IsoAcoustics Isolation Feet - Does it really make positive effect or fancy accessories

[Mort]

There is a special place in heaven I guess for those that persevere spikes and discs. I am a mere mortal and can not.

 

[MattHooper]

highly regarded speaker designer PAUL BARTON of PSB talks in this video interview about the nature of coupling and decoupling speakers from vibrating wood floors. Starts at about :50 minutes:

He points out that vibrations from a loudspeaker sitting on a wood floor (such as the one he describes) is going to cause sound vibrations to move through the floor to your seat where you will feel it. He says that since sound travels faster through a solid than through the air that is going to arrive before the signal coming through the air.
And so perceptionally we’re going to combine the felt vibrations with the heard vibrations.
And so for instance, a kick drum may give the impression of having more punch.

He leaves it open whether the effect is preferable - that’s up to the listener to decide whether they want to coup the speaker to the floor or decouple - but he says it’s there.

That makes sense of my own experience, decoupling my speakers using springs.
Without the springs under the speakers I could feel the floor vibrating around the base of the speakers and I could also feel the vibrations with my legs up on my ottoman and sitting on my sofa. But with the springs, the coupling the speakers the floor was completely dead of vibrations around the speaker, and I could no longer feel the vibrations through my legs either.
Plus, I could also measure the decoupling from the floor difference using a vibrometer app.

Perceptually I found that the decoupled speakers tightened up the bass and did some nice things but also sounded less palpable and punchy and solid, and took on a bit more of an electrostatic type character in my room.

I ultimately decided that I preferred the sense of solidity and punch with the speakers couple to the floor. However, I still liked some of the things I got from the decoupling. And therefore I started to experiment with different combinations of materials, including the isoacoustics Gaia, to look for a sort of partial coupling, but not full decoupling.

I also raised my speakers up higher because I liked the higher soundstage as well, but in some cases, it could cause the sound to get a little bit more bright and lose some bass impact. But I found the right combination of materials, really just by trial and error, that seemed to couple the speakers enough so that I could have them up higher and the total balance got just to where I wanted it and maintained base that was still rich and punchy but also tighter than when the speakers were sitting lower directly couple to the floor.

Work for me anyways, and I had lots of fun experimenting.

 

[kyuu]

highly regarded speaker designer PAUL BARTON of PSB talks in this video interview about the nature of coupling and decoupling speakers from vibrating wood floors. Starts at about :50 minutes:

He points out that vibrations from a loudspeaker sitting on a wood floor (such as the one he describes) is going to cause sound vibrations to move through the floor to your seat where you will feel it.

This is where my skepticism immediately starts kicking in. He may be a respected speaker designer, but has he actually tested this? The notion that vibration from the speaker's enclosure is not only strong enough on its own to travel through the flooring to your seat in a noticeable way, but to do so via the speaker's feet seems unlikely to me. It seems way more likely that you're going to get way more coupling to the floor through the air, since that's where the vast majority of the speaker's energy is going.

 

[MattHooper]

This is where my skepticism immediately starts kicking in. He may be a respected speaker designer, but has he actually tested this? The notion that vibration from the speaker's enclosure is not only strong enough on its own to travel through the flooring to your seat in a noticeable way, but to do so via the speaker's feet seems unlikely to me. It seems way more likely that you're going to get way more coupling to the floor through the air, since that's where the vast majority of the speaker's energy is going.

Fair enough but as I mentioned in my own experience, the vibration of the floor around my speakers when playing bass or loud music with very easy to feel beneath my feet, and also in my legs on my Ottoman, which disappeared when I decoupled.
So my mentioning this is of course just an anecdote for you, but it’s more compelling for me because I experienced it.

 

[OldHvyMec]

Evidence show me the evidence, if the footers audibly changed the sound then that will be measureable.

If that is the only thing you're looking for. All valve-based gear shows a marked improvement in tube longevity.

It's not just what you hear, it's what you DON'T hear rattling in the rest of the house, windows, and in my case, the ripples in the neighbor's swimming pool.

Think about driving in a car on a bumpy road, now think about being in a wagon attached to that car that has no suspension. I hope I've peaked your curiosity.

HOW Would sitting on an old wooden crate change the listening experience? Same height, the only difference is being comfortable. There are many measurements in music, and being comfortable is one of them that doesn't require a microphone. A stethoscope was used all the time in speaker cabinet making, along with checking for air leaks. NOT a microphone.

People are using a microphone to measure ONE thing when there are several things in play. You measure one type of vibration with a microphone; you use the appropriate accelerometer and attach the different sensors in different areas. You attach the sensors where cracks are developing, NOT a microphone, which checks for sound pressure differences.

Drop a 4cf box with 15A/18PR drivers on a wooden floor/stem wall. Spike it. (use spikes) Now LISTEN!
Now take the same box and use air ride, pods, springs, cable spring suspension or any combination and tell me what you like vs what you measured.

That is one huge passive driver you created by coupling to that drum head called the floor. Do you really need to measure that, or would that result be enough to rethink spiking any cabinet that can radiate a vibration into gear? EX: Valve equipment, turntables, CDs, RtR, or Cassettes. Not to mention the adjoining rooms, down/upstairs, neighbors, etc.

Using a microphone to measure vibration shows that the individual didn't know a thing about what they were trying to measure in the first place.

The notion that vibration from the speaker's enclosure is not only strong enough on its own to travel through the flooring to your seat in a noticeable way, but to do so via the speaker's feet seems unlikely to me. It seems way more likely that you're going to get way more coupling to the floor through the air, since that's where the vast majority of the speaker's energy is going.

Sad to say, you need to do a little more research before making a statement like this. One of the most outdated areas of engineering is in the music reproduction industry. Vibration control has been used in every major industry involving moving parts. What on earth makes anyone think that equipment, along with speaker cabinets, is somehow immune to studies that have been going on since they first added springs to chariots/horse and buggy, and then on to motor-driven vehicles?

Once again, using a microphone is not the correct tool to use when measuring a lot of the things that seem to be neglected in the HiFi world. It's like the question of break-in. It's strange it's in every owner's manual or every car/equipment, or machinery ever made, BUT somehow it doesn't exist in the music gear industry. ALL light, medium and heavy equipment requires a 100-hour service before being returned to a normal service life cycle. Even my vacuum cleaner instructions said not run the machine for protracted periods of time for the first 10-25 hours.

Regards

 

[kyuu]

Sad to say, you need to do a little more research before making a statement like this. One of the most outdated areas of engineering is in the music reproduction industry. Vibration control has been used in every major industry involving moving parts. What on earth makes anyone think that equipment, along with speaker cabinets, is somehow immune to studies that have been going on since they first added springs to chariots/horse and buggy, and then on to motor-driven vehicles?

Please show me the research that shows that a significant amount of energy couples from a speaker cabinet to the floor through some little feet, and which requires elaborate "decouplers" to avoid. Also I'd like to see how this compares to the amount of energy that couples from the speaker to the floor via the air. Until then, sad to say you have no more of a leg to stand on than I do.

 

[MattHooper]

I was reminded looking at my old thread on trying stuff under my speaker that at one point a certain combination of materials was causing overblown bass to the point that for the first time I was having the problem with an audibly rattling grill on one of my speakers. But when I used certain other materials the bass was more controlled and the rattling stopped. It was very repeatable.

 

[Purité Audio]

And what actual physical medium could possibly cause that Matt?
Why do you so desperately want to believe in BS products?
Keith

 

[MattHooper]

And what actual physical medium could possibly cause that Matt?

The speaker grill was literally rattling audibly to the point I had to take it off the speaker when the speaker was placed on a certain substrate, but this was not an issue when he was sitting on some other materials. And it was repeatable.

So you tell me.

Perhaps you might want to default to the idea that I’m lying, or that I completely imagined the distracting rattling grill, as you are pretty fixated on dismissing out of hand anything I write about my experience on this.

Why do you so desperately want to believe in BS products?

You’ve really got me pegged there

I think I’m getting to the point where I agree with what somebody else once said here
“ the best Keith is an ignored Keith…”

 

[kyuu]

I was reminded looking at my old thread on trying stuff under my speaker that at one point a certain combination of materials was causing overblown bass to the point that for the first time I was having the problem with an audibly rattling grill on one of my speakers. But when I used certain other materials the bass was more controlled and the rattling stopped. It was very repeatable.

I can't recall if I saw that old thread. Was it determined if the materials you were using were resonating themselves?

 

[Purité Audio]

Rattling grills… quality product!
Keith

 

[MattHooper]

Rattling grills… quality product!
Keith

I set my countdown timer for that most predictable of all responses.

Oh Keith…

 

[Purité Audio]

‘How I fixed my rattling grills and it only cost me £1000!’
Any subjective site would lap that up.
Keith

 

[MattHooper]

I can't recall if I saw that old thread. Was it determined if the materials you were using were resonating themselves?

I’m not sure exactly what you want to know in this question.

But I tried various footers, spikes, granite, MDF, sorbothane, wood lifts, springs, hockey pucks, isoacoustics pucks and Gaia footers, etc. In various combinations as well to see their effects.

So certainly any number of those products where resonating beneath the speakers (for instance the wood, or spikes coupling the residences to the floor) where other soft materials were providing damping, and springs were providing mechanical decoupling.

Does that answer your question?

 

[MattHooper]

‘How I fixed my rattling grills and it only cost me £1000!’
Any subjective site would lap that up.
Keith

You misunderstand. I had no problem whatsoever with rattling grills with the speakers set up as they normally suggest, just sitting on their outriggers. Nor in the vast majority of set ups in which I tried various materials under the speakers. Only one or two set ups caused one of the speaker grills to rattle, with obviously more overblown bass than usual from the speakers.

Currently, I have my speakers on the granite base that I designed - no rattling whatsoever. And again, there is no rattling of the grills with the normal use of the speakers, and I have never seen any other report of rattling grills on Joseph speakers.

 

[Mark617]

Ethan Winer conducted several tests to elucidate if there is a beneficial effect of isolation products for loudspeakers due to the mechanical vibrations when playing sound (music, etc.). Winer measured the performance of a Mackie HR624 powered loudspeaker placed on a table that had strong resonances at 298 and 475 Hz when used as stands for a pair of speakers with and without commercial (4) and DYI (2) acoustic isolation products. Measurements for frequency, decay times, and impulse responses were made with REW and and DPA 4090 precision microphone.

Mr. Winer detects and reports some small differences between the various isolation products and no isolation by less than 2 dB’s. He concludes that they differences are mostly due to slight differences (down to ⅛") between speaker and microphone placement although he sought to counter this variable as much as possible.

Check this: Speaker Isolation.

 

[kyuu]

Check this: Speaker Isolation.

Nice, seems to confirm my suspicions that there just isn't enough energy in the speaker cabinet (at least a decently built one) to worry about it coupling to the floor (or whatever surface it's sitting on). Any actual audible change seems to be due to movement of the speaker itself, whether just the height from the isolation product itself or inadvertently slightly changing the position while installing the product, which of course we know certainly can make a significant difference.

 

[jcarys]

This is where my skepticism immediately starts kicking in. He may be a respected speaker designer, but has he actually tested this? The notion that vibration from the speaker's enclosure is not only strong enough on its own to travel through the flooring to your seat in a noticeable way, but to do so via the speaker's feet seems unlikely to me. It seems way more likely that you're going to get way more coupling to the floor through the air, since that's where the vast majority of the speaker's energy is going.

Believe me, when you're talking about Paul Barton, I can guarantee that he has tested it. He was one of the first people to test all of his products in Canada's National Research Council anechoic chamber. If you don't believe his ears, that's fine, but I'm sure he arrives at his opinion after quite a bit of listening.

I think the other thing that is off base in this conversation is the concept that speakers are only going to be on a few small feet. Before I added rubber feet, my entire speaker's flat bottom was on hardwood floors, so 198 square inches. That is quite a bit of direct connection between the movement of the woofers, speaker cabinet, and floor.

I have auditioned the IsoAcoustics products. I thought the sound effect was pretty damn obvious to anyone with ears. You got less bass from resonance, which made the midrange stand out a bit more in contrast. The issue for me is that I don't think it's a $500 difference. If I wanted to effect that change, I would simply do it with equalization.

 

[Purité Audio]

The feet made the speakers produce more bass?

Check this: Speaker Isolation.

Precisely what we found when we measured just not enough structural transmission despite playing extremely loudly and as the company stated there is still airborne transmission to consider.
Keith

 

[MAB]

I can't recall if I saw that old thread. Was it determined if the materials you were using were resonating themselves?

No. Acoustic measurements weren't provided. Despite the fact the phenomena is eminently measurable and measurements were asked for many times. About halfway though the thread it was seen that the height, angle, and position of the speakers was being changed with the different materials. How that affected actual sound is a guess, but as we know speaker position in room has a large impact on sound. So run to run was not controlled, and sighted listening was the measurement method.

In that thread I did a moderately careful test of hollow speaker stands with and without sand. They rung like a bell when struck without sand, and were quite dead after filling with ~10 kilos of fancy sand. The sand was some boutique sand from my days in sales. I think it is just coated in parafin.

Springs Under My Speakers: What's Happening?

LOL, let's keep going, prove that you have a window. I want proof Purite Audio even made that post before it's worth answering. Could have been hacked. Or his wife posted while he wasn't looking.

www.audiosciencereview.com

I controlled for position extremely carefully. Differences are tiny, well below run to run variability. I also did systematic changes position and angle to test the sensitivity to placement. As expected, even small position changes lead to very measurable changes in sound. Millimeter changes were on the order of my observed changes. I was not able to be millimeter perfect in returning the speakers to the same position after I filled the stands with sand. So it was important to establish the baseline variation due to placement accuracy. And also to illustrate what happens when you even slightly move speakers.

It's pretty unreasonable to think that even a stand can resonate enough to radiate energy comparable to the speaker.

Nice, seems to confirm my suspicions that there just isn't enough energy in the speaker cabinet (at least a decently built one) to worry about it coupling to the floor (or whatever surface it's sitting on). Any actual audible change seems to be due to movement of the speaker itself, whether just the height from the isolation product itself or inadvertently slightly changing the position while installing the product, which of course we know certainly can make a significant difference.

Exactly. The problem is the radiated sound of the speaker is what couples to the floor. I've also measured different feet on hardwood floors of our old house.

I measured both sound:

Tower speakers on hardwood floors: spikes on discs/coins? Sorbothane/silicone pads? Springs?

From what I gather it seems to not matter much for a regular concrete floor, but what about tower speakers and subwoofer for a pier and beam type house ?

www.audiosciencereview.com

And distortion:

Tower speakers on hardwood floors: spikes on discs/coins? Sorbothane/silicone pads? Springs?

From what I gather it seems to not matter much for a regular concrete floor, but what about tower speakers and subwoofer for a pier and beam type house ?

www.audiosciencereview.com

This null result is no surprise. I spent a few years working with customers who had bouncy floors, skipping and howling turntables, and other room issues like buzzing ducts and windows. We had a beat up subwoofer and tone generator to sort out issues with customer's rooms. Mics and analysis gear were near unattainable even to commercial and high end installation companies back then. Unfortunately, if you have a bouncy floor that is what you have. You can change speaker position to change the modal bass patterns, decoupling can help a smidgen, but the majority of the motion of the floor is due to the floor coupled to the air in the room.

Edit: fixed a sentence.