Unwanted Resonances

[The Grand Wazoo]

This is not a criticism of anyone at all, more like an observation and a tale of my take on things.

Let's imagine that you've just discovered that an easily portable and non essential item made of steel in your listening room is measurably and visibly vibrating in sympathy with the sound coming from your speakers, and that if you listen carefully from close up, you can hear a ringing noise coming from it,
What would you do?


Would you remove the item in question?
Would you damp it, in order to reduce the impact on the sound you hear – whether you think you can hear its contribution under normal listening conditions or not?
Would you just forget about it because you can't detect it when the music's playing anyway?


Now then, what if there were six of these items combining to create a bigger sound?



I notice from Gallery photos etc that quite a few members of AoS have guitars in their listening rooms. This is understandable as most people use their rooms for more than just listening, and we all love music, right? – Not only that, but a good guitar is a thing of beauty, so it's no wonder you'd want to have it on display and to hand for when the mood to play takes you.

However, guitar strings sing along with the hi-fi as I've described above & though that sound can be pleasant, it ain't what's on the recording! Acoustic guitars are louder culprits, but less tinny sounding that electrics.

So, if you have a guitar in your room, do you damp the strings or do you remove it for critical listening?

We have 3 guitars in our house – a beautiful acoustic 9-string, a semi-acoustic and a Strat copy – as well as a cello. That's 25 strings, each wobbling away, putting additional sound energy into the room & ruining the sound of the hi-fi. - Well, I suppose that's rather an overstatement, but you hopefully see where I'm coming from.

As it happens, we keep the instruments in a separate place & always have, but I have a system in there too & it's very clear that a good sneeze, for example, sets off the strings of the acoustic & you can hear the output if there's no music playing. In our last house we had the guitars hanging on the wall & kept things damped with little strips of paper folded up & interleaved between the strings (maybe they should have morphic-mojo messages on them!). The cello always stays in its case unless it's being played.

I'm just interested in whether others consider it may be a problem? If so, do they do anything about it? Or whether, in fact, they've even thought about it before?

[DanJennings]

never even thought about it....
in my old room I had 4 guitars, a bass, and two violins.... never heard a peep out of them.

[Stratmangler]

I too thought about resonances being a potential problem when I saw this (http://theartofsound.net/forum/showpost.php?p=75529&postcount=5) post.

Strat being between the speakers an' all that.

Chris:)

[The Grand Wazoo]

Yeah Chris,
It was that photo that made me post the above, but it's been in the back of my mind for ages.

[Themis]

I thought I read somewhere* that our brain "dismissed" somehow small irregularities between left and right side sounds (differences between each ear).
So, even if the room (or its contents, if you prefer) causes obvious frequency imbalances, the listener adapts its listening to them. In a similar way, we don't pay attention to continuous background noise (of 40dB or so), we simply dismiss it from the overall sound and we keep only what we need to pay attention to.

This is to say, that, even if several resonances exist, and even if they can produce a *combined* measurable (or audible) effect, it still doesn't mean that such an effect actually modifies our perception of the reproduced music.

* There, in fact: http://www.ethanwiner.com/believe.html

[Marc B]

I seriously doubt you will be able to hear guitar strings resonate with your music.

The main sound from a guitar is the pluck, the rest of the sound decays quite quickly. The tiny string just wouldn't have the energy to be audible. If you can see your strings vibrate then you may be able to hear it - but you'd have to have your hifi on at deafening levels in order for that to happen.

Your couch, windows, rack, tv etc will resonate a lot louder than any guitar string.

[Marco]

...And so will any ornaments you have lying around, or anything else that rattles, hence why my system resides in a room upstairs and not in my antique/bric-a-brac-laden lounge.

Russ Andrews coined a phrase for it (which escapes me now), but basically it was to do with everything that's in your room, and not fixed down in some way, 'singing along', due to the vibration created from your speakers when playing music.

He suggested that all 'offending' objects should be, for example, Blu-tacked down or removed from the room and put elsewhere. I tried this once and it definitely improved the sound. It's one of the reasons why I keep my listening room free of as much clutter as possible :)

Marco.

[The Grand Wazoo]

I seriously doubt you will be able to hear guitar strings resonate with your music.

The main sound from a guitar is the pluck, the rest of the sound decays quite quickly. The tiny string just wouldn't have the energy to be audible. If you can see your strings vibrate then you may be able to hear it - but you'd have to have your hifi on at deafening levels in order for that to happen.

Your couch, windows, rack, tv etc will resonate a lot louder than any guitar string.

Well, with my wife's acoustic guitar on the wall in our last house, you could hear it when people spoke at anything above a normal volume, or sneezed or coughed - hence the reason for my damping the strings - not for any hi-fi reason, it was just bloody annoying. It didn't need anything to be at deafening levels. Admittedly the room was a little live sounding.

If my couch, windows, rack, tv etc resonated as loud as that when someone spoke, I'd chuck 'em out & I bet you would too.

I'm not suggesting that you might hear it above the sound of the system in the sense that you can pick out the noise, but if it's there, it can't be helping, can it?

Marco,
The effect that RA was describing is slightly akin, I suppose, to the 'terroir' of the wine world!

He suggested minimising the effect by nailing down or removing rattly objects - that's exactly what I'm alluding to. I've never done any comparisons with & without half an orchestral string section in the room with me, but my feeling is that it must be compromising things slightly.

[Marco]

He suggested minimising the effect by nailing down or removing rattly objects - that's exactly what I'm alluding to. I've never done any comparisons with & without half an orchestral string section in the room with me, but my feeling is that it must be compromising things slightly.


Hi Chris,

Trust me, if you can be arsed doing it, it works! Anything that removes 'noise' from the environment a hi-fi system operates in has to be good :)

Marco.

[The Grand Wazoo]

Hi Chris,

Trust me, if you can be arsed doing it, it works! Anything that removes 'noise' from the environment a hi-fi system operates in has to be good :)

Marco.

Speak up a bit, I can't hear you above the sofa!
I don't need convincing, mate, but it seems like others may!

[Marc B]

Well, with my wife's acoustic guitar on the wall in our last house, you could hear it when people spoke at anything above a normal volume, or sneezed or coughed - hence the reason for my damping the strings - not for any hi-fi reason, it was just bloody annoying. It didn't need anything to be at deafening levels. Admittedly the room was a little live sounding.

If my couch, windows, rack, tv etc resonated as loud as that when someone spoke, I'd chuck 'em out & I bet you would too.

I'm not suggesting that you might hear it above the sound of the system in the sense that you can pick out the noise, but if it's there, it can't be helping, can it?

Marco,
The effect that RA was describing is slightly akin, I suppose, to the 'terroir' of the wine world!

He suggested minimising the effect by nailing down or removing rattly objects - that's exactly what I'm alluding to. I've never done any comparisons with & without half an orchestral string section in the room with me, but my feeling is that it must be compromising things slightly.

What you have is probably a flutter echo. When the sound frequency matches the distance between the 2 walls you will get a ringing sound. This "might" excite the acoustic guitars body, which may rattle strings if it's a similar frequency but it's more down to the empty spaces on the walls than the actual guitars.

I bought 10x GIK panels to get rid of mine.

[The Grand Wazoo]

Call it what you want - the guitar strings made a noise.
So, should I remove the guitar or the walls?
I chose (in effect) to remove the guitar - I hope that was the right thing to do!

[Themis]

I chose (in effect) to remove the guitar - I hope that was the right thing to do!
Did you notice any change ? It would be nice to know. ;)

[The Grand Wazoo]

Did you notice any change ? It would be nice to know. ;)

Well, as I said earlier, I don't keep guitars in the same room as the main hi-fi, so a change wouldn't have been spotted if it happened. I deadened the strings to stop an annoying noise rather than to change how an audio system sounded.

I'm not really in a position to try it in our new house because I'm still messing about with things in a new room but I'm be interested to hear what others think or have found (hence the original post).

Cheers!

[Barry]

This is a very interesting thread – and I’m not sure where I stand. Like most people my listening room is also the living room, and as such is full of books and bric-a-brac garnered from my travels. There are also several framed, glass-fronted, watercolours hanging on the walls. One day I will supply some photographs – something I said that I would do, shortly after joining AoS. Be patient!

None of this has been noted as resonating or ‘obviously’ adding to the room’s acoustic. Of course it must do, but I say I’ve not noticed any vase, pot or hanging object resonating. Having said that, I have wondered if some of the tubular steel equipment racks available are such a good idea, unless the hollow tubes are filled with, say, silver sand (I believe this was discussed in another thread). Certainly some of the room treatment devices, such as bass traps, do work on this principle (that of the Helmholtz resonator).

On balance, if there were an item in the listening room that was obviously resonating and doing so in a distracting fashion, then I would try to dampen the resonance in the first instance. If that did not work then I would remove it from the room. I don’t think I would go as far as having the system in a Spartan environment advocated by Marco.

Is this a general speculation Chris, or is it an unwanted side effect of your ‘new’ ears?

[Marco]

Hi Barry,

I completely understand what you're saying. However:


On balance, if there were an item in the listening room that was obviously resonating and doing so in a distracting fashion, then I would try to dampen the resonance in the first instance. If that did not work then I would remove it from the room. I don’t think I would go as far as having the system in a Spartan environment advocated by Marco.


You must have seen pictures of my room; it's hardly spartan! :)

It's got everything I need in there to make it a comfortable and pleasant place to be - *BUT* without the superfluous 'clutter' (or rather other possessions which are dear to me) that live in the downstairs lounge.

This is one of the advantages of having a dedicated listening room (one can optimise things purely in terms of how the system performs), which I realise is not possible for everyone.


None of this has been noted as resonating or ‘obviously’ adding to the room’s acoustic. Of course it must do, but I say I’ve not noticed any vase, pot or hanging object resonating.

On balance, if there were an item in the listening room that was obviously resonating and doing so in a distracting fashion, then I would try to dampen the resonance in the first instance.


Yes, but you're missing the point matey... It's not about resonances so obvious that they're easily heard under normal circumstances; it's about those which aren't 'heard', yet insidiously impose their sonic signature on the sound reproduced by your system, creating their own form of distortion, and adversely affecting how your system reproduces music in the process.

Trust me, when you remove the resonant effect of the items concerned, the improvement in the sound of your system is obvious.

However, let's return to the real world. Homes are for living in, and so a hi-fi system more often than not has to share available space with your other possessions. A comfortable and inviting listening environment is far more important than creating some stripped-back, spartan, domicile in order to maximise sound quality.

That doesn't mean though that if it’s possible to have both that the benefits aren't noticeable and worth having :cool:

Marco.

[Macca]

I have two guitars in my living room but they are both solid body electric (a Les Paul copy and a Tele copy, both covered, embarrasingly, in dust, as I never play them any more) and I have wondered about this - but I think it is pretty obvious that a hollow-bodied guitar will make some contribution of its own, whereas strings vibrating microscopically on a solid plank of wood ? - No.

Agree with the principle of keeping the listening room as clutter free as possible. It can't hurt and logically should be of some benefit - some things we appreciate sub conciously I think.

[The Grand Wazoo]

Is this a general speculation Chris, or is it an unwanted side effect of your ‘new’ ears?

It's general speculation based on observations from photos of others gear but informed by my own experience of having guitars & cellos lying around the house.

I've never been able to identify a definite problem because the instruments are in another room. Because I felt I had to damp the strings (and this is years ago) to remove an annoying sound produced just when people were speaking, it made me wonder what the effect would be for people who kept their guitars in the same room as their speakers. It absolutely must be having some influence on what you hear from your speakers, whether you recognise it or not, is irrelevant.

I've even seen photos (not on here) of drumkits in the same room as hi-fi speakers - imagine what sort of effect a snare drum would have on what you're hearing!!

[Spectral Morn]

Well as I have a home cinema system at the end of the same room my main system lives in, thats me stuffed. One pair of speakers in a room at once rule....I have about 11 extra in the room....:lol::lol::lol::lol: Never mind all the other bits and bobs.

All those items more than likely do effect the movement of air in the room but whos to say that in some cases it might not lead to a better sound. This is heading slightly down the road of Frank Chang's resonators and Shakti wooden up right jobies (can't remember what they are called).

Frank Chang believes that all the molecules in the air are interlinked, even between rooms....on a molecular level I suppose that may well be correct, and the presence of his tuners may well effect the sound. I have never played with any nor the Shakti stuff either way to weird for me. However the layout of items in your room does change the acoustics for better or worse and items that resonate will too. IMHO if you don't have a dedicated room then really all you can do is remove anything that resonates loudly enough to annoy you....everything else just has to stay.


Regards D S D L

[Joe]

I have an acoustic guitar leaning right up against a speaker and it doesn't resonate as far as I'm aware.

[Alex_UK]

Yes, but you're missing the point matey... It's not about resonances so obvious that they're easily heard under normal circumstances; it's about those which aren't 'heard', yet insidiously impose their sonic signature on the sound reproduced by your system, creating their own form of distortion, and adversely affecting how your system reproduces music in the process.

MG, all that talk of horror films the other day - the bodysnatchers have landed and Marco has been replaced by a Beltist! :lol:

Take off a sock!

[Mike Reed]

...And so will any ornaments you have lying around, or anything else that rattles, hence why my system resides in a room upstairs and not in my antique/bric-a-brac-laden lounge.

Marco.

Normal remedial action would be to remove the offending objects. Marco's is to remove the hifi.

That's gotta be lateral thinking ! Or in his case, I believe, Vertical!

[Alex_UK]

Very good Mike! That made me laugh! A lot! :lol::lol::lol::lol::lol::lol:

:D :D :D :D :D :D :D :D

[The Grand Wazoo]

Normal remedial action would be to remove the offending objects. Marco's is to remove the hifi.

That's gotta be lateral thinking ! Or in his case, I believe, Vertical!

Well that's not so wacky when you consider it's already been implied that removing the walls would be a good thing!

[Marco]

LOL - what are you guys like? :ner:

Having my system downstairs in the lounge is a total non-starter, and was never in the equation, as there just isn't room for it *and* all the antiques, Welsh dresser, etc... So down there the latter takes priority, as my system (and the huge speakers) would definitely spoil the period ambience of the room.

I do know though, however, from experience that all the ornaments in the display cabinets and the plates on the dresser, not to mention all manner of other 'clutter', would cause the type of resonance being discussed here and adversely affect the sound of the system as a result - hence also why the system resides where it does! :)

Marco.

[Marc B]

Well that's not so wacky when you consider it's already been implied that removing the walls would be a good thing!

Nobody implied you remove the walls? (or I didn't anyway)

I said that you have what is called a flutter echo. To get rid of it you place an object between them to diffuse or absorb soundwaves so they can't ping-pong between two parallel walls.

[Mike Reed]

There's only one foolproof solution here; remove the speakers to the lawn outside.

MAGIC !!!!!! (sonically)

Unfortunately the magic wears off with the climate.

Romove the walls, eh? Just make sure you live in a bungalow or there'd be an enormous floor (!!!???!!!) to that course of action.

[Themis]

Some people would be disappointed if they listened to their speakers outside... The sound is not always for the better. Walls may actually help. ;)

[The Grand Wazoo]

Nobody implied you remove the walls? (or I didn't anyway)

I said that you have what is called a flutter echo. To get rid of it you place an object between them to diffuse or absorb soundwaves so they can't ping-pong between two parallel walls.


I know Marc...........it was a joke

[Mike Reed]

Some people would be disappointed if they listened to their speakers outside... The sound is not always for the better. Walls may actually help. ;)


Yes, you are quite right, Dimitri; I believe it depends upon the type of speaker.

For example, my little Rogers LS6 I.B. speakers really sang on all the lawns I've played them in, but Isobariks? Oh, no! 'orrible, presumably because of upward-firing tweeters. SBLs were so-so, but had to be backed against the house wall, of course.

My rear-ported ProAc 3s and 3.5s sounded like an orchestra (or band) in the park; quite wonderful!

'Orses for courses, I feel, but when a speaker does gel with the great wide open, the result is pure magic.

Electrostatics? Horns? Oddball hybrids? Wouldn't even hazard a guess !

[Macca]

Outdoor gigs are never as good as indoor for sound - everything being equal -
and that's just a very big, horn loaded, hi-fi you are listening to.

I love the attention to detail - ('I know - I'm going to test all my 'speakers outside!')