Loudspeakers: spikes or decoupling?

[johnb]

I feel a bit daft posting this, but here goes:

A few weeks ago, while browsing audio topics, I came across discussions about and praise of the Townshend Podium (££££), Townshend Seismic Bars (£££ for those in poverty) and the IsoAcoustics Gaia feet (££). They "work" by decoupling the speaker from the floor. (Townshend seem to target the audiophile crew but IsoAcoustics make pro-audio stuff.)

I always thought that metal spikes under loudspeakers were de rigueur but I was curious. Squash balls are cheap so I decided to see what would happen with them.

I removed the spikes and replaced each of them with half a squash ball. The squash balls were ... err ... pretty well squashed but the loudspeakers still wobbled when touched - not excessively though.

Alas I am missing those "golden ears" so usually when I try something out (e.g. interconnect leads) I often (not not always) hear very little if any difference. But in this case I was surprised by how the stereo image and the instruments all seemed so much more sharply defined. This is inline with the discussions about the Townshend and IsoAcoustics products that I had read. (Whether my perceptions matched the reality is another matter.)

A bit of background:
My speakers are floor standing, quite heavy (approx 21kg each) and approx 1m tall. The room has a wooden suspended floor. I normally use spikes which rest on a granite "chopping board" (c/o Argos). Under each of the granite slabs there are 4 small blobs of BluTack to make sure they are "solid".

It might be that this type of decoupling would have a negative effect with less heavy speakers (i.e. which have less inertia) and/or with speakers spiked to solid floors.

All this sounds like the sort of dubious "magic" that you read about in audiophile forums, but I thought I would post it anyway.

[Ian_of_glos]

My speakers are on spikes to minimise sympathetic vibrations coming through the floor. They work well but I have not found the need to use blue tack as well.
I have never tried using squash balls although I expect the principle is the same.

[MrGongGong]

Rubber bungs/squash balls all will work if you have a suspended floor
I'm sure the folks at Russ Andrews will have some organic rubber specially treated by aligning its chakras by moonlight and individually hand turned by virgins that you can buy for a mere £1,000 per set of 4

Physics innit

[Dave2002]

Rubber bungs/squash balls all will work if you have a suspended floor
I'm sure the folks at Russ Andrews will have some organic rubber specially treated by aligning its chakras by moonlight and individually hand turned by virgins that you can buy for a mere £1,000 per set of 4

That’s only for the bronze edition, the platinums are £5k per ball.

Or you can buy a grounding box.

I’m slightly surprised by msg 1, but not dismissing it. If the squash balls work, then fine. Elsewhere some people are experimenting with dehumidifiers, some claiming sonic improvements, and some not.

[johnb]

Rubber bungs/squash balls all will work if you have a suspended floor
I'm sure the folks at Russ Andrews will have some organic rubber specially treated by aligning its chakras by moonlight and individually hand turned by virgins that you can buy for a mere £1,000 per set of 4

Physics innit

Thanks for that reassurance. As for £1,000 at Russ Andrews - that can't be any good, much too cheap. You need the Townshend Podium at least (price £1,400 to £3,900 depending on size).

I’m slightly surprised by msg 1, but not dismissing it. If the squash balls work, then fine. Elsewhere some people are experimenting with dehumidifiers, some claiming sonic improvements, and some not.

Dave, the possible reasoning (as I see it) is that when a loudspeaker is firmly coupled to a (lively) suspended wooden floor, e.g. using spikes, the loudspeaker also drives vibrations in the floor, albeit at a low level. These then vibrations also feed back into the speaker cabinet, affecting (to what ever degree) the speaker output. Decoupling the speaker from the suspended floor stops that happening.

Of course, when decoupled like that, the loudspeaker is no longer rigidly positioned and the argument for spikes has been that the speaker cabinet should be absolutely static to enable the speaker drivers to do their job. My speakers are quite heavy (~21 kg each) and I'm guessing that they have a high enough inertia to be less affected by speaker cone/air movements than relatively light (in weight) speakers would be. In my case the beneficial effect of the decoupling seems to outweigh any adverse effect due to the speakers being a bit wobbly.

[Bryn]

I just have carpet squares both under and over 18" x 18" concrete paving slabs upon top of which I place the spikes on the bottom of my speaker columns. I'm happy enough with that.

[jayne lee wilson]

Rubber bungs/squash balls all will work if you have a suspended floor
I'm sure the folks at Russ Andrews will have some organic rubber specially treated by aligning its chakras by moonlight and individually hand turned by virgins that you can buy for a mere £1,000 per set of 4

Physics innit

RA major on lightweight wooden supports, to drain vibrational energy out of equipment resting upon it. I use their Oak Cone feet extensively, for 20 or 30 quid per 3 or 4 depending on size....their Torlyte platforms (lightweight but very strong wooden honeycombs) work on a similar principle...
(RA are very down on rubber feet!)

The decision to make is whether to try to contain vibration through mass, or let it out quickly to drain into the most massive parts of the room (usually the floor)..
With the designs themselves, e.g. ATC Speakers go for mass (try picking one up), Harbeth for thin-walled, screwed rather than glued together, rapid release of vibration....(this design principle followed BBC Monitor research years ago, vide LS 3/5A etc)... so for a Harbeth (e.g. my C7IIes) you'd go for spikes (points down...!) plus lighter-weight or part-filled stands to get the energy out of the cabinet quickly.

"Isolation" is possible but soft feet aren't very good at it....they may act as a partial barrier to floor-borne vibration, but airborne energy (from speakers, transports etc) can stay in the component. "Floating" equipment can be better, usually with opposing magnets attached to, say, perspex platforms....(perspex has a very low resonant frequency similar to some types of wood...)...but there's still the airborne vibe problem - wooden feet may help here...
(Stereophile once used an accelerometer to measure the effectiveness of some of these designs, they did pretty well...)

It is as ever down to choices.... consistency is best from a scientific viewpoint but you may still wish to tune the system by ear and mix the various possible approaches....

But very broadly speaking: the lighter the source component/loudspeaker: the more you may want to couple - to drain.
The heavier: isolation - mass - rigidity - might work better.... (it can be self-defeating for very obvious reasons...!)
But let your ears be the guide, as ever...(& try to work out how vibrational energy travels around your own room...)

[Richard Barrett]

My speakers are of the Glaswegian variety and I've had them for about 20 years. When I did my last international move six years ago one of the spikes went missing, and since then they've just been sitting on a parquet floor on their granite/polymer bases which brings their weight to about 28kg each and I don't notice any difference (apart from their being in a different room of course), so I'm inclined to think there's a lot of smoke and mirrors going on with speaker stands etc. (not to mention cables!).

[Stanfordian]

I feel a bit daft posting this, but here goes:

A few weeks ago, while browsing audio topics, I came across discussions about and praise of the Townshend Podium (££££), Townshend Seismic Bars (£££ for those in poverty) and the IsoAcoustics Gaia feet (££). They "work" by decoupling the speaker from the floor. (Townshend seem to target the audiophile crew but IsoAcoustics make pro-audio stuff.)

I always thought that metal spikes under loudspeakers were de rigueur but I was curious. Squash balls are cheap so I decided to see what would happen with them.

I removed the spikes and replaced each of them with half a squash ball. The squash balls were ... err ... pretty well squashed but the loudspeakers still wobbled when touched - not excessively though.

Alas I am missing those "golden ears" so usually when I try something out (e.g. interconnect leads) I often (not not always) hear very little if any difference. But in this case I was surprised by how the stereo image and the instruments all seemed so much more sharply defined. This is inline with the discussions about the Townshend and IsoAcoustics products that I had read. (Whether my perceptions matched the reality is another matter.)

A bit of background:
My speakers are floor standing, quite heavy (approx 21kg each) and approx 1m tall. The room has a wooden suspended floor. I normally use spikes which rest on a granite "chopping board" (c/o Argos). Under each of the granite slabs there are 4 small blobs of BluTack to make sure they are "solid".

It might be that this type of decoupling would have a negative effect with less heavy speakers (i.e. which have less inertia) and/or with speakers spiked to solid floors.

All this sounds like the sort of dubious "magic" that you read about in audiophile forums, but I thought I would post it anyway.

My Wharfdale speakers are designed to be filled about half way with sand.

[richardfinegold]

I feel a bit daft posting this, but here goes:

A few weeks ago, while browsing audio topics, I came across discussions about and praise of the Townshend Podium (££££), Townshend Seismic Bars (£££ for those in poverty) and the IsoAcoustics Gaia feet (££). They "work" by decoupling the speaker from the floor. (Townshend seem to target the audiophile crew but IsoAcoustics make pro-audio stuff.)

I always thought that metal spikes under loudspeakers were de rigueur but I was curious. Squash balls are cheap so I decided to see what would happen with them.

I removed the spikes and replaced each of them with half a squash ball. The squash balls were ... err ... pretty well squashed but the loudspeakers still wobbled when touched - not excessively though.

Alas I am missing those "golden ears" so usually when I try something out (e.g. interconnect leads) I often (not not always) hear very little if any difference. But in this case I was surprised by how the stereo image and the instruments all seemed so much more sharply defined. This is inline with the discussions about the Townshend and IsoAcoustics products that I had read. (Whether my perceptions matched the reality is another matter.)

A bit of background:
My speakers are floor standing, quite heavy (approx 21kg each) and approx 1m tall. The room has a wooden suspended floor. I normally use spikes which rest on a granite "chopping board" (c/o Argos). Under each of the granite slabs there are 4 small blobs of BluTack to make sure they are "solid".

It might be that this type of decoupling would have a negative effect with less heavy speakers (i.e. which have less inertia) and/or with speakers spiked to solid floors.

All this sounds like the sort of dubious "magic" that you read about in audiophile forums, but I thought I would post it anyway.

John, it sounds as though you are slowly but surely becoming an audiophile...I myself am somewhat skeptical that placing little squishy things under heavy floorstanders would do much to alter the sound, but 1) I haven’t tried it, and 2) I can’t hear what you are hearing. If you think it sounds better, enjoy. I think that you had a proper dose of skepticism and that you are doubting your own ears. There are many others before you that believe such additions do help the sound, thus giving rise to companies that sell such accoutrement. So perhaps in some setups there is a real effect. It may just be that it is changing the angle of the drivers and thus altering the illusion that stereo creates. My recommendation would be to use such tweaks as you see fit, but spend as little as possible

[Mal]

"In all the years I've seen loudspeaker (and other) isolation products advertised, I have never seen data proving better audio quality. Magazine and online reviews contain only subjective assessments and user testimonials"

http://ethanwiner.com/speaker_isolation.htm

[jayne lee wilson]

"In all the years I've seen loudspeaker (and other) isolation products advertised, I have never seen data proving better audio quality. Magazine and online reviews contain only subjective assessments and user testimonials"

http://ethanwiner.com/speaker_isolation.htm

In which he claims.....

"Another fact is competent loudspeakers have sufficiently rigid cabinets that don't shake and vibrate very much. Yet another fact is wires and electronic components are mostly immune to vibration."

Did he never try, you know, resting his hand on top of any of them while the music is actually playing?
In any case he is ignorant of the rationale of the thin-walled speaker designs emanating from BBC Speaker Monitor research years ago (as mentioned on this thread yesterday....)

All these vast lists of measurements.....! To prove.....what, exactly? That speaker height/position is crucial to their sound? Well, who would have thought...

Just - Respect the laws of physics and how such energies may move around your (very influential, reflective/absorptive etc) room.... otherwise use your ears....(but have fun trying things out...)

Great quote from a recording engineer, IIRC Bob Ludwig:
"Not everything you hear can be measured; not everything you measure can be heard..."

[gradus]

Quite apart from speaker isolation, the RA site has some interesting articles about listening rooms and quite a lot of what seems like common sense too, but does anyone here have any experience of 'cleaning up' a mains supply to improve sound.

[Lordgeous]

RA major on lightweight wooden supports, to drain vibrational energy out of equipment resting upon it. I use their Oak Cone feet extensively, for 20 or 30 quid per 3 or 4 depending on size....their Torlyte platforms (lightweight but very strong wooden honeycombs) work on a similar principle...
(RA are very down on rubber feet!)

The decision to make is whether to try to contain vibration through mass, or let it out quickly to drain into the most massive parts of the room (usually the floor)..
With the designs themselves, e.g. ATC Speakers go for mass (try picking one up), Harbeth for thin-walled, screwed rather than glued together, rapid release of vibration....(this design principle followed BBC Monitor research years ago, vide LS 3/5A etc)... so for a Harbeth (e.g. my C7IIes) you'd go for spikes (points down...!) plus lighter-weight or part-filled stands to get the energy out of the cabinet quickly.

"Isolation" is possible but soft feet aren't very good at it....they may act as a partial barrier to floor-borne vibration, but airborne energy (from speakers, transports etc) can stay in the component. "Floating" equipment can be better, usually with opposing magnets attached to, say, perspex platforms....(perspex has a very low resonant frequency similar to some types of wood...)...but there's still the airborne vibe problem - wooden feet may help here...
(Stereophile once used an accelerometer to measure the effectiveness of some of these designs, they did pretty well...)

It is as ever down to choices.... consistency is best from a scientific viewpoint but you may still wish to tune the system by ear and mix the various possible approaches....

But very broadly speaking: the lighter the source component/loudspeaker: the more you may want to couple - to drain.
The heavier: isolation - mass - rigidity - might work better.... (it can be self-defeating for very obvious reasons...!)
But let your ears be the guide, as ever...(& try to work out how vibrational energy travels around your own room...)

Jayne, who ARE you with your amazing knowledge of music AND now acoustics! Please PM if you'd rather.

The first loudspeaker (pre stereo) my dad built for me was a sand filled corner unit. He even made the ribbon tweeter that stood on the top [exponential brass horn, huge ex-radar magnet, ribbon foil (KitKat bar wrapper!) and crossover with hand wound transformer. Many hours spent winding it!

I'm an ATC man (active SCM50s in the lounge, SCM10s for the TV and active SCM25s in my studio, stood on ceramic "spikes". My engineer swears they make a noticeable difference but I think my ears are too old now to appreciate such subleties.

[Mal]

In which he claims.....

"Another fact is competent loudspeakers have sufficiently rigid cabinets that don't shake and vibrate very much. Yet another fact is wires and electronic components are mostly immune to vibration."

Did he never try, you know, resting his hand on top of any of them while the music is actually playing?

He went a lot further then that! He measured the vibrations.

In any case he is ignorant of the rationale of the thin-walled speaker designs emanating from BBC Speaker Monitor research years ago...

He's an American audio expert so maybe he hasn't looked at what the BBC is up to in particular. But given his impressive website I wouldn't be surprise if he's looked at "thin walled speaker design". But I'll leave you, or the OP, to dig into his website if they want to look into this in detail.