EnABL - Technical discussion

[markus76]

Originally Posted by planet10

I could loan speakers given sufficient lead time, i do not have the space, time, or any funds.

dave

You should sell cables. Brings in more money than drawing dots onto speakers

[markus76]

Originally Posted by ra7

Btw, in the link from Bud (below), the scale between the two CSD plots is vastly different:
EnABL Processes

Quite honestly, those CSD graphs look like someone had a hard time using his measurement gear and software.

[planet10]

Originally Posted by markus76

You should sell cables.

Too much snake oil. I do the spots because it 1st off allows me to get closer to the music.

dave

[tuxedocivic]

Dave, 30 to 50db down in a home at night is easy to achieve. But what parameter is it you'd want to find? Phase, CSD, frequency response, distortion, etc. It's not HOM...

Based on the (little) data that is out there, I think it's spreading out break up at high frequencies. Which the audible effects can be 30 to 50db down and related to CSD. That's my guess. If you can lower the q of break up peaks and shut down the ringing a little, then it probably sounds better / clearer. You might hear the music better.

[planet10]

Originally Posted by tuxedocivic

30 to 50db down in a home at night is easy to achieve.

Now how do you extract that information in the presence of the stimulating 0dB signal? And a typical room does not give you the time dimension you really need to capture the information.

phase, CSD, frequency response, distortion, etc. It's not HOM

All of them. And if you reduce HOMs, by definition you are increasing DDR.

And what do you mean by distortion. Better DDR means lower distortion -- but in its broadest term, not the ususal, and near useless THD often measured & equated with the term distortion.

then it probably sounds better / clearer. You might hear the music better.

Clearer is a good word. A visual analogy that i have used in the past, is imagine looking down onto a mountain valley with a mist that prevents you from making out small details... then EnABL would be having the sun come out and clear away the mist allowing you to see in greater detail what is down there.

dave

[tuxedocivic]

Well if you need to capture information beyond say 3ms, then a typical room couldn't do that. Still, outside at night can be very silent, might work. The software extracts the information. But you need to know what you're trying to measure.

I'm not sure a direct radiator has a HOM issue??? Might want to check with Geddes on that. My understanding of HOM is that it's a reflection in the horn throat (simplified explanation).

By distortion, I measure non-linear distortion like 2nd, 3rd, 4th, etc. Those can be easily measured. No, I wouldn't just measure THD. You need to see them individually and at various frequencies.

But distortion comes in various linear forms also, but a frequency response can mostly quantify those.

[planet10]

Originally Posted by tuxedocivic

Well if you need to capture information beyond say 3ms, then a typical room couldn't do that. Still, outside at night can be very silent, might work. The software extracts the information. But you need to know what you're trying to measure.

You need to be somewhere where you can eliminate the need to window anything.

As a simple example, as a stimulas use a 0dB signal with a -x0 dB riding on top. You want to extract the FR of the -x0 dB signal.

With a CSD, i want to know what is happening -x0 dB under that 1st curve at 0ms and the CSD that that gives.

I'm not sure a direct radiator has a HOM issue???

It may or may not, but in a device that coule produce HOMs, if you can eliminate them you increase DDR

By distortion, I measure non-linear distortion like 2nd, 3rd, 4th, etc

Those are pigeon holes. By distortion i mean anything that is adding or subtracting information to the signal. Most distortion measurements look for stuff that is added and not those that are subtracted.

Linear refers to that 5% of mathematical problems that can be solved simply (and what science has concentrated on up until the disemination of chaos/information theory. Non-linear distortion is the 95% of problems. The very term non-linear means that it is being looked on from the comfortable point of view that comes from solving linear problems. Information theory brings a more holistic POV. Think in terms of what information id lost or corrupted.

dave

[planet10]

Another discussion of DDR starting about here Future woofer production

dave

[tuxedocivic]

By nonlinear I mean harmonic distortion, sorry to confuse. If that isn't what needs to be measured that's fine by me.

Hmm, the first part of your reply is interesting, and doable. I'm not sure how many measurement software packages are equipped to do it, but most have an RTA. Then input a say 1000hz signal at 0db with a 5000hz at -10db and a 4200hz at -20db etc. all random. Then snap an RTA. Do it in a very dead space. Large quite room with thick mats of insulation all around (I have lots). Then do another set of ransoms. Do about 30 different randomness for each speaker (enabled an non). If the non enabled speaker doesn't produce the signals below the main 0db signal as strongly as the enabled speaker, perhaps you've found the difference.

[planet10]

A good place to start to get a feel for it, but very 1 dimensional/simplistic.

Ideally 20-20k at 0 dB with another 20-20k at -x0 dB. since you are looking for a "flatness" of the entire spectrum.

dave