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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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michaelgreenaudio's avatar
michaelgreenaudio OP
1,019 posts
 

Here's a little bit of the more (you can do all these tests yourselves).

Do your echo tests.

Did you know that a first reflection test only works if you are outside in a flat open area with one single wall set up? The size of the wall and frequency played at the wall will show you which frequencies actual reflect and reflect intact. As soon as a second wall is put up (attached to the first wall) the reflection is altered. Add a third wall and you will have the development of pressure zones as opposed to reflections. By the time you have 6 walls the frequencies that will reflect in the room are. Mid to high frequencies in an echoslap and selective high frequencies in a wall reflection pattern.

Think about how far you can go, when you get out from underneath these audiophile prescribed myths. Keep in mind that the folks making these myths are folks who themselves are only theorizing. If they haven't gone and done they are doing the same thing that the "talkers" here are. I remember when Harry took his flashlight and came up with the first reflection thing. Cute, but it wasn't real. There's a big difference between drawing drawings and talking theory vs actually doing.

mg

bdp24's avatar
bdp24
9,414 posts
 
MG, I (bdp24, not dbp24; bdp for black diamond pearl---my favorite vintage drum shell finish, and 24 for the diameter of my bass drums in inches) intentionally didn’t include your acoustical products, fine as they are (I have your Room Tunes, Corner Tunes, and Echo Tunes), in my list of those to use with planars because I was speaking specifically in terms of diffusion of their rear wave. You don’t offer QRD or Skyline type diffusers, do you?
michaelgreenaudio's avatar
michaelgreenaudio OP
1,019 posts
 

Hi bdp24, sorry! You’ve probably noticed by my writing I have a mild form of dyslexia. I use to enjoy having a ghost writer, then when I started my own forum and he passed away I was like, sorry folks! My writing skills make me laugh when I read back through but it makes for good humor for my friends to have something to tease me about.

Also, I do enjoy reading your posts using your set as a reference point. Terrible player that I am I’ve had a few fairly nice setups and am like a kid being around drummers, their kits and talent.

Your also correct that I’m not so much into diffusers. I’m more of a direction and zoning guy. Even though some folks call my SoundShutters a diffusion type product, it’s more of a wall zoning device. The Areoplanes are another zoning tool that some put in the diffusion camp, but they’re really about organizing the zones and not diffusing them.

Have you ever seen one of my SS walls?

I do work a lot with back waves and even build special SAM walls made to go behind panels.

mg

geoffkait's avatar
geoffkait
23,365 posts
 
It’s a fluid situation in the room. The whole dynamics of speaker locations, listener position, the size and shape of the room and type and number of room treatments, among other variables, combine to determine the sound quality, all other things being equal. But as I pointed out in my last post, all this *uncertainty* changes when you employ the speaker set-up track on the XLO Test CD or similar Test CD. Using your own ears - move a little/listen a little - to try and find optimum speaker locations is bound to fail. You might find locations that you deem better than when you started but they won’t be the very best locations. There are a million possibilities. People get it into their heads that speakers should be far apart for a wider soundstage and toed in toward the listener. You will discover when using the Test CD that is actually not the case at all. Generally, most speakers should be closer together rather than far apart.

In any case, for those who experiment with room treatment and other tweaks like vibration isolation, etc., you need to re-visit the speaker set up track *every time* to add or change room treatments or tweaks. Otherwise, things can easily get out of control. Complexity is not your friend. In fact, the best course of action - remove all room treatments from the room, and using the out-of-phase track as a guide, slowly introduce the room treatments back into the system, moving the speakers as required to get the best results from the out-of-phase track. Then, placement of diffusers, absorbers, Helmholtz resonators, tiny bowl resonators, crystals, what have you, is a snap.

It also helps to have a SPL lever meter and test frequency track on hand to be able to map out the 3 dimensional space of the room to get a handle on where room treatments should be placed initially. For example, Tube Traps are sometimes best when placed a foot or two *away* from the room corner. It depends on where the standing wave sets up in a given room. There’s also the empty box trick for locating standing waves and similar sound pressure peaks in the room that can be employed.
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