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Audibility thresholds of amp and DAC measurements

luft262

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Where could I find a brief and simple guide that explains each of the tests and what they mean? Thanks.
 
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flipflop

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wwenze

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I should try recording the output from a China TDA1543 DAC that measures around 0.3% IIRC. Any nomination for the music?
 

S34MH1

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In 'Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms' Floyd Toole says the following: "The simplest deviation from flat is probably a spectral tilt. There is some evidence that we can detect slopes of about 0.1 dB/octave, which translates into a 1 dB tilt from 20 Hz to 20 kHz — not much."

"If the FR rises by 0.05 dB in one area and drops by 0.05 dB in another, the total discrepancy will be 0.1 dB."

Frequency response: ±0.05dB
Channel balance: 0.1dB

Am i right?
 

Robbo99999

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In 'Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms' Floyd Toole says the following: "The simplest deviation from flat is probably a spectral tilt. There is some evidence that we can detect slopes of about 0.1 dB/octave, which translates into a 1 dB tilt from 20 Hz to 20 kHz — not much."

"If the FR rises by 0.05 dB in one area and drops by 0.05 dB in another, the total discrepancy will be 0.1 dB."

Frequency response: ±0.05dB
Channel balance: 0.1dB

Am i right?
(Is that anything to do with this thread? Not read back through the pages)

But he's talking about a 1dB tilt all the way from 20Hz to 20kHz being audible, not a 0.1dB tilt across that same range. And you're only going to hear those differences if it's a consistent tilt, not just some random +/-1dB variation across the whole range.
 

BYRTT

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(Is that anything to do with this thread? Not read back through the pages)

But he's talking about a 1dB tilt all the way from 20Hz to 20kHz being audible, not a 0.1dB tilt across that same range. And you're only going to hear those differences if it's a consistent tilt, not just some random +/-1dB variation across the whole range.

He said "0,1dB/octave" and that's not same as 0,1dB tilt across that same range :) 0,1dB/octave arrive at a 1dB difference @20Hz/20kHz..

Robbo99999.png
 
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Robbo99999

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He said "0,1dB/octave" and that's not same as 0,1dB tilt across that same range :) 0,1dB/octave arrive at a 1dB difference @20/20kHz..

View attachment 143140
Yeah, that's cool, I understand that (already). But I don't see how it relates to amp specs for the other points I highlighted in my previous post, ie +/-0.05dB in an amp spec is gonna mean random variation across the whole spectrum from 20Hz-20000Hz - so that's not a "tilt" phenomenon (and certainly not in reference to over an octave). So @S34MH1 is comparing apples to oranges.
 
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