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Time/Phase Alignment, Acoustic Center, Lobing etc. - new tech note from Purifi

IPunchCholla

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The fact that we have a concept of color gamut, and well defined perceptual metrics to transform one gamut into another, speaks to the maturity and effectiveness of visual science compared to audio. Imagine if we could translate the 'control room' audio into 'headphone' audio as well as we can translate pigments into light.
Absolutely! But it is interesting how even being far more advanced, there is still a circle of confusion (though much smaller than audio’s). Even running very good color calibrated monitors using custom built profiles, getting the print you want at the level of exactitude we pursue, is a matter of trial and error. I still have to print test strips! And adjust accordingly.

The science is pretty much solved for the issues of inkjet printing, both technically and perceptually, but the engineering is still lagging a small amount.

This seems similar to audio. Outside of transducers, the engineering in audio seems to have surpassed audibility thresholds for even trained listeners. But in my brief scanning of the literature of psychoacoustics, the individual elements of how hearing works is pretty well understood, the variability of populations and variability of individuals through time is much less so. And there seems to be a lack of synthesis to be able to get to parity with being able to consistently transform experiential modes, mostly due to the increased complexity of the reproduction system interacting with the space of experience.
 

gnarly

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This is misleading, at best. First off, you can’t define it the way you have, so I doubt the best science grad schools ever said such a thing. If you’re going to define resolution by inches you have to do so for a particular viewing distance. Secondly, we have had ways of creating high resolution images (far higher than inkjet printers, for a very long time, so the better printers leading to better tests is probably apocryphal.
Yep, the visual parallel lacked all kinds of details such as viewing distance...and was only meant to get people to question the audible resolving power of todays' speakers, in the context of how much detail are they even capable of, compared to the detail we can hear in nature.

Back in the 90's when digital photography was moving into pro DSLRs, and megapixel counts were beginning to climb, a big camp argued that for a given size print and a given viewing distance, once a certain amount of megapixels were in play, any further resolution was wasted because the eye couldn't resolve further.
That limit was often quoted at whatever MP count equated to 200-300 lpi. I have some science buds who went to top drawer undergrad and grad schools here in the US , who were also into photography at the time and asked them if they'd ever heard of that 200-300 lpi limit....they said yeah, comes from the books citing RAF and US AirForce studies trying to determine minimal/maximal resolution needed for aerial photos. Anyay, just saying I didn't make it up ...and thought you might find it interesting :)

And for printers....oh lord, glad im done learning about them....got involved too deep with identity document verification/authentication for a while.
 

gnarly

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I agree we shouldn't throw up our hands and quit! My point is that chasing after engineering metrics is not going to work.



This 'scientism' isn't limited to boutique audiophile companies making speakers covered in lacewood veneer, it's also the most advanced outfits. I love what Genelec has done with cardioids and their most recent speaker is incredible - but is it a step forward in audibility? I see no evidence that it is. It probably sounds incredibly impressive, but I bet a Westlake Audio system does too.
Well, all I can say chasing engineering metrics is working for me....I'm defintely getting clearer sound and better transients chasing engineering.

and it seem to be working for the likes of Neuman, Genelec, Meyersound, Danley Sound Labs, Fulcrum Acoustics.....heck, most of the prosound world...
 

restorer-john

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It is a good tool though, to find the sweetspot of your speakers ;) Where you’ll find the perfect square wave, you’ll have perfect time alignment.

Only if your tweeters are still working...
 

tmtomh

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Eagerly awaiting the launch of sister site AudioSquareWaveReview.
 
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