your listening room is your biggest problem

[dominicT]

Hello

We have talk a little bit before about the effect that a room has on the sound that our speakers make. Whilst we cannot turn our rooms into recording studios and a 'dead' room is not always desired, colouration can be nice, I just thought that I would point out that month after month in Sound On Sound www.sos.pubs.co.uk in the studio rescue pages, it is the spaker positioning, room reflections, wrong room shape, etc etc that is mucking up the ability to get a good mix. I think that we should pay more attention tot he room and where and how we set up our gear.....and also to read SOS a bit as they have some really good articles that would also apply to hifi.

DominicT

[merlin]

Ah room problems:cry:

I remember those.....:JPS:

[lowrider]

With a bit of planning, one can do a pretty good job, still keeping the room nice and conffy... :MILD:

But next week I will have TMREQ to make it "perfect", I wonder if it will make that much difference... :rolleyes:

I sure will let you guys know... :beer:


See Merlin, my avatar is now music, no more hifi... :duck:

[adam]

I personally believe the room to be the most important factor when deciding on what speakers to buy,and how they'll work within that room,as it's size, construction will affect the final outcome.

My current room is from hell,as it gives a massive hump at 45hz,which has been virtually impossible to erradicate,ive used the cara test disc to try to help with some success,moved the speakers around to try to find the best placement,but the room just keeps the hump in,it's probably too small at 3.5m x 3.5m,but is dead sounding with no echo,but still manages to screw the upper bass right up.:(

[test tone]

The room and equipment set-up therein is not so much important as absolutely critical. Yet the basic fundamentals of acoustics are too often overlooked by audiophiles more interested in pseudo-scientific nonsense such as that peddled by the cable industry.

Adam,

Quite right. It's not unusual for speakers (especially bookshelf) designs to exhibit a 'knee' in the LF response. If this coincides with the primary room mode then in-room bass response will likely be compromised.

Room modes themselves are a factor of room size, and are an innevitable consequence that can be controlled, limited, but never wholly eradicated. When setting up your system are you able to move the listening position as well as the speakers?. If all else fails it may be worth considering a bass trap?.

[adam]

That was the beauty of the cara test disc, as it did a 45 second sweep of all freqs,it enabled you to walk around the room,even though small it was easily discernable to hear were the modes were worse,as you walked closer to the walls it was so nausiating from 54hz-43.

Intrestingly there was no deep bass at all,at about 40hz you could hear nothing,but when playing music,you think you getting deep bass,but your not it's produced at 50hz,and is as you say hard to entirely elliminate,which is odd as in my older house,same construction a tad bigger,faced no such problems.

Bass traps.....yeah nice idea,but exspensive and rather unsightly.

[MO!]

What exactly is the score with these test discs? They just do a freq' sweep and you walk around the room? How much? where from?

[adam]

Mo i ordered mine from www.cara.de It was 18€ for the disc but you can order a pc programme to,it produces some intresting results if you find that your room is causing havoc on the system,and as i said the closer you get to a wall the more profound the effect.

PS...you cant dance to it.

[lhatkins]

Cheers Adam, been looking for a program like that, it doesn't cost the earth either which is unusual for HIFI things, so someone finally sees sence then.

HEHE my system causes havoc to the room! On certain bass notes I've found the lamp shade gives off a very strange vibration noise, it took me ages to figure out what was making the noise!

[themadhippy]

why pay for test discs?theres loads of free signal genarator software on the web,Also software like cooledit have the facilaty to produce alll sorts of coloured noise ,frequncy sweeps,single tones ect.might even be avalible on the free demo;)

[lowrider]

Hey guys... hifi existed before all those programs, with some common sense and moving speakers around a bit, we can get pretty good sound, as long as you are not trying to use huge boxes in a small room... :MILD:

[themadhippy]

not trying to use huge boxes in a small room...
who me :MILD:
http://www.inthebog.fsnet.co.uk/speaker6.jpg

[lhatkins]

If ya speakers / furniture is light, then yes lumping it around the room to get the right sound by trail and error is ok, but my speakers and dam heavy so I want to get it right first or second time, so if I can use a program to calculate the best postion for them in my room then that takes the hard work out of it, my listening room isn't square, if it were I'd have no problem, but I have a very odd shaped room with chimney and 2 walls either side that are not at the same angal, so its a complete nightmare, it always sounds like my music has a left bais and I can't solve it, and I'm sure its the room.

[MO!]

Originally posted by themadhippy
why pay for test discs?theres loads of free signal genarator software on the web,Also software like cooledit have the facilaty to produce alll sorts of coloured noise ,frequncy sweeps,single tones ect.might even be avalible on the free demo;)

and where might such a freebie be found?

[Mr_Sukebe]

I also had a massive problem with bass at 40hz in my old room with my floorstanders.
The best method I found to improve things were concrete slabs under the speakers. It certainly didn't eliminate the problem by a long way, but helped to control it.

As it happens, I've recently moved and the new place seems to have hardly any "hump" at all.

[Ian J]

Originally posted by MO!
and where might such a freebie be found?

There is an interesting site here (http://www.snapbug.ws/bfd.htm) which is supposed to be for setting up a Behringer Feedback Destroyer but it also contains other useful information plus a series of test tones to download.

It is mainly used for setting up subwoofers but can also highlight problems further up the frequency scale.

[michaelab]

If you've got a laptop with a decent soundcard (ie one with stereo line in (a mic input will not do) and stereo line out) or you're prepared to lug a desktop into your listening room :eek: then the best software around (for a reasonable price) for doing room measurements and analysis is ETF 5 from ETF Acoustic (http://www.etfacoustic.com/).

You'll also need a mic or preferably an SPL meter with a line out (eg the Radio Shack digital SPL meter easily available for £20-30) and some longish (listening position to amp) ICs (any old black and red cheapies will do) and some RCA "Y" adapters.

I first heard it mentioned in the Tag forum as an essential tool for setting up the Tag RoomEQ system (in the AV32R DP and AV192R AV processors) but have since used it to excellent effect for setting up and configuring my sub.

Test tones in 1/3 octaves will only get you so far, even with an SPL meter. The ETF software is very accurate - as Lowrider will agree :D

Michael.

[HenryT]

Personally, I reckon the idea of getting a pair of speakers that'll best in your choosen listening room is a better starting point, and then you can fine tune around the speakers and use acoustic treatments as a last resort.

For those that listen in rooms with boomy mid-bass (circa 50Hz), I would strongly suspect that speakers which "couple" to the room very strongly are best avoided e.g. reflex/port loaded design. Also choosing speakers with minimal tweeter/main driver side splash and diffraction effects would also help in the cause to minimise room interaction.

Some of the best system I've heard have been in what appear to acoustically awful rooms on first sight. Sure, a flat response is a must for recording studios and probably home theatre, but not so much for pure music system, IMHO. Best to avoid room interaction/interacing in the first place rather than try cleaning up the (unnecessary) aftermath. :)

In any case, what if you spend all this money and time on building and restructuring work and don't like the sound at the end of it? It's going to be a right pain to reverse the work, depending on how radical work was.

[lowrider]

I will do my TMREQ with test tones and SPL meter, then Michael will measure to see how well I´ve done... :rolleyes:

[adam]

Originally posted by HenryT


For those that listen in rooms with boomy mid-bass (circa 50Hz), I would strongly suspect that speakers which "couple" to the room very strongly are best avoided e.g. reflex/port loaded design. [/B]


Couldn't agree more that ported speakers are a P.I.T.A. but using sonus faber concertino homes,small box/driver still manages to tricker of room modes,is frusrating,only by closer the port complety can i reduce that lump in the bass,plus virtually all speakers seem to come with boom ports.

[dominicT]

Sorry have been away and not able to contribute. The things that SOS advise to 'fix' room problems are in part about speaker placement but much more about understanding about the contribution that the room makes to the sound, for eample if two dimensions of a room are equal (as one poster here has) then you will have a problem with standing waves. Fixes do include things like base traps which need not be expensive and any more unsightly than a sub-woofer. Other tricks are to use a duvet pinned to various positons on walls to determine where to soak up sound and then to apply acoustic tiles where the duvet indicates. Typically this is on the opposite wall of the speakers. There are various things that you could do such as mount a number of acounstic tiles on a piece of MDF and cover it with an attractive piece of fabric to create a piece of art that also serves as a very effective room correcting device. This is the sort of thing that we need to be looking at first and foremost rather than reaching for the paving slabs yet there is little talk of it here. Is it lack of knowledge or a fear or making our rooms unsightly. There are products out there than are cost effective and look good or can be camoflaged.

what do you think?

DominicT

[wadia-miester]

Room interaction is very real and hard to 'cure' problem that effects nearly all Hifi systems I feel, having a definate K2 bass peak in my system with my previous speakers :D Much to the amusement of a few members :cool:
Over time this has been greatly reduced, my first speaker x/over mods, much less bass interaction and cabinet rattling, then changing I/c's helped more, next better speakers wow, what a difference, better placement of said speakers, power mods, again better, I don't believe any one thing is the total cure all, but 'Room Thangs' I feel are purely about clear signals, less defractions, and reflections, how you deal with them is total indivdual system idiosyncratics. WM

[technobear]

Pinning duvets to your walls will do nothing for a 50 Hz bass hump. It takes seriously LARGE absorption to soak up bass that low. Either you need to fill the back quarter of the room with mineral wool (not very practical) or you need LARGE membrane absorbers. Tube traps are not effective down to 50 Hz whatever the marketing droids might like to have you believe.

If you can, put your listening chair one third of the way into the room from the back wall. This will minimise the effect of the worst front to back standing waves.

Chris

[themadhippy]

Originally posted by MO!
and where might such a freebie be found?
signal genarator http://www.dazyweblabs.com/sg2102/index.html
cool edit 30 day demo http://www.syntrillium.com/download/

[Graham C]

Originally posted by technobear
Pinning duvets to your walls will do nothing for a 50 Hz bass hump. It takes seriously LARGE absorption to soak up bass that low.
Chris

Thats if the absorbtion is near the walls. Try absorbing in the middle of the room, as described here:

http://www.bruel-ac.com/tr/tr9602/tr9602.html

[bottleneck]

Originally posted by Mr_Sukebe


As it happens, I've recently moved and the new place seems to have hardly any "hump" at all.

????
:SWMBO: :spank:

:D

[technobear]

Originally posted by Graham C
Thats if the absorbtion is near the walls. Try absorbing in the middle of the room, as described here:

http://www.bruel-ac.com/tr/tr9602/tr9602.html Good link. My own absorbers are designed to space the mineral wool away from the wall by a few inches and this increases their effectiveness considerably.

One interesting line from that link...

"So by 50 Hz where the wave length is 6.8m the thickness of the [absorbent] wall has to be 80 cm to give some absorption and 1.5 m thick to be good. If this large volume has to be filled with mineral wool the price for the last octave at lower frequency will be extremely high."

See what I mean :p

Chris

[dominicT]

Originally posted by technobear
Pinning duvets to your walls will do nothing for a 50 Hz bass hump. It takes seriously LARGE absorption to soak up bass that low. Either you need to fill the back quarter of the room with mineral wool (not very practical) or you need LARGE membrane absorbers. Tube traps are not effective down to 50 Hz whatever the marketing droids might like to have you believe.

If you can, put your listening chair one third of the way into the room from the back wall. This will minimise the effect of the worst front to back standing waves.

Chris

Chris

The duvet test is to identify where to put absorbtion panels so that you do not have to hang heavy panels to the wall and move them about every five minutes. Absorbtion panels about 2' square in size each do work as evidenced month after month in SOS (www.sospubs.co.uk) which is why I have brought it to the attention of those here.

[technobear]

Originally posted by dominicT
Absorbtion panels about 2' square in size each do work as evidenced month after month in SOS (www.sospubs.co.uk) which is why I have brought it to the attention of those here. I've had a look through the site and whilst there is much discussion about bass traps, I cannot find any mention of these 2' x 2' panels. Could you find us a link?

Chris

[lhatkins]

Originally posted by wadia-miester
Room interaction is very real and hard to 'cure' problem that effects nearly all Hifi systems I feel, having a definate K2 bass peak in my system with my previous speakers :D Much to the amusement of a few members :cool:
Over time this has been greatly reduced, my first speaker x/over mods, much less bass interaction and cabinet rattling, then changing I/c's helped more, next better speakers wow, what a difference, better placement of said speakers, power mods, again better, I don't believe any one thing is the total cure all, but 'Room Thangs' I feel are purely about clear signals, less defractions, and reflections, how you deal with them is total indivdual system idiosyncratics. WM

Ya that bass was certainly amusing, if not AWSOME! but really enjoyable (to a bass lover like me!) I've not heard the new setup thought, but HenryT seems to like it (he keeps visiting, so he must like it).

But its all in the construction of your room / house isn't it? Being totally solid concrete block all around, solid floor. My recollection its a oblong room, with not real potentional problems, I thought the glass fronted cabinets would give you a problem, know how much glass likes to vibrate, but we didn't hear that rattle.

It looks like the Mrs wants to move and solid wall / hifi friendly house isn't on the cards, I may have to contend with Plastboard walls, (oh god no!!), then I've lost my bass for good.

[domfjbrown]

Originally posted by lhatkins
It looks like the Mrs wants to move and solid wall / hifi friendly house isn't on the cards, I may have to contend with Plastboard walls, (oh god no!!), then I've lost my bass for good.

Or you could move into my flat with solid walls and floors and have no bass too... Grrr...

Hippy - so THIS is what your kit looks like:
http://www.inthebog.fsnet.co.uk/speaker6.jpg

Groovy - those speakers are huge - are they quite sensitive due to the size of the cabs?

[dominicT]

Originally posted by technobear
I've had a look through the site and whilst there is much discussion about bass traps, I cannot find any mention of these 2' x 2' panels. Could you find us a link?

Chris

Hi Chris

You need to look for the Studio SOS features in each magazine. April 2003 issue is a good one because the reader upgraded his speakers but they were still not right. There were real problems with the bass end as well as the high frequencies. The room and speaker placement were the problems. A top guy from Genlec came out and measured the room etc. You will need to be ab e-subscriber to read the article online which is why I have not been able to link through to anything for you. I am a magazine subscriber which is why I cannot cut and paste. regardless of the problem that the team go out to fix, they nearly always do something with the monitors because there are always things that can be improved. It is worth bearing in mind that these visits are normally to home studios (big studios can help themselves) and obviously the owners do not want to rebuild their houses.

You can also look up Canford Audio on the web. They are the largest studio supply company in the UK. They are very helpful and can advise on sound treatment. http://www.canford.co.uk/

Hope that this helps.

DominicT

[technobear]

Thanks Dominic. I'm still toying with the idea of trapping deep bass so all info is helpful.

Chris

[lhatkins]

Originally posted by domfjbrown
Or you could move into my flat with solid walls and floors and have no bass too... Grrr...


Are dom but that's the speakers that have no bass, not the room, plus you don't play it loud enough cos you don't want to upset the holiday home owner downstairs!

In fact "if" we "do" get the one she's looking at, I'm going to have a complete nightmare trying to get my hifi in the living room, 3 doors, fireplace, abolutly no room to put a hifi unless I put shelves on the wall! (hum didn't think of that).

If we get it I'll draw up a plan and we'll see if the collective brains of the ZeroGain forum can figure out how I'd put a hifi in there. Its big enough 4.9m x 3.10m, so don't know, anyway might not get that one.

[test tone]

themadhippy,

Serious looking enclosures. I can't tell from the photo, but are they on a plinth?. Or is it a slot port or transmission line terminus?.

[themadhippy]

that there slot is the tunning port,or at least thats wot i designed it for,they can do a good impresion of a boy racers sub bins if the mood takes me:JPS:

[test tone]

Originally posted by themadhippy
they can do a good impresion of a boy racers sub bins if the mood takes me:JPS:

But minus the Nova with obligatory LED washer jet lights I take it? ;)