Bloody room acoustics

[farflungstar]

So I've been living wth a null area for bass for a long time and it's always pissed me off that bass output just hasn't gone as low from one channel. I've had the speakers on the long wall of my rectangular room - something I read was the best some 20 years ago. Recently this has changed and people say to put firing down the length of the room. So today I did this - I even bought a lovely leather listening chair - guess what - no bass at all unless I'm away from the listening area and standing up. Very very frustrated by it all.

[farflungstar]

So I've spent the day moving things around and still cant get the bass to even up or firm up. If I stand behind the speakers then lots of bass. If I sit in front then a reasonable amount now and better but still not as much as I'd like. The weird thing is if I turn the balance full to either speaker there is loads of bass - but turn it back and it's like they cancel each other out.

I've checked all connections and they are fine - vocals are rock solid centre - guess i need to move house!

[Lerxst]

Really stupid question: Are they wired out of phase? Wouldn't be the first time! It's just you say with balance turned to one side it come back

[farflungstar]

No they are fine. It was my first thought.

[farflungstar]

I will try wiring the bass out of phase tomorrow but the problem is neither the amp, or the speakers.

How could a room cause bass cancellation - in front but wallops of it behind.....


To help...

The room is about 7.5m long and 3m wide. The ceiling is different heights wth about half a meter 20cm higher (above picture windows at one end).

Originally the speakers were on the long wall with a speaker in a corner - even with the Ane's wth their rear port there was a lack of deep bass from that corner which is bloody weird. The Tannoys were the same, hence moving them.

So I've tried the front firing Tannoys in the corners with the picture window behind (used to a have a sub there for movies and it had tons of bass) - firing down the length of the room - no bass at all.


So I've reversed everything wth speakers half way down room firing towards windows and about 3m behind. Some bass but not as much as behind the speakers even though the Tannoys are front firing.

My head is spinning.

[Lerxst]

Yeah, usually it is the worst thing to control. Does it increase and decrease as you move round the room? Pointing the speakers in a different direction doesn't help (just make things asymmetrical)? A little bit further away from the wall to mess up the reflections a bit. What shape is the room? Sounds like some kind of cancellation effect. There are some frequency generators on the internet - you may have a problem with a certain frequency range and something that is absorbing in that range.

I am afraid I am probably suggesting things you have already done. Given the choice I would have the speakers at the long end of the room and listen about 2/3 of the length of the room. So, speakers pointing along the length, not width.

[farflungstar]

Yeah, usually it is the worst thing to control. Does it increase and decrease as you move round the room? Pointing the speakers in a different direction doesn't help (just make things asymmetrical)? A little bit further away from the wall to mess up the reflections a bit. What shape is the room? Sounds like some kind of cancellation effect. There are some frequency generators on the internet - you may have a problem with a certain frequency range and something that is absorbing in that range.

I am afraid I am probably suggesting things you have already done. Given the choice I would have the speakers at the long end of the room and listen about 2/3 of the length of the room. So, speakers pointing along the length, not width.See my post above yours...

[struth]

Some speakers are weird no doubt. Tannoys can be odd for instance. What are the speakers?

I run my speakers down width and it's fine but with tannoys it didn't work

[farflungstar]

Some speakers are weird no doubt. Tannoys can be odd for instance. What are the speakers?

I run my speakers down width and it's fine but with tannoys it didn't workI had problems with the Ane's and now the same issue with the Tannoys - there's a lot to be said for traditional British house construction with their chimney breasts and alcoves!

The only other possibility is to put them firing across width but the opposite wall - and that would be a shit - the wired spurs are on the opposite wall - and moving half a ton of granite table.... and if it didn't make a difference....

I still don't get why turning the balance gives bass....

Oh kensingtons.

[Lerxst]

We crossed lines s bit there. Sorry.

[farflungstar]

We crossed lines s bit there. Sorry.My fault.

[struth]

Need to get a room treatment mike and software. Or get a guy in

[Sherwood]

In the last twenty years I have been fortunate to live in detached houses in different parts of the world. In all cases the main living/listening room was large with high ceilings and solid floors. I never had a problem with hifi positioning and in most cases was able to have the speakers several feet away from the back wall to optimise imaging and minimise early reflection problems. This was in contrast to my experience in the UK with smaller rooms and wooden floors. What you are describing sounds like classic wave cancellation effects. Even though it might not be a long term solution, have you tried bringing your speakers out to around 2/5th's the length of of room and pointed to slightly behind your listening position? I suspect that will confirm my diagnosis!

[RothwellAudio]

How could a room cause bass cancellation - in front but wallops of it behind.....
By producing standing waves, that's how.


Sounds like some kind of cancellation effect.
No, not a weird cancellation effect, just a cancellation effect.


Some speakers are weird no doubt.
Standing waves will occur in a room regardless of the speakers used.


Lots of info here which should explain what's going on.
http://realtraps.com/articles.htm

[walpurgis]

Yes. Reflected waves and localised room resonances can cause cancellation effects.

[Rothchild]

You don't give a ceiling height but guessing in at 2.2m gives you big axial nodes at 45Hz, 57Hz, 68 Hz and 78Hz (and of course a bunch more) so you're going to be getting big peaks and troughs at those frequencies across the room causing all sorts of funny business in the low end.

https://amcoustics.com/tools/amroc?l=750&w=300&h=220&r60=0.6

Speaker / listener position may help, but realistically some significant treatment / trapping at those frequencies is going to do the best job at sorting it out - get some rockwool in the corners.

[Sherwood]

Adrian,

I suspect that you will not find an easy solution to your problems. I am sure that the Tannoys are fine speakers but they are physically large so that it is difficult to position them to fire down the long axis of the room and still keep them away from the side walls. If you were to space the speakers with their centres 2m apart then I'm guessing that they would be less than 1ft from the side walls. I think that you may have to find a solution with the speakers on the long wall.

Room acoustics are a real challenge. My first speakers (Rogers LS3/5a's) demanded some space around them to work properly but were well suited to the smaller rooms I used them in. In those days I was living on flats or in close proximity to neighbours so could not crank up the volume very loud. Listening at low to moderate volume levels helps to mitigate problems with room acoustics anyway. The best room I ever had for hifi was about 12m square with ceilings well over 3m. The floor was concrete will large marble tiles. It might have been a bit lively had it not been for the large amount of damping from heavy drapes, thick jute rugs, big sofas, and lots and lots of cane bookshelves filled with books. The second best room was in a Georgian house in Yorkshire. This was a much smaller room although still squarish in dimensions (I'm guessing around 5m by 6m, with really high ceilings). Most modern houses seem to have elongated lounges which makes the physical placement of equipment challenging let alone the acoustics. That is certainly the case with the lounge in my recently built house which is about 3.5m by 6.5m. I have been fortunate that I could use a double bedroom as a dedicated listening room for my Magneplanar 1.7 speakers. Whilst not ideal, the fact that the Maggies are dipoles with very little side radiation means that they work surprisingly well in a smaller room.

Geoff

[tapid]

And yet many folks say squarish rooms are hardest to work with sonically speaking, just shows there s no set rules for these things.
My speakers firing down a longish narrow room ( wooden floors ) does base very nicely certainly better than my old square listening
room with carpet. Good luck Adrianne with the problem.

[paulf-2007]

It's as easy as room treatment end of. All these discerning listeners in denial, box swapping endlessly, because that's what they like to do.

[tapid]

Sorry made a horlicks of spelling your name. Adrian

[Macca]

I have a similar issue only not so pronounced. I guess you have experimented with moving the speakers forwards and backwards and the listening seat likewise? In along room with speakers firing down the length they reckon you should have the speakers 1 third down and the seat 1 third down the room, or if that doesn't work try 1 fifth. If you didn't already.

[agk]

I'm having trouble getting away from this "The weird thing is if I turn the balance full to either speaker there is loads of bass - but turn it back and it's like they cancel each other out."

[Sherwood]

And yet many folks say squarish rooms are hardest to work with sonically speaking, just shows there s no set rules for these things.
My speakers firing down a longish narrow room ( wooden floors ) does base very nicely certainly better than my old square listening
room with carpet. Good luck Adrianne with the problem.

I guess perfectly square rooms may pose some problems but the rooms are was referring to were "squarish"!

Geoff

[farflungstar]

I'm having trouble getting away from this "The weird thing is if I turn the balance full to either speaker there is loads of bass - but turn it back and it's like they cancel each other out."Having done a lot of reading on room acoustics this could be explained by reflections causing the cancellation. In theory.

Today is a rare day off so I'm going to continue experimenting

[walpurgis]

Just hanging a wall rug could be all you need.

Damping of rooms is a strange thing. You never know what may work.

[tapid]

I have a similar issue only not so pronounced. I guess you have experimented with moving the speakers forwards and backwards and the listening seat likewise? In along room with speakers firing down the length they reckon you should have the speakers 1 third down and the seat 1 third down the room, or if that doesn't work try 1 fifth. If you didn't already.

Yeah, the third/ third route works well in my narrow room.

[tapid]

I have a similar issue only not so pronounced. I guess you have experimented with moving the speakers forwards and backwards and the listening seat likewise? In along room with speakers firing down the length they reckon you should have the speakers 1 third down and the seat 1 third down the room, or if that doesn't work try 1 fifth. If you didn't already.

Yeah, the third/ third route works well in my narrow room.

[struth]

duvets are also good as a temp trial to find spots needing treatment

[agk]

That line I quoted sounds like a textbook example of a phase problem somewhere.
I just don't trust coincidence is all.

[RothwellAudio]

Just hanging a wall rug could be all you need.


duvets are also good as a temp trial to find spots needing treatment

Absorbing high frequencies is quite easy. Absorbing bass frequencies is something else entirely. A duvet or an inch of rockwool isn't going to do anything for frequencies below 100Hz.

[struth]

scrunched up duvet on top of back of chair will affect it enough to find the area requiring attention, as might a thick rug.

[Spectral Morn]

Let me guess, typical Spanish wall construction, hard tiled floor and bare walls.

A photo of the room would help those commenting.

[farflungstar]

I'm in the middle of putting things back to speakers firing across the narrow room not down it. I've out I rolled up rug in the corner on the weak bass side. Will put a pic when it's back in I've piece!

[farflungstar]

This is with them firing across the room - the weak bass is the one near the window. https://uploads.tapatalk-cdn.com/20171009/4b8d1b2d22d03a6112da082bcab37337.jpg

[struth]

looks very busy over that side. something might be requiring moved. maybe a much bigger toe-in too as window is there

[farflungstar]

I need to move!

[Spectral Morn]

As I thought, typical Spanish room. So its going to be a pretty live acoustic without the stuff in it. Walls are not the most solid and reflective as is the floor and ceiling. Narrow doesn't help either. I would be inclined to try firing down the room, but that does mean a trade off of some issues for others.

The floor rug looks thin, a thicker heavier rug would be better.

[Spectral Morn]

I need to move!

Spanish buildings are pretty typical all over so you might get a bigger room but still have a very live acoustic.

[farflungstar]

As I thought, typical Spanish room. So its going to be a pretty live acoustic without the stuff in it. Walls are not the most solid and reflective as is the floor and ceiling. Narrow doesn't help either. I would be inclined to try firing down the room, but that does mean a trade off of some issues for others.

The floor rug looks thin, a thicker heavier rug would be better.The problem is worse when firing down the room especially from the window - I've tried a thicker rug.

Firing across bass is full on the left but almost non existent below 50hz on the window b side - its reflecting from something at 180° and so out of phase. I'll try covering everything that side.

[farflungstar]

Spanish buildings are pretty typical all over so you might get a bigger room but still have a very live acoustic.I dont mind that - I have so much furniture and stuff filing a space is easy!
It's such a bitch as I'd bought a lovely leather listening chair thinking I would be listening down the length of the room. Grrrr

[struth]

i would try moving the far speaker in front of the unit away from window temp and see if it comes back

[agk]

Lovely room and kit, get you a gallery thread please.

Have you listened with the windows open and closed, any variation in bass?
Aside from that I think the window is killing the bass on that side.
Oh and the speakers look quite far apart in relation to your listening position.

[Spectral Morn]

The problem is worse when firing down the room especially from the window - I've tried a thicker rug.

Firing across bass is full on the left but almost non existent below 50hz on the window b side - its reflecting from something at 180° and so out of phase. I'll try covering everything that side.

Ahh ok a bass suck out due to the difference in depth to the side and the window. Install heavy curtains, that might work.

Have you tried moving whatever that plant is sitting on out of there ? Maybe move the TV back further into the bay window. Other option strip the window area and see how it sounds with nothing there and put stuff back in until it goes off again, at least then you know what it is that is causing the issue.

I will say its all very cramped, not a lot of space around the speakers.

[farflungstar]

I've tried just about everything today with no real difference, including blankets and duvets all over the place. Beginning to think maybe im deaf to very low frequencies in one ear but if thats true i never notice it in daily life or when listening to other set ups. I've been testing in mono. Not a happy bunny.

[Spectral Morn]

I've tried just about everything today with no real difference, including blankets and duvets all over the place. Beginning to think maybe im deaf to very low frequencies in one ear but if thats true i never notice it in daily life or when listening to other set ups. I've been testing in mono. Not a happy bunny.

With more space to one side of a speaker than the other you may end up with a lopsided soundstage, or frequency issues. Its hard to tell or sort without being in the room. Sorry.

[Macca]

Those things won't make the slightest bit to difference to the bass response.

If I were you I'd clear everything out of the room and start from scratch. It is highly unlikely that the room has no spot in which the speakers will sound balanced.

Probably not what you want to hear though.

[Spectral Morn]

Those things won't make the slightest bit to difference to the bass response.

If I were you I'd clear everything out of the room and start from scratch. It is highly unlikely that the room has no spot in which the speakers will sound balanced.

Probably not what you want to hear though.

I think stripping back to bare bones is the only option, then put extraneous furnishing back in until it goes wrong, then remove again, is the only way.

[struth]

I take it youve swapped speakers and swapped outputs, switched cables just in case its electronic

[farflungstar]

I take it youve swapped speakers and swapped outputs just in case its electronicYup, cart outpuput, Vida output, truth output, amp input... The same...

After struggling with the same problem wth the Ane's which are rear ported I finally fixed it by putting cushions on the side wall behind the weak one - balanced or at least better. I can't do that wth the Tannoys though I've tried... hmmmm

[struth]

have you moved the weak one into the room? being closer together will help too. they are a fair spread considering your sitting so close so might help a bit. I usually do an equilateral triangle with either to in or out.
I had a bad connection on one speaker that was causing mine once.

[farflungstar]

I think the photo is misleading they are more be or less equidistant. Yes bringing the speaker in helps - but having it a foot further into the room doesn't help with imaging lol

[Spectral Morn]

I think the photo is misleading they are more be or less equidistant. Yes bringing the speaker in helps - but having it a foot further into the room doesn't help with imaging lol

That's what I was hinting at regarding trade offs....

[struth]

well that kinda confirms its the window. you need some smart way of taking it out of the equation. have you tried sitting in the window with it coming down toward you. some heavy double curtains and the couch might then help give a soft wall like stop. dare say the units could stay and just used long cable

[RothwellAudio]

Have you listened with the windows open and closed, any variation in bass?
That's certainly worth trying. A hole in a boundary is the ultimate absorber - you can't get reflections if there's nothing there! Having said that, the lower the frequency the bigger the hole needs to be to be effective.

... Install heavy curtains, that might work.

I've tried just about everything today with no real difference, including blankets and duvets all over the place.

Those things won't make the slightest bit to difference to the bass response.
Macca is right - blankets and duvets won't do anything to touch bass frequencies, nor will heavy curtains. However, blankets/duvets rolled up like a roll of carpet and placed in the corners of the room might be more effective as a bass trap.

[farflungstar]

Yes I tried sitting in the window with the speakers firing down. Balanced but reduced both sides - weird as the 'good' speaker hadn't really changed position apart from angle. Another problem with this bloody flat is the walls are not parallel - they flare by about 15cms aside - oh for an old Georgian house!

[RothwellAudio]

Another problem with this bloody flat is the walls are not parallel - they flare by about 15cms aside - oh for an old Georgian house!
Non-parallel walls are good! Unfortunately (again), they have to be way off parallel to affect bass frequencies. Still, they're probably effective at high frequencies and should reduce flutter echo.

[farflungstar]

Well I've tweaked until I can tweak no more. I tried the windows open - no difference. I don't get it. On some albums no problem - equal - but on other albums, for example Diana Krall double bass is plucked centre stage but the body of the notes come from the left. All other imaging is rock solid and sounds great.

[Spectral Morn]

Well I've tweaked until I can tweak no more. I tried the windows open - no difference. I don't get it. On some albums no problem - equal - but on other albums, for example Diana Krall double bass is plucked centre stage but the body of the notes come from the left. All other imaging is rock solid and sounds great.

Is there an open archway to the left of the speakers, or a solid wall ?

[farflungstar]

That's where it's complicated.....

There's a spiral staircase going to an enclosed glass conservatory, there's a small open plan kitchen and after that a long long corridor.

[Macca]

Well I've tweaked until I can tweak no more. I tried the windows open - no difference. I don't get it. On some albums no problem - equal - but on other albums, for example Diana Krall double bass is plucked centre stage but the body of the notes come from the left. All other imaging is rock solid and sounds great.

That could be the recording. Your system is just revealing some manipulation by the engineer. If it isn't a problem on some recordings, as you say, that pretty much rules out a room effect as the culprit.

[walpurgis]

That could be the recording. Your system is just revealing some manipulation by the engineer. If it isn't a problem on some recordings, as you say, that pretty much rules out a room effect as the culprit.

I agree. Bass can be biased to one side on some recordings.

[farflungstar]

I agree but it's almost always on the left...

[farflungstar]

Okay so I got out some string and to the mm positioned the speakers to cross just in front of me as per Tannoys instructions - I cant believe a few CMS can make such a bloody difference - but it has - bass much more balanced - still a little off centre wth some recordings but way way better.

[Rothchild]

Having done a lot of reading on room acoustics this could be explained by reflections causing the cancellation. In theory.

Today is a rare day off so I'm going to continue experimenting

Lol, I'll guess my response got phase cancelled.

Acoustics (at least at this basic level) is not really theory, it's all pretty well worked out. Two waves coinciding 180 degrees opposite to each other will cancel (1 - 1 = 0) waves colliding 'in sync' will amplify (1 + 1 =2) Which waves cancel and which waves amplify is simply a function of the wave length (frequency) and the distance between the reflecting surfaces (room size).

But you might want to try some diifferent interconnects / speaker cables too?

[hayche]

Glass is VERY reflective so it will cause more bass nulls than normal.
You should try a different room if you can. You also need equal distances to your side walls.
Try the rule of thirds if that is possible. Have your speakers 1/3 the distance of your side walls apart. Also if you can 1/3 the distance from your front wall and sit 1/3 away from your back wall.
I take it you have sat right on the back wall to check for bass in your current set up? Bass does tend to hang around the boundaries when they are not out in the room.

[RothwellAudio]

Glass is VERY reflective so it will cause more bass nulls than normal.
Indeed, glass is very reflective and is a superb reflector at high frequencies. However, if it's single-glazed it also has some give in it and therefore is less effective as a reflector at low frequencies.

[RothwellAudio]

BTW, there's another possible explanation as to what's going on here. Instruments like double basses have very week fundamentals and the ear picks up a lot of information from the higher harmonics. That's means that an anomaly in your room higher up the frequency spectrum may appear to be a bass frequency issue.

[farflungstar]

This might explain why even when switched to mono there is some difference between channels. I really do need to move house I think.

[GrahamS]

Sounds like standing wave cancellation due to opposing wall reflection. The wall opposite the speakers needs to be softened with curtains, tapestries and furnishings. I once hung a Chinese carpet on the wall.

[anthonyTD]

I have a small carpet on the one wall of my listening room too.:)
Sounds like standing wave cancellation due to opposing wall reflection. The wall opposite the speakers needs to be softened with curtains, tapestries and furnishings. I once hung a Chinese carpet on the wall.

[struth]

Ive got a big mirror :eek:

[anthonyTD]

One thing I will say;
When someone has spent most of their hi fi years listening to conventional, multi-driver speaker enclosures,[that includes me] it can be a bit of a shock when first hearing a good dual concentric driver system, and sometimes' as others here have said; it can be a bit off putting as recordings you thought you knew can sound quite alien to start with, once you get them set up correctly[or the best your room will allow] you will become more familiar with those recordings again, but perhaps in a more intermit way, as you will no doubt hear things more accurately, and more precisely placed within the recording.
Therefore; there will be many recordings that you thought were well recorded, that dont sound perhaps as good as you remember, but on the other hand, there will be others that will blow you away!
Swings and roundabouts, unfortunetly like everything in life, nothing is perfect.:)
A...

[RothwellAudio]

Sounds like standing wave cancellation due to opposing wall reflection. The wall opposite the speakers needs to be softened with curtains, tapestries and furnishings. I once hung a Chinese carpet on the wall.

I'm going to say this one more time in the hope that the message gets through: curtains/tapestries/blankets etc. have no effect at bass frequencies. Yes, above about 1kHz there will be some absorption which will help imaging etc. but bass frequencies are not affected by curtains.

[anthonyTD]

I think most here understand where your coming from, and agree Andrew, however; as with many situations in Audio, sometimes there are other reasons why the OP is experiencing what he seems to be, and that is why folk here are offering ideas that might alter the situation for better or worse.:)
I'm going to say this one more time in the hope that the message gets through: curtains/tapestries/blankets etc. have no effect at bass frequencies. Yes, above about 1kHz there will be some absorption which will help imaging etc. but bass frequencies are not affected by curtains.

[struth]

Indeed.... Sometimes altering the high freq can change the perception of the low.

[RothwellAudio]

I think most here understand where your coming from, and agree Andrew...
Ye, perhaps I should take a chill pill ;)

[anthonyTD]

:eek::D
Ye, perhaps I should take a chill pill ;)

[Pigmy Pony]

Another suggestion: fit some bi-fold doors along one wall, open them up, and let the bass bounce off your neighbours house. Worth a try.