isoacoustics isolators

[Patu]

So not even using the more effective ways of isolating the speaker (like GAIA or Townshend) and still he can measure the differences. Btw. You can measure the speaker cabinet vibrations even by iPhone with certain applications. Isolation mostly eliminates these vibrations.

Then again, comparing the speaker isolated vs coupled reveals that the difference in what we hear and feel is very clear and that’s really all that matters in this hobby.

 

[Purité Audio]

No ,not really at least not in this particular experiment, this is the left speaker ( right below) amplitude measurements using REW, ie what we actually hear.


Keith

 

[Sue Pertwee-Tyr]

Is that a test tone, Keith - pink noise or something?

 

[Purité Audio]

Quote,
‘An AES/EBU signal was sent to the loudspeaker. The stimulus signals used were determined and retained to be -22.70 dBFS RMS. Periodic pink noise at that level, band limited to 500-2 kHz, produced 80 dB SPL (C-weighted, slow).’

Keith

 

[Patu]

No ,not really at least not in this particular experiment, this is the left speaker ( right below) amplitude measurements using REW, ie what we actually hear.


Keith

I’m not sure if I’m following you. IsoAcoustics clearly states on their website that GAIA doesn’t affect frequency response and it shouldn’t affect frequency response. Its function is to kill vibrations travelling to your walls, floor and ceiling and at the same time those same vibrations can’t travel back to the speakers or our ears. Obviously frequency response doesn’t tell everything. We feel the music also, especially low end sounds. Resonations and vibrations also can affect the overall sound. Good example is when windows or glasses/plates in cupboard start to audibly resonate when you play music loud enough. This is completely eliminated with isolation.

 

[Purité Audio]

If the sound of the loudspeakers has changed then this will be reflected in the frequency response, the premise of these isolation products is that they remove/reduce the audible resonance caused by the structural transmission of vibration to the floor/walls/room.
I am not completely dismissing them, I have some properly designed isolation stands designed by Denial Mesanovic for his RTM10 monitors here which I must test, if you play loud bass heavy music in a room with a floor that resonates freely they may make a difference.
Keith

 

[Patu]

If the sound of the loudspeakers has changed then this will be reflected in the frequency response, the premise of these isolation products is that they remove/reduce the audible resonance caused by the structural transmission of vibration to the floor/walls/room.
I am not completely dismissing them, I have some properly designed isolation stands designed by Denial Mesanovic for his RTM10 monitors here which I must test, if you play loud bass heavy music in a room with a floor that resonates freely they may make a difference.
Keith

We can agree that frequency response stays intact with isolation. Isolation is about rest of the listening space resonating/vibrating/playing along with the speakers and also speakers being affected by these same resonations/vibrations. These sounds combined with the music coming from the loudspeakers is the end result which we experience and hear with our ears. I already got worried that you completely deny the difference isolation can make.

I've also experimented with isolation platforms under rest of my gear and I must say that I can't hear clear differences there.

EDIT:

Here's how IsoAcoustics explains it: https://isoacoustics.com/isoacoustics-speaker-isolation-technology/#_test_for_colorization

Here's how Townshend explains it:

These can be dismissed as marketing talks but some might be interested. Makes sense to me.

 

[Sue Pertwee-Tyr]

If the sound of the loudspeakers has changed then this will be reflected in the frequency response, the premise of these isolation products is that they remove/reduce the audible resonance caused by the structural transmission of vibration to the floor/walls/room.

My experience is that isolation under speakers improves things in the time domain, not in frequency response. Bass is tighter, more agile and more tuneful, and the musicians just sound like better players, having a better time. I put this down to a likely reduction in re-radiated sound, time-smeared, that my brain interprets as a vagueness in the music. I'm not sure a FR plot of a static (pink noise) signal will tell you much in terms of what's going on there.

 

[Purité Audio]

We can agree that frequency response stays intact with isolation. Isolation is about rest of the listening space resonating/vibrating/playing along with the speakers and also speakers being affected by these same resonations/vibrations. These sounds combined with the music coming from the loudspeakers is the end result which we experience and hear with our ears. I already got worried that you completely deny the difference isolation can make.

I've also experimented with isolation platforms under rest of my gear and I must say that I can't hear clear differences there.

EDIT:

Here's how IsoAcoustics explains it: https://isoacoustics.com/isoacoustics-speaker-isolation-technology/#_test_for_colorization

Here's how Townshend explains it:

These can be dismissed as marketing talks but some might be interested. Makes sense to me.

If any part of the room is resonating audibly that will be picked up by the microphone and added to the FR, remember the speaker is vibrating all the time, it is the loudspeaker designers job to ensure the enclosure does not store energy which could lead to audible resonance.
@ Sue, ‘boomy, bloated, one note bass’ is usually the result of room mode derived bass peaks which are clearly evident in the Fr, Katz also measures the RT times of his room in that paper, there is little appreciable difference.
Keith

 

[Sue Pertwee-Tyr]

If any part of the room is resonating audibly that will be picked up by the microphone and added to the FR, remember the speaker is vibrating all the time, it is the loudspeaker designers job to ensure the enclosure does not store energy which could lead to audible resonance.
@ Sue, ‘boomy, bloated, one note bass’ is usually the result of room mode derived bass peaks which are clearly evident in the Fr, Katz also measures the RT times of his room in that paper, there is little appreciable difference.
Keith

Perhaps, Keith, but I have successfully tamed boomy bass with isolation under my speakers, without changing the speaker positioning. Doesn’t that imply it’s not a room mode?

 

[Purité Audio]

If you have some before and after measurements I would be interested to see them.
Keith

 

[Sue Pertwee-Tyr]

You know full well I don’t Keith. Shall we take it as read that your position will be ‘no measurements, didn’t happen’ and just move on?

 

[John Phillips]

We can agree that frequency response stays intact with isolation. ...

I'm not so sure. I assume in the two cases, isolated and not isolated, the audio energy created by the loudspeaker is the same (is it?). It has to go somewhere. So it's tempting to assume frequency response (of the combined floor and speaker vs speaker alone) will say the same.

But in the non-isolated case where some of the energy is transferred to the floor, some may be dissipated as heat where the floor does not resonate and some may stay in the audio domain where the floor does. So I suspect the isolated loudspeaker response changes (maybe +0.8 dB if formerly it lost 1/10 of its energy to the floor in the non-isolated case). Therefore ISTM the combined response changes due to the floor being resonant at some frequencies and dissipative (non-resonant) at others.

Here's how IsoAcoustics explains it: https://isoacoustics.com/isoacoustics-speaker-isolation-technology/#_test_for_colorization

Here's how Townshend explains it:

These can be dismissed as marketing talks but some might be interested. Makes sense to me.

Having had successful professional experience of isolating sensitive optical lithography kit from upper-floor vibration I can see the possibility that isolation may be an effective tweak.

I haven't looked at the IsoAcoustics material but I have looked at the Townshend. I buy the idea of stopping the floor from becoming an uncontrolled audible extension to the loudspeaker cabinet (as per the BBC research) but I don't yet see a reason to buy the rest. No-one stomps close to my 'speakers on my concrete floor when I am listening, so it's not a case I think matters to me. And it's actually not clear to me that changes around the 1 dB level matter, even if audible. However I'm open to re-considering that position.

 

[John]

I'm not so sure. I assume in the two cases, isolated and not isolated, the audio energy created by the loudspeaker is the same (is it?). It has to go somewhere. So it's tempting to assume frequency response (of the combined floor and speaker vs speaker alone) will say the same.

But in the non-isolated case where some of the energy is transferred to the floor, some may be dissipated as heat where the floor does not resonate and some may stay in the audio domain where the floor does. So I suspect the isolated loudspeaker response changes (maybe +0.8 dB if formerly it lost 1/10 of its energy to the floor in the non-isolated case). Therefore ISTM the combined response changes due to the floor being resonant at some frequencies and dissipative (non-resonant) at others. Having had successful professional experience of isolating sensitive optical lithography kit from upper-floor vibration I can see the possibility that isolation may be an effective tweak.

Giving the audio energy from the loudspeaker somewhere to go is something that makes sense to me.
Here’s a bit from Symposium Acoustics website that explains:

Is a Symposium Platform an isolation platform?
Our platforms achieve a degree of isolation in the component by absorbing energy from two sources at once: from the component and from the support surface. Our platforms GROUND your component and give vibration that would otherwise be trapped inside of it a place to go, be dissipated as heat, and NOT be reflected back into your component (in either its original form, or a different, supposedly more benign one). You can think of our platforms as a kind of "sponge" for mechanical energy in the upper 8 out of 10 audible octaves- that is, from about the midbass (50-80 Hz or so) on up. These 8 octaves represent the lion's share of musical information, and by far contain most of what is needed to recreate a sense of "realism" and faithfulness to the original performance. But the word "isolation" is overused in this field of audio, because strict "isolation" is not the answer to the larger problem which we need to address, which is vibration control. Mechanical vibration affects the sound produced by your components because it works on the sensitive audio circuitry INSIDE your component, and merely cutting off one of the sources of vibration- the entry point at the feet of the component- without considering other sources, may not solve the problem completely or even adequately. It's important to drain energy from within the component as well as keep other external energy out of it. We therefore feel it is important that "isolation" remain a secondary and not a primary goal in the design of our products, and its role must be kept in proper perspective as only one of a number of disciplines necessary for better sound.

 

[Patu]

If any part of the room is resonating audibly that will be picked up by the microphone and added to the FR, remember the speaker is vibrating all the time, it is the loudspeaker designers job to ensure the enclosure does not store energy which could lead to audible resonance.
@ Sue, ‘boomy, bloated, one note bass’ is usually the result of room mode derived bass peaks which are clearly evident in the Fr, Katz also measures the RT times of his room in that paper, there is little appreciable difference.
Keith

I'm a strong believer of the idea that microphone can't replicate human hearing and all our senses. Frequency response won't tell everything about how something sounds, especially with speakers. With headphones, it might get close since acoustics and stuff like isolation won't matter. Part of what we hear surely is placebo but I don't care since that's how our senses work. In real world situation, we will always be aware of what we listen to and our brains will always do tricks to us. Only thing that matters is what I hear when I press play button and sit in the sweet spot. That's how I evaluate my gear.

 

[h.g.]

I’m not sure if I’m following you. IsoAcoustics clearly states on their website that GAIA doesn’t affect frequency response and it shouldn’t affect frequency response. Its function is to kill vibrations travelling to your walls, floor and ceiling and at the same time those same vibrations can’t travel back to the speakers or our ears. Obviously frequency response doesn’t tell everything. We feel the music also, especially low end sounds. Resonations and vibrations also can affect the overall sound. Good example is when windows or glasses/plates in cupboard start to audibly resonate when you play music loud enough. This is completely eliminated with isolation.

If a microphone placed at the listening position registers no difference in level or distortion with and without isolators then we can be confident the isolators are having no audible effect. The ear/brain is not particularly sensitive to level or distortion at low frequencies.

The plot posted above by Keith shows a change but because of the silly level of smoothing it is next to useless for seeing what is going on. If a competent measurement was presented showing the shape of the resonances we should be better able to distinguish room resonances and the structure-borne sound radiated from the floor, walls and ceiling. Effective isolation will reduce the latter but if solid floors/boundaries are present there may be little to reduce.

Transferring the sound in the air to the floor, walls, ceiling and windows is one of the main ways the sound radiated by the speakers is absorbed. Unlike the air there is normally significant friction/dissipation involved in moving them. This is a good thing not a bad thing if you want the sound of a note to be absorbed/decay fast enough to hear the following one.

 

[JTC]

I have to laugh at a lot of this, since the differences that these Gaias make is way bigger than I've experienced with any cable, and is quite a bit bigger than I've heard between any DAC. It's on the level of a cartridge change or something like that. I'd be surprised if it weren't easily measurable in the time domain by someone with enough kit and know-how, but in terms of static frequency measurements, it is meant to be fairly transparent. I personally have no idea how one would measure it reliably, but the difference is quite obvious. Whether it is to one's preference would be up to the individual, but my Gaias are definitely keepers.

 

[Cootie]

I’m with JTC on this one. Was really surprised by the extent of the improvement. Was expecting iterative but it turned out to be akin to a material component change.

 

[h.g.]

I'd be surprised if it weren't easily measurable in the time domain by someone with enough kit and know-how, but in terms of static frequency measurements, it is meant to be fairly transparent. I personally have no idea how one would measure it reliably, but the difference is quite obvious.

To repeat. If you can hear something at low frequency (in the identify from listening alone sense) then it will be easy to see in a measurement with a microphone at the listening position. There is an example posted above albeit with silly levels of smoothing removing much of the information that should be present.

Expressing a transfer function as a frequency response or a time response makes no difference. It is the same transfer function with one simply being the forward or reverse Fourier transform of the other. Anybody that claims that something is present in one and not the other is talking nonsense.

 

[yuckyamson]

The problem is that most of you people evaulate your system by listening to it. It's not objective Data.

I like to sit at home at night and after the kids are all off to bed, put on the robe, slippers, get a nice cup of Brandy, and measure the system repeatedly. Gated response. Frequency sweeps. Resonances. Barometric pressure changes. Off axis horizontally, vertically, diagonally. Then I stare at the graphs for a long, long time, and whisper sweet-nothings to them.

They tell me all I need to know. The measurements are my friends.

Listening to music is really a waste of time when you've worked so hard to get things "just right".