco.