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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


michaelgreenaudio
michaelgreenaudio's avatar
michaelgreenaudio OP
643 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
14,147 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.
elizabeth
6,726 posts
 
Going back to what MG wrote: "" 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.  ... There's a big difference between drawing drawings and talking theory vs actually doing. ""      
.                     
Which was the original start of this thread. When I wrote I did my speakers my way, not the theory of the 5m/10ms, seemed like the theory had to be defended by the person who mentioned it, rather than accept what worked for me,  it just is someone's made up theory and I find it to not be of much use. (sure it is true 10ms takes 10m however in practical use, it does not correlate to a 5m distance from the rear wall)  
That is the thing with notions. Once you have them IN YOUR HEAD, folks tend to defend them, like personal property. So I really liked this thread.. as it brings to the fore problems of dogma, and the stuff folks just carry around.. preventing them from looking at problems in a fresh way.
jtcf's avatar
jtcf
303 posts
 
I'm enjoying this thread.When others post about actual experience even when it's the opposite of what I believe to be true,I'm open to learning more about it.Instead of "Oh that will never work!" I'm in the camp of "Hmm,gotta investigate further".
michaelgreenaudio's avatar
michaelgreenaudio OP
643 posts
 

There was a mastering room I was doing some work on in Nashville. The engineer was remastering some SNL shows and had ordered in some new amps and speakers at the same time I was doing my thing in there. The guys from the speaker company and the mastering engineer were sold on the idea that for true staging there was a certain placement formula that needed to be used. Fine, wasn’t my gig so they did their thing and at the end of the day it sounded horrible. No one liked it, but they were determined to stay on course. A day or two later I asked if I could set things up for the heck of it, and after I got some dirty looks they said go ahead. 2 hours later it was like the SNL cast was walking through the room. Everyone was pretty freaked out and one guy super mad suggesting what I just did couldn’t happen :)

I’ve been through this same thing hundreds, probably thousands, of times in person. Same thing happened when I was a mic tech. The only formula that works is the one you create.

another Nashville example

I was tuning up a drum room and the drummer kept getting mad at me the way I was doing the miking on the kick drum. He got stuck in his head that kick drums don’t have a note but instead are raw pressure. (guess he never met "sugarfoot"). It was a long day and every time we went into the control room you could hear the kick was out of tune throwing off the bass line. Stubborn as he was we ended up retuning the room and kick and mics together. You know how I fixed it. A little thing called a pressure box.

A lot of folks in this hobby try to make full range speakers do what a room is telling them not to do. Right around 80hz and down panel speakers (all speakers) start to challenge the rooms walls density. One little move and the speakers will shift upward. You might get your staging just about right and then play another recording and there’s that range shift. People blame it on the recording or start looking for other components or start filling their rooms with traps, instead of realizing the walls in the room are having a conflict with the mechanics of the speakers. Somewhere in that room there is a pressure build up or the opposite keeping the bottom notes from fully forming. Major problem right? Nope, it’s actually an easy fix. You can get a professional Pressure Box made from me, but to take care of the basic problem you can make your own ported pressure box and move it around the room till it activates and restores the pressure in the room to balance.

At the end of the day, don’t get stuck on numbers. Learn how the control pressure. And always remember, your not hearing the speakers, but pressure. Once you start treating your room like a speaker things get a lot easier.


mg

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