DIY measurement data...Archive or Delete?

[moldyoldy]

zzzzzzzzzP! Last one. Save as. Load and post-process. Enter test specifics. Save again.

Sound familiar?

Ever test an item "just passing thru" simply because you had the chance?

How many saved files have you deleted?

How many have you published?

I've just been trying to grok the current volume of DIY test data already occupying the hard drives of the world. The growing software business appears to be thriving. Screenshots are replacing LOLs more every day.:hmm:

Wouldn't it be nice to gather all that data in a searchable database?

Or would it...? If I wasn't fully confident in my findings, why the hell should you be? What if you meant well, but just got it wrong? Is none better than bad?

Is there a way to set a standard, take a test, and become "certified" as competant plot publisher, both for your own confidence, as well as the public's?

[Robh3606]

The problem with measurements is they are only valid for the conditions they are taken under. The baffle, internal volume, stuffing used are all going to effect things not to mention microphone distance and a how the measurements are windowed and so on. That kind of limit's their usefulness.

To be honest I have thought about building a DIY measurement archive but it's usefulness is really kind of limited. It's more for general information than anything else. In that way it could be useful especially if they are from different sources and they match a different set from another source. If they don't which ones right?? The JBL driver and system measurements we have are the real deal. It's great we have a decent sized library of them.

The DIY FR/Impedance plots are useful as you work things out to see if your changes are going in the direction you want but that's about it. They can give trends and will give you a good idea of what a driver will do on a horn as an example but they are not averaged over a systems listening window. These are simple one point in space measurements which limits what they tell you. It could look great at one point in space and have a hole in my response an octave and a half wide 2 ft higher or left or right from a combination of baffle placement and crossover issue and I would never see using just that "Point and Shoot" measurement technique.

Sure I could hear it easy enough using the old reliable Stand Up Sit Down Test. There is just no substitute for common sense and using your ears.


Rob:)

[moldyoldy]

Thanks, Rob.

I agree that much of what we test is aimed at very user-specific applications, but who's to say someone else isn't considering the same thing, and would find that data useful? Perhaps if there was a standardized template to enter the requisite data in, finding and interpreting relevant info could be simplified.

True that JBL has done an excellent job of publishing reliable data, but only for factory apps, and given the nature of DIYers to implement non-typical variations, there's more to be had. Altec users aren't quite as lucky in those regards...:(

I think most of the measurement systems we use are very capable of reliable, detailed results when properly calibrated and deployed, and limited mainly by the skills of the user.

I'm not trying to take this anywhere in particular, just wondering what others thoughts were. I can't help but feel if done properly, a valuable resource for the community could implemented.

Alternatively, without an organized effort to set some standards, I expect to see an increasing number of published plots scattered thru the ether, often missing important variables, and of unknown reliability. In that scenario, I wonder if having no info wouldn't be better...

[Robh3606]

I'm not trying to take this anywhere in particular, just wondering what others' thought were. I can't help but feel if done properly, a valuable resource for the community could implemented.


Understood:)

I basically agree as long as you understand the limitations of the information provided it has potential to add some useful information.


Alternatively, without an organized effort to set some standards, I expect to see an increasing number of published plots scattered thru the ether, often missing important variables, and of unknown reliability. In that scenario, I wonder if having no info wouldn't be better...

Well I am not sure no information at all is better. Your right though without some form of standards you have no way to compare unless you know what the measurement conditions were and have enough experience to understand how the differences effect the measurements. No easy task for the average armchair enthusiast.

Rob:)

Your average armchair enthusiast:blink:

[Zilch]

My measurements have more meaning and utility to me, because I am familiar with the context and methods I use, and it's not likely I'm going to do any serious design work without measuring the devices myself. However, I think there's merit in having data from independent sources available as well.

Does everyone get the same T-35 curve? Do 811B and 511B measure the same? Do 806As crash universally? Is my flat the same as your flat?

At a certain point, it becomes statistical. Can I have confidence in my results taken on but a couple of drivers? I'm feeling much better about what I do if it's confirmed by results obtained independently by others. :yes:

[moldyoldy]

Exactly. Only better really, cause it works both angles, i.e. archival, and inter-active training for all. Instead of having to follow a guideline, participants would learn to get it right by doing it interactively. No shame, no need to sit on all those files. There WILL be boo-boos, users will learn to recognize them and how to correct them.

For a baseline, you could select a widely-available, inexpensive, wide-range speaker of known response (and consistent production). After a number of files are submitted of the base unit, trends should emerge. Comparison will lead to perfection of technique.

Grandma always said, "people make mistakes, fools make the same one twice", wherupon Grandpa would respectfully add, "and smart folks don't hafta make no mistakes 'tall, if'n they seen somebody else do it first".

What's needed is an application to accept, integrate, and manage the data, ideally, in an active, "intelligent" manner that allowed comparison of multiple files in a web-based "universal" UI (dealing with all the files as screenshots would drive ya nuts). An immediate challenge would be the multitude of proprietary filetypes to deal with. There may be an out there, as all the routines I've used had the ability to save as a text file. If that's a common denominator to all, and if there's no data loss that way, it shouldn't take too much of a web app to archive and display (perhaps more) the files. (That's awfully easy for me to say, as I know nothing about web apps!)

Too ambitious?