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Talk but not walk?

Hi Guys

This isn't meant to start a fight, but it is important to on lookers. As a qualifier, I have my own audio forum where we report on audio issues as we empirically test them. It helps us short cut on theories and developing methods of listening. We have a wide range of systems and they are all over the world adding their experiences to the mix. Some are engineers, some are artist and others are audiophiles both new and old. One question I am almost always asked while I am visiting other forums, from some of my members and also members of the forum I am visiting is, why do so many HEA hobbyist talk theory without any, or very limited, empirical testing or experience?

I have been around empirical testing labs since I was a kid, and one thing that is certain is, you can always tell if someone is talking without walking. Right now on this forum there are easily 20 threads going on where folks are talking theory and there is absolutely no doubt to any of us who have actually done the testing needed, that the guy talking has never done the actual empirical testing themselves. I've seen this happen with HEA reviewers and designers and a ton of hobbyist. My question is this, why?

You would think that this hobby would be about listening and experience, so why are there so many myths created and why, in this hobby in particular, do people claim they know something without ever experimenting or being part of a team of empirical science folks. It's not that hard to setup a real empirical testing ground, so why don't we see this happen?

I'm not asking for peoples credentials, and I'm not asking to be trolled, I'm simply asking why talk and not walk? In many ways HEA is on pause while the rest of audio innovation is moving forward. I'm also not asking you guys to defend HEA, we've all heard it been there done it. What I'm asking is a very simple question in a hobby that is suppose to be based on "doing", why fake it?

thanks, be polite

Michael Green

www.michaelgreenaudio.net


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theaudiotweak
2,774 posts
 
Fellows you should study up on shear waves and their various velocities and polarities thru and on all solid materials in your listening room including solids in motion. Compressive becomes shear...on impact..or on solids in motion.Tom
geoffkait's avatar
geoffkait
23,365 posts
 
But there is air flow in the listening room, you silly goose. 🦆 For heaven’s sake, don’t have a conniption. 😫 The air molecules are pushed by the high speed acoustic (mechanical) waves, just as waves in the ocean push the water. So, there is laminar flow in the room, and in many directions, obviously. There would not be resonance without mass and there would not be mas without air molecules.

Some examples where baffles are used to organize or maintain laminar flow for audio applications include air baffles for air tubing for my air bearing everything Maplenoll turntable, 500 feet of air tubing, between the air compressor and the air bearing platter and air bearing tonearm AND a small baffle in the air spring connecting air fitting between the auxiliary air canister and the air spring per se, maintaining a smoother flow of air during operation, the air flow velocity in this case must certainly be quite low, no?
shadorne's avatar
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shadorne
7,467 posts
 
@geoffkait 

Wrong. You are conflating flow and vibration. The air particles in the room vibrate elastically at musical frequencies they do NOT “flow” around the room. There is no net air movement Flow = Zero, Capiche?
theaudiotweak
2,774 posts
 
Shear only travels in solids. Tom
geoffkait's avatar
geoffkait
23,365 posts
 
The reason it’s said that you want a large size woofer or large excursions of the diaphragm is because it pushes more air is uh, it pushes more air. The air moves. Hel-loo! As I said acoustic waves require air to propagate, analogous to waves on the ocean. The air molecules like the water molecules are moving, at least when the wave pushes through it. So when an acoustic wave hits a wall, air molecules are moving. It’s the frequencies of the of the (complex) wave that we hear and that produces resonance of objects in the room, not of air molecules. A standing wave has a frequency, although the air molecules at that location move along with the wave. Reflected waves have frequencies, the air molecules resonate at whatever frequency or frequencies the wave is moving. In a sense you cannot separate the acoustic waves from the air, there would be no sound without air. In space no one can hear you scream.

Pop quiz - do sound waves have mass?
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