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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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geoffkait's avatar
geoffkait
23,365 posts
 
Glad you asked. I was going to say before that I have been using many types of wood for like forever. For my first iso stand I used cherry, oak, maple, and Baltic birch for the strength member. For the next iso stand Promethane I used mostly maple but also Baltic birch for the plates. I also experimented with a range of hardwoods to gauge their effects on the sound, like the foot long planks against the wall. I think the next thing that happened after than was I discovered crystals. 😬 of course others have experimented with various woods, e.g., Shakti Halographs, Myrtle wood blocks, and I can’t recall the dude’s name who roamed CES back in the day demonstrating his contraption made of many different types of wood. There are also other Shun Mook devices that employ ebony other than Mpingo, but the idea is the same - highly resonant wood that exhibits directionality. Spatial Kit, Diamond Resonators, Shun Mook record weight. Sugar Cubes from Franck Tchang are also wood.

theaudiotweak
2,797 posts
 
All examples of resonance transfer of shear waves from one surface in contact with another material and shape. The resonance outcome of both materials and shapes are unpredictable I think. How their motion results in a different compressive sound is also unpredictable. Experience with materials and shapes maybe the best tool under the ear. Probably why the Mpingo discs work in some places for some and others not as much. Also a experienced listener and tweaker may find a better result in a shorter amount of time than the less experienced.Tom
geoffkait's avatar
geoffkait
23,365 posts
 
Sorry, Tom, wrong again. Resonators do not have to be touching anything. They could, it might be convenient, but it’s not necessary. They can be just hanging there in free space. Like the Shakti Hollographs. Or they can be located where there is mechanical vibration where they convert the mechanical energy to heat. You know, like the Dampers I used for twenty years to allow energy to exit the system. Your Polarity of Shear theory has run aground, as it were. But I enjoy watching you trying to guess how something works. Very entertaining.
glupson
7,842 posts
 
theaudiotweak,

"All examples of resonance transfer of shear waves from one surface in contact with another material and shape."
Could, for this purpose and in some theoretical ("talking") sense, a fluid be considered "surface"? I mean, does what you are proposing have to be two hard mediums or any of them could be fluid? It may seem off-topic, but it is not in the longer run.
theaudiotweak
2,797 posts
 
Geoff,

I know how they work.  Your brain only works in the compressive world same as you think the Shakti Hollographs only do. When a compressive wave passes across the solid surface of the varied forms of wood of the Hollographs that wave turns into a shear wave ( only in a solid) . That shear wave motion causes the solid to move slightly.. the  air around that shape to vibrate and the fact that there are 2 different species of wood of over basically 6 different sections and lengths you now have a change in the compressive wave 6 different times per single unit. Now that 6 times does not take into account the boundary areas where  the twisted pattern in the wood is held at each end..nor does it take into account where it appears there 2 different species of wood joined together at their intersections..All those areas now included  have a different shear velocity as do the 2 different species of wood as do the different sectioned lengths that  cause a change in air motion and that is what you hear when those waves come in contact with other solids like the wall surface and your eardrums..they too resonate and cause a change in air motion... So how many times are those shear waves in all those materials and shapes make for change in your compressive world?  Tom


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