Auva Footers

[stvnharr]

I was fully aware at the time of my initial post of what I was doing. I was posting a listening impression in a forum that is fully oriented to graphs and measurements, and I had no graphs or measurements. I expected a lot of push-back, disbelief, etc., or to be completely ignored. But, since the posting in the recent Iso-Acoustics thread was mostly polite, albeit there was a graph and measurement included, I went ahead and posted. I just wanted to put it out there, and I did that.

 

[MaxwellsEq]

I was posting a listening impression in a forum that is fully oriented to graphs and measurements, and I had no graphs or measurements

The forum has "Science" in the title. It's possible to go down a rabbit hole on this, but in general, someone has an idea and they they then define a repeatable (by other people) experiment to confirm or undermine that idea; or they make an observation and derive a model that consistently confirms their observation. The problem with your approach is - I can't repeat your experiment! It's all about you, and only about you. And this simply means it can't fit into anything scientific.

We know (e.g. from medical research) that the placebo effect is strong and reliably repeatable. There are also multiple, repeatable experiments since Daniel Kahneman and Amos Tversky that confirms we are irrational and are unable (no matter who we are and how hard we try) to overcome our inbuilt biases and heuristics. This means we can not simply trust what we observe, but must build repeatable (by other people) tests. As you state above, you knowingly didn't do that.

Fortunately many other people have worked on repeatable tests - so, for example, we know that moving a loudspeaker a few inches in a room in any of the three dimensions, significantly changes its interaction with the room; height is especially sensitive since most ceilings are untreated. Any experiment with isolators under a speaker needs to account for this. We also know that most speakers have a reference level (often the tweeter) and that sound frequency response and sound dispersion changes when your ear is a few degrees off this level. Any listening experiment needs to account for this (however, sitting an inch higher has the same room-interaction effect as moving the speakers does!).

Given these challenges, it's actually simpler to use a microphone to capture the changes than to derive a reliable, repeatable listening test! That's why you were given the guidance you received.

 

[stvnharr]

Thanks for your guidance.

 

[Greenman]

Do these footers make an audible difference? ….i don’t know…but I was always led to believe that speakers should have a good solid connection to the floor as this would allow them to more effectively transfer their energy into the air. Without a solid floor connection then the speaker is liable to move/vibrate which pollutes the sound being transferred to the air. Now whether any of that is audible I don’t know but it does seem to make sense.

Are speaker vibration transferred to the floor? Yes and easy to confirm, just put your hand on the floor while playing music and you can feel the vibrations. (If you are lucky enough to have stone/concrete floors then probably these will not be obvious, but on my wood floor they are very clear)
Are speaker vibrations transferred by air? Of course, but put your hand on the wall and the vibrations are much less than on the floor. For this reason I mounted my turntable on the wall and as far from the speakers as possible.

So…it wouldn’t be a surprise to me if some sort of complaint suspension did make an audible difference, by say maybe softening transients, doesn’t sound like a positive change, but in some systems who knows.

 

[Purité Audio]

Is enough vibration transferred to create an audible resonance?
Speakers ‘should’ be designed they do not store energy which could lead to audible resonance, footers are the equivalent of buying a tigers tail for your pushbike.
Sorbathane ( open cell rubber) inexpensive and effective
Keith

 

[stvnharr]

Well, regarding some things brought up in a posts #42 and 45........
I thought to be self-evident that my experience was just my experience. It was significant enough to me that I posted about it. It is not more than that.

I should also include some more information about my speaker. The speaker is a one off, so I have the only one. It is closed box design and full of acoustic stuffing. While it looks like a floorstanding speaker. It is only in looks. The original is a standmount design. When I did the remake, I built the stand into the speaker, making it look like a floorstander. Bottom half meter is stand and top 600mm is the speaker. The speaker was not designed in an anechoic chamber at any point in the design process.

I might add that my previous speaker was the Waveform Mach Solo speaker. This speaker was designed completely in the NRC lab in Toronto, over a period of up to a couple years. The speaker had ruler flat frequency response of +-1db. and no resonances. It had the best waterfall plot of any speaker I ever saw. John Otvos provided complete measurement data and graphs in his speaker information. I bought the speaker solely on John's provided information. There was no audition at all. There was a rightness to the sound that you could tell in the first five seconds of any play of music.

Thus, I have been at both ends of the speaker spectrum, as far as design and engineering. Make of that what you will, if anything.