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The invention of measurements and perception

This is going to be pretty airy-fairy. Sorry.

Let’s talk about how measurements get invented, and how this limits us.

One of the great works of engineering, science, and data is finding signals in the noise. What matters? Why? How much?

My background is in computer science, and a little in electrical engineering. So the question of what to measure to make systems (audio and computer) "better" is always on my mind.

What’s often missing in measurements is "pleasure" or "satisfaction."

I believe in math. I believe in statistics, but I also understand the limitations. That is, we can measure an attribute, like "interrupts per second" or "inflamatory markers" or Total Harmonic Distortion plus noise (THD+N)

However, measuring them, and understanding outcome and desirability are VERY different. Those companies who can do this excel at creating business value. For instance, like it or not, Bose and Harman excel (in their own ways) at finding this out. What some one will pay for, vs. how low a distortion figure is measured is VERY different.

What is my point?

Specs are good, I like specs, I like measurements, and they keep makers from cheating (more or less) but there must be a link between measurements and listener preferences before we can attribute desirability, listener preference, or economic viability.

What is that link? That link is you. That link is you listening in a chair, free of ideas like price, reviews or buzz. That link is you listening for no one but yourself and buying what you want to listen to the most.

E
erik_squires
erik_squires OP
5,268 posts
 
I'd like to move this a little more forward:
@spatialking wrote:


I can tell you the reason we have jitter problems, besides the fact that the basic CD clocks are not all the accurate,

Clocks are much better now than they were before at the same price range.  Maybe this is why DAC's got magically better?



is the sample clock is encoded in the data stream.   The clock is not a
separate signal path from the data which makes jitter an inherent problem in the system.  

I think maybe this is the transmission method, not the data. I think the issue is who is in charge though. I2S and USB allow the DAC to be in charge of the clock.
erik_squires OP
5,268 posts
 
Here’s a blast from the past : Sonic Frontiers may have been the only one’s I know of to expose I2S outside of a CD player:


https://www.stereophile.com/content/sonic-frontiers-transport-3-cd-transport-processor-3-da-processo...

jea48
2,944 posts
 
onhwy614,133 posts12-31-2018 2:18pmjea48, aren’t microphones and tape recorders essentially measurement devices/test equipment?
Not to me.

I don’t believe that is the intent of the OP’s posting of this thread either. I could be wrong though.....I’ll let erik_squires speak for himself.

Now are there instances where a microphone is used for setting the levels of equipment, (example home theater systems), sound levels then the answer is yes.
I guess there could be examples where a microphone might be used for a listening test but isn’t that like getting the info 3rd hand? I mean the only true way to hear how Jennifer Warnes voice sounds would be to hear her sing without any microphone/s or electronic sound equipment.


As to my previous post I would appreciate an honest response. To clarify.... Do you think there is "bench test equipment" that can measure fullness and timbre differences between that of two amplifiers that the human ear can hear of a recording of Jennifer Warnes?

Jim

nonoise's avatar
nonoise
4,382 posts
 
Nope.
erik_squires OP
5,268 posts
 
jea48, aren't microphones and tape recorders essentially measurement devices/test equipment? If it wasn't for these measurement devices would you even know what the timbre of a performance were?

At least for the intentions of this thread, no. They are recording devices.

A measure is a number. So what I meant to talk about here is that a number, like signal to noise (S/N) by itself has no real meaning in terms of desirability.
We, humans, use these to tell us a little about the equipment and signal quality, and we must give that number meaning.

For instance, one amp at 1 watt has a S/N ratio of 90 dB.

How much better is it than 900 dB? I mean, yes,we can do math and express this in volts, but is it now at the point of ridiculous? Would you pay 10x as much? Could you hear it?

Numbers are great for automating testing, and creating manufacturing standards. They also validate whether or not we are making a meaningful change, but ultimately there's a separate step where we must ascribe value and perception to it.

Best,
E

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