Room Acoustics

Posted elsewhere but doesn't seem to have generated much interest. Am I the only hi-fi Jedi who's turned to the dark side of acoustic treatment??


I wonder why the subject of room acoustics and acoustical treatment is so overlooked by hi-fi enthusiasts and the hi-fi press. I find this quite surprising given that room acoustics are the single biggest influence on sound quality after the components themselves.

A further irony is that hi-fi enthusiasts will happily spend hundreds, even thousands, on cables, power cords, mains conditioning etc which at best bring only subtle improvements and often (arguably) make no difference at all. A few hundred pounds spent on room treatment brings real and tangible improvements and (if you wish) this can be measured with a microphone and the appropriate computer software. There's no voodoo science or pixie dust here.

Possibly because the subject of room acoustics is such a viciously complicated one with complex mathematics and physics involved it's avoided. But this doesn't mean the basics cannot be easily grasped with a little thought.

I consider my bass traps to be as much an integral part of my hi-fi system as my interconnect or loudspeaker stands. One up each corner does wonders to flatten the low frequency response of my listening room giving tight and clean bass even at high volume.

Consider the room as the canvas on which the hi-fi system must paint its picture and you're halfway there.

 

Totally disagree, good quality mains IMO is the biggest influence on sound after the hardware...you must have heard some of the naff snake oil products which tend to dominate the hifi market place And then you could also try a pair of transmission line speakers which work very independently of the room. Yes, the room can affect the sound to degree, but I've always been primarily interested in musical improvements, so the whole room acoustics issue takes a back seat for me, it's far too hifi.

 

I've found the room to have a huge influence on the sound, even with my treated mains and transmission line speakers. The reason I have not done serious room treatment is because I have not had my own place to do so. However, when I move into my new house soon then I will be doing just that, expect more info in a while...

 

Try hanging some drapes behind your listening position,and tell me what you hear.

I agree, the mains supply can be important,but if you've got shite room acoustics,the equipment(or mains) is not worth bothering about.

Paul.

 

i think the big problem is that every room is individual - even more so that is usual in the hi-fi world. even 2 rooms that are exactly the same can have wildly different sonic signatures due to differences in the placement of kit and furnishings. this makes taking one persons experiences and translating them to your own circumstances very difficult.
at least that's my take in things. also most room tuning devices either look like an eviscerated pipe organ or have a degree of voodoo attatched (the harmonix stuff). lastly big pipes with carpet stapled to the outside are nowhere near as sexy as the latest uber amp or cd player.
cheers


julian

 

Well surely we know why it is not discussed? Because every room is different, and because to treat heavily would totally affect the appearance of a room. I'm sure we all agree that its a good thing to do when it's feasible.

Quickie, I agree with 'dead end' behind the listener, especially if you are near the wall
If you want suggestions for a typical rectangular room with big speakers, put something in the middle of the floor to disrupt standing waves. Either something large to bounce sound off [eg table and chairs, or build a drinks bar in the middle] or something soggy like a sofa, bed, jumbo bean bags etc. Course then you have to sit at one end and arrange the speakers for line of sight at the other end, maybe high up, without too much side reflection off the walls - tricky? definitely. As long as the room has mains, my hifi works OK.

 

..Just as Julian said first!

 

My post is based upon my experiences, and I have tried most things when it comes to attempting to improve hifi sound. Each to their own of course. I've actually got shite room acoustics at the moment, having recently moved into a new place and not got it sorted out yet, but my hifi is still as pleasurable to listen to as it always was. My point is that acoustics (to my ears at least) affect the sound, not the musical aspects, of hifi, whereas good mains fundamentally improves the musical aspects as well as the sound quality.

 

Congratulations to MrC for providing the funniest post of the year so far! Bravo

 

'Room treatment'

lol,only something a single bloke ahs time to think about.If I tried that,I would be a eunuch in seconds,even for just thinking about moving the furniture about

 

So long as you believe this to be true who am I to disagree, keep lapping up the marketing fluff.

There is no such thing as loudspeakers which are able to “work independently of the roomâ€Â. Not unless you happen to live in a house made of paper. If anything transmission line 'speakers are designed to interact strongly with room boundaries to extend low frequency response. Sealed enclosures are the least room dependent design.

 

With the addition of some 'lovely' hanging drapes as a suitable façade for bass traps it's possible to increase the WAF by at least 70% !

 

eh? have ever seen House Doctor?! Anne Maurice would NEVER have any drapes

 

mosfet,
having just moved from a traditional ported speaker (cdm7 nt's) to a pair of transmission line monsters (IPL s5tl's) i've found the ipl's to be more benign when it comes to exciting room modes than the 7's ever were.
as a born again batchelor i can put my speakers where i damn well please and had the 7's pulled out pretty far into the room, at least 1 meter from any room boundary. with them positioned as best i could i still had some very strong room interaction. it was obvious as you walked from the speakers towards the back of the room that there was some very hefty reinforcement occurring about where the main listening position was.
whilst the ipl's aren't totally without this behaviour you really have to work hard to hear the room modes and finding their position is not an easy matter.
also i've heard a similar thing happen when tony moved from his monitor audios to his meadowlarks.
the only sealed box speakers i've tried havbe been some little mission 700's which didn;t excite any room modes afaict mainly due to their weedyness - they were fun though.

as for curtains well just check the my kit liunk below for my idea of stylin' drapes.

cheers


julian

 

Having just redecorated and taken out my DIY treatments, the room now sounds about 300% worse but looks 300% better.

 

Companies like Auralex (www.auralex.com) are starting to take domestic room treatment seriously by introducing more discrete and/or stylish (i.e. not pig ugly) acoustic panels, bass traps, etc. Check out their domestic ranges on the website to get an idea.

Personally, I have just over 100 quid's worth of Auralex foam panels on the walls of my listening room (being a bachelor I just went for the regular studio stuff ) and it makes a really noticeable difference. The biggest thing it does is let you play louder without the music getting congested and harsh, which can be as much a factor of room effects as the hifi equipment itself. At louder volumes in particular, the midrange is a lot cleaner and clearer, and the treble a lot smoother. It also allows greater freedom for speaker positioning - you can place them closer to walls without as much muddying and congestion in the mids and treble.

Eventually I'm going to get more acoustic panels, and hopefully some bass traps, but it was worth just taking the first step with a few panels to clear up major reflection problems.

Dunc

 

I agree that room acoustics are a dominant factor and that control of the reverberant sound field is a very important.

In my experience, there seems to be alot of confusion regarding the use of sound absorption treatments as apposed to sound diffusion treatments. They are both equally important but sound absorption seem to get the most attention in hifi circles.

If sound diffusion treatments are used carefully, the amount of sound absorption needed can be reduced in many cases. A highly diffuse reverberant sound field is more pleasing to the ear when compared to a sound field consisting of highly specular reflections (i.e. sound reflections of plain, flat pastered wall). I would recommend anyone contemplating room treatments gets a handle on these two differing treatment methods first.

The room modes problem is the hardest one to crack IMO and I think that some form of room equalisation hardware is the way forward there (but I haven't gone down that line myself yet!)

 

Speaker/room interactions are imho the biggest influence on the sound a system makes.
However speaker design, sorting the mains (after all it runs your whole system) and isolation do a marked effect on the sound also.
Now finding out which order does the business for you, as ALL rooms and kit are different is down to experiance

 

Yep, I can agree on that, nicely put.

 

Very nice 'speakers Julian.

Perhaps now your free from spousal objections you could also build some Superchunks http://forum.studiotips.com/viewtopic.php?t=535


In an ideal world we'd all have dedicated listening rooms with mini-bar and resident lap-dancer.. :MILD: