How to get better sound? - Page 7

is AJ going to post his measurement file so we can see the measurements of his speaker from within that room without 1/6 smoothing?

what is he trying to hide? is the room's boundaries imposing frequency response anomalies??? hmm. www.sendspace.com, AJ - please upload so we can take a look! you're the one selling the product and making the claims.

Sure, right after we see localhosts first measurement of anything done by localhost. Lets starts with your wallmount JBL Studios. Higher rez FRs and of course your favorite ETC, ETC, ETC, ETCs that you type about endlessly.

By appearing at numerous public audio shows across the country over the years? Nothing.
What would a "localhost127" anonymous poster wish to hide? Hmmm....
Are the neighborhood kids allowed to visit you in the basement A/V cell...assuming one exists?

What specific claim might that be?

he can't stop deflecting! he has nothing further to show. 1/6 smoothing brochure measurements. can't back up his claims or product.

just post the file, AJ - www.sendspace.com

what are you hiding behind that 1/6 smoothing?

now ill wait while he hurries back to his "Toole paper" as he frantically tries to dig up out-of-context quotes like he continues to do.
all he can do is repeat what Toole states - he has little knowledge of acoustics to his own.

but hey, what else do you expect from a Flatlander stuck in the frequency-domain!

No ETCs? Have you ever actually done any measurement in your life? No? None, zero?? Hmmm...


I'm hiding my name behind localhost127 and I'm hiding pics of my wallmount JBLs in the padded cell. Too embarrassing for public viewing.


You mean the subwoofer salesman?...at least according to the anonymous localhost127 with the wallmount JBLs that sound identical to UREIs

what is causing those peaks and dips through this 1/6 smoothed frequency response? why doesn't it match your anechoic measurements?

post the actual measurement file - i'd love to post what it looks like with no smoothing for the forum to see. can your product not stand up to this test? what are you hiding behind that 1/6 smoothing?

comon, AJ - i know you are more able to stand up for your product than this. "Soundfield Audio Loudspeakers" or "Soundfield Audio Smoothed Loudspeakers"

Thanks for clearly showing that they do indeed extend to 30hz and below in a typical listening room, as claimed by the manufacturer! Bravo.
Now, what sort of in room extension do these have:

What about ETCs? How are those in your room with the wallmounts?
What perceptual relevance do they have?
How do you get them to sound perceptually indistinguishable from UREIs, Genelecs, Tannoys, etc, etc...depending on which recording you "accurately" recreate, while "listening critically" in you critical ward soft padded cell?
How do you confirm this accuracy?

Soundfield Audio 1/6 Smoooooooothed Loudspeakers.

when can we expect the new marketing brochures at 1/6smoothed FRs?

this is too fun - this is what happens when you come here to market and sell. your claims get picked apart and put down.
post the measurement file or continue with your childish tirade worthy of a speaker salesman.

AJ,
i'd love to see what your speakers can do in a Toole living room. mind sharing with us the measurement file of your speakers in such a room? im not interested in your padded-cell anechoic chamber measurements that are on your brochures.. im looking for real world / typical Toole living room performance data here on your product.

can you provide this, or no?
remember - YOU are the salesman, here - not me. the onus is on you to provide data on your products.

My claim of <30hz extension was clearly met, thanks for showing it!
Now, about your claim of the importance of measuring, the importance of ETCs, how your "critical listening" cell is "accurate" to recordings you weren't present for, how your little JBL wallmounts are perceptually indistinguishable from UREIs, ETC,ETC,ETC...?
Well, this is too fun - this is what happens when you come here to market and sell studio bubbleworld products...your claims get picked apart and put down.

why did you need to perform 1/6 smoothing on the FR to show < 30 hz extension?

what drove you to make that decision? surely there must be something in the data you are hiding; why do you need to smooth your graphs to make them look better than they actually are?

all of this - ALL of this could be settled by posting the measurement file from that room so we could see for ourselves

as the salesman here, are you willing to provide this data for your product? as a possible customer, i would need to see such data before making a decision. can you meet this request for a possible customer?

step 1: smooth the frequency responses to hide what's really going on
step 2: ???
step 3: profit!

A Toole living room? You mean yours?
Haha, of course not, you live in a cell...my bad.
If you are allowed out of your cell perhaps we'll make a road trip together?
I'll just look you up in the phone book under (Mr?) Local Host127. Strange name I must admit.
You won't insult him by calling him the sub salesman will you?

If you measured or knew anything about measurements, you'd understand.
But you don't.....

The lack of a 3rd (or 4th) sub in the hotel room. Only needed one at RMAF to get it withing +/-3 at every seat. Didn't bother at this one or CapFest, yet alas....perceptually no complaints, only compliments.
You ever get any from visitors to the cell? What are the perceptual comments by visitors to the JBL Studio wallmounts with all the padding? Can they hear your nice (imagined, not measured) ETCs?

the guy who presents 1/6 smoothed FR's is telling me that i dont know how to take measruements.

lol.

AJ, how much of a padded cell do i require before my frequency response with your speakers evens out to the point where it matches your brochures? would i need as much padded cell to construct an effectively anechoic chamber to get there?

www.sendspace.com - please link to your measurement file so i can analyze your product myself. thank you,

and why did you need to perform 1/6 smoothing on the FR to show < 30 hz extension? shouldn't an unsmoothed FR show < 30hz extension just as easily?
do you have any further copy-paste quotes from Toole that can help assist you here? you seem to be stuck and having difficulty producing data for your products.

Yes. And that fact is undeniable. That is why you have no measurements to show. None.


Repeat that slowly to yourself until it makes sense.


Not if you already have one. Or at least purport so.


No need, because the extension is what I'm showing.
Why do you need to hide from the shame of your name, room, speakers, lack of measurements, etc?


Mr. ETC, ETC, ETC, ETC want's another quote from his sub salesman? Ok, sure, I'll oblige:

Now about those JBL wallmounts of yours, being perceptually indistinguishable from UREIs, ETC,ETC,ETC... during "critical listening" in your cell????

keep digging!
you're almost there!

Here's my room...

The exact same measurement displayed in two different ways...

Ah, didn't realize you guys continued this party without me .

Your graph is right but your complaint, not . Let's cover each. The graph comes from Cox and D'Antonio's book on diffusers and acoustics. What it states is absolutely true. Due to high air velocity near the wells, if you stick a resistive material in front of it, you will create an absorber. Hence the reason some people sell combo diffusers/absorbers by following this research.

You did not provide attribution/context for the graph. Had you done that, folks could read this bit after it by the author: "Any cloth covering should be placed at least a well width away from the front face." While not that easy to see, our side walls are quite deep. The acoustic material is shallower than them. Further, there fabric is on tracks that stand out past the maple wood framing you see on the face of the wall. All in all, there are good number of inches of space between it and the diffusers. In addition, Keith spec'ed and we used material which has less resistance than the typical GOM fabric people use (sadly the graph above does not stipulate what material was used). All of this helps to reduce the effect. How much? Well, there is some data we can draw up in the form of measurements by RPG for their diffusers:



We see that as the material moves away from the very front of the diffuser, the absoption coefficient reduces. The top purple is what Cox and crew showed in their graph. The red is what happens when you put good bit of distance between the fabric and diffuser. Sadly RPG doesn't spec either what cloth they used.

Bottom line, don't go wrapping your diffuser as I see many times with fabric hugging the material. Also note that the diffuser even without the fabric has a non-unified absorption.

So yes, we have an undesirable effect here. And it is not the only one. That fabric so far away from the side wall acts as an absorber even when it is not in front of the diffusers. Heck, why stay with audio? Our front wall uses an acoustically transparent screen to hide the speakers and acoustic treatments. The woven pattern certainly is not the ideal material for video. Why did we do all of this then? Because good engineering is a matter of good compromises!

The goal for a reference class home theater is to have you be lost in it. To make you forget you are in a theater but in the movie scene itself. There is no way that illusion works if when the screen brightens, you see all that structure and acoustic material on the wall. That may warm the heart of whoever spent money on them, but it completely deters from that one important goal: "suspension of disbelief" as Keith calls it.

To be sure, I had to be taken there kicking and screaming . Two years ago you wouldn't catch me dead with an AT screen. Solid, 1.0 gain matt had to be it. But just spend one or two minutes in our theater and you forget where you are. You get drawn into the picture in a way that no front wall with speakers showing would ever do. When I am showing it to my friends and such, as soon as I stop talking, I see them mesmerized by the *total* experience* and I have to force them to look at me and listen. You think right in the middle of that they are hearing that increased absorption that you so worry about? I think not. You have to optimize for the entire experience and that might require compromise in a few details.

This brings us to another important point I have been making which is how easy it is to screw up these acoustic material. Which consumer who buys one of these diffusers would think twice about covering them? Heck, I have seen people do that and even write up their build threads that way.

So no, our theater design didn't come from taking a two day class or reading a book. The audio was designed by Keith Yates who is a master at the perceptual effects I am talking about there. I did the video but happy to continue to explain our design choices.

Can we see your listening room by the way?

Looks like you have 30hz extension and sh***ty speakers.
Have you tried buy-wiring them to improve the sound? Oh wait, never mind http://larchive2.avsforum.com/www.av...1395638&page=2

I actually have a room that doesn't like 100 Hz. Those speakers would measure much flatter if I took the reading outside on the front porch. Bring them into the room and things change.

Those measurements are actually from a new house I had just moved into last month. Am still getting things sorted. The measurements from my previous house looked different. Why do you think that would be? Could it be the room?

But funny how if I cut off my graph at 200 Hz and reduce the resolution and increase the dB range... they look like a flat line?

So where's your full range graphs at higher resolution...???

Oh! When did you buy a pair of AJ's speakers assembled from Parts Express pre-manufactured cabinets?

And BTW, 1/12 smoothing is good for nothing but marketing brochures where the limited data serves little but to obscure actual performance. Funny how few distribute actual complete profiles such as CLF or EASE DLL performance files.

"Due to high air velocity near the wells, if you stick a resistive material in front of it, you will create an absorber."

Not quite. And you miss the much larger topic had you bothered to actually read chapters 7 and 9 and become aware of the additional (then new and unreleased) research referred to but not specifically cited.

And as far as the absorptive characteristics of diffusors, its amazing that we refer to RPG marketing materials and not chapter 7 and 9 of Acoustic Absorbers and Diffusers where they specifically address "how to make efficient absorbers from Schroeder diffusers. Researchers started by looking into why the absorption from Schroeder diffusers could be large, and ended up inventing a new style of absorber."(p.230) "...Concerted scientific studies have been able to determine the source of the absorption, and even to show how to turn these diffusers into good absorbers. By changes in geometry and design, it is possible to change a Schroeder surface from a diffuser with low absorption to a highly absorbing surface. This is of great concern for diffuser installation, as it is very easy to accidentally make a highly absorbing surface through bad workmanship."(p.232).

But the real insight results when one realizes that there are multiple mechanism whereby porous membranes can be applied in a variety of manners are applied the turn the Schroeder diffusor into a high quality low Q absorber that exploits 'anything but bad workmanship' to achieve a very highly effective, if a bit complex to construct, absorber.

Oh, and I assume one is also aware of the recent definitive studies regarding the significant effect of edge diffraction in both absorption and diffusion, sufficient to throw a wrench into ASTM-C423, ISO-354 as the results "calculated using the methods recommended in ASTM-C423 and ISO-354 may be inaccurate at best", expressing as a litote connoting the extreme understatement!!!!, as well as also requiring modification to "methods of measuring scattering coefficients suggested in ISO-17497-1".

And in case someone is wondering why I am bringing up the 200 Hz cut-off...

http://soundfieldaudio.net/Products.html

....and the 1/12th Oct. Btw, hows that buy-wiring working out for you?

Ah, come on!

You know how hard it is to get that woofer to stand still when making a measurement?

Of course its going to vary when it keeps trying to move all around!

1/6 or 1/12 octave smoothing!?!?!?!?! Heck, if you applied either smoothing to a person's activity, they could go to the store and return and then assert, by virtue of the measurement, that they never left!

But its GREAT when you want to hide something!

So you obviously have level 4 that is also capable of 1/24.

So you can show 200 Hz and up with a bit more resolution, or full range at a reduced resolution... but not both at the same time?

How would in room full range at 1/24 look?

This thread funny. Wait...?

You (or your associate) are not much of a designer, are you.
It's up to the designer's skill to be able to convince the client to accept the optimum performance as the choice of the appearance. Too bad it turned out the way it did. I wouldn't show off the picture of that project like a trophy if I were you.

Well, you know what? We did try that tactic first. But it didn't work. Seems that folks don't want to buy stuff like this:



Thanks for that post Dio. It was fun to wake up to it .