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The only way I can think of to change the frequencies emitted by a recording is to change the speed (clock rate for digital, tape speed, or RPM for vinyl) of playback.
With music, all frequencies would be affected equally, the relative frequencies remain the same (an octave is still an octave, a fifth a fifth) and with this small an error, undetectable except by metered test. (@JustIntonation might disagree)
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I made a test once of frequency precision and while other had always error i was always 100÷ precise.
I had to turn a knob to obtain same frequency as the one i was listening i my score was always 0.00 difference with what i heard. Lot of people couldn't get 0 error.
So i believe i hear differences between frequencies very precisely. That's why i care about that.
Do the test Ray described, using a blind DBT tool, e.g. foobar, post the results.
Comparing the two test tones back to back, you might hear a difference.
Listening to the two tones simultaneously will create a 2Hz beat.
Listening to two different musical recordings, one with, and one without that amount of error, I don't think so.
Listening to the two tones simultaneously will create a 2Hz beat.
Listening to two different musical recordings, one with, and one without that amount of error, I don't think so.
Easy and quick in just about any DAW out there (even I can do it). Faster than typing stuff on a forum.
But as @Soniclife says, the comparison MUST be done double blind to have even the slightest significance.
With the two tones in Audacity:
Switching from one to the other (solo button), I don't detect a change in frequency.
I do detect a slight change in amplitude - move head to modify extent of comb filtering affecting the perceived SPL- two speakers, reflections present.
Playing both tones simultaneously, an obvious yowyowyow as they combine and cancel.
Switching from one to the other (solo button), I don't detect a change in frequency.
I do detect a slight change in amplitude - move head to modify extent of comb filtering affecting the perceived SPL- two speakers, reflections present.
Playing both tones simultaneously, an obvious yowyowyow as they combine and cancel.
Headphones make more sense for these sorts of tests, to avoid the chaos of speakers in rooms making things complicated.
Yes, but I rarely use them for listening, so...
I did for one test before:
Like 1000Hz in left channel, 1002 in the right.
Beating occurs as the frequencies are combined in your head, not in the air. I thought it amusing.
If over sampling can not make some error on precision of frequency?
My DSP moves everything to 48khz sample rate.
My DAC moves everything it receives to a 211Khz sample rate.
Then there's this unfathomable description:
CONCEPTUAL OVERSAMPLING
The digital filters in the DAC2 operate at a conceptual sample rate of about 250 GHz. Incoming audio is conceptually upsampled to 250 GHz and then down sampled to 211 kHz using a filter that mathematically behaves as if it is operating at a 250 Giga-sample-per-second rate. We use the word "conceptual" because the calculations and internal clocks are not actually running at 250 GHz. Due to the mathematics of upsampling, most of the filter calculations require a multiply by zero operation. These unnecessary zero-product calculations are eliminated while all of the non-zero calculations are executed. The net result is mathematically equal to the results that would have been produced by executing every calculation at a 250 GHz sample rate. Eliminating the unnecessary calculations reduces the DSP and processing rates to a manageable load.
I don't worry about it.
No. Our ears aren't sensitive to that actual pitch.
That's actually for frequency modulations, not just slowing or speeding down the frequency as is being discussed. Our absolute pitch accuracy is quite poor and far worse than that. Years back studios would release VHS tapes in Europe PAL system as sped up 24 Hz to 25 frames per second of that video format. While some folks would notice that, clearly the mass market did not and that is a heck of a lot of pitch error.
Some people were really bothered by that, I was only bothered after I heard what it sounded like at the correct speed, once I heard that there was no going back to wrong. DVD was the same.
I kept reading to find the part that's relevant to the discussion. If I'm quoting the correct passage this time, it seems to be contradicting you:
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Unlike simultaneous and forward masking though, this is an area in which there is massive variation from human to human, it should be noted
That is a differential test, not steady-state as we are discussing. Our DAC aren't jumping up and down in speed that way.
BTW, the case was stated incorrectly. The error is much less than that. Here is an example:
That is .05 Hz error, not 5 Hz. So definitely a non-issue.
Unverifiable Anecdote:
Audio Buddy brought over a CD made from a cassette recorded on a boom-box in some dimly lit club featuring dimly visible performers (he was the Token Caucasian in the band) and sometime way back when in the Baltimore/DC area, played back and ripped from his Nakamichi.
It was rough, but listenable, and band was tight and the tunes were fun. The leader/singer played an irrationally exuberant B3.
I thought it sounded off-key.
My CD player has a speed control, I tuned it to my ear, and said "There!"
We argued about it a little, so since he played it, and remembered the key and notes, we put a tuning frequency up on the PC speakers and compared to the adjusted playback.
The frequency (and due to that, the tempo) adjustment was perfect.
(just one of those things that you can't do again, though @JustIntonation might)
Audio Buddy brought over a CD made from a cassette recorded on a boom-box in some dimly lit club featuring dimly visible performers (he was the Token Caucasian in the band) and sometime way back when in the Baltimore/DC area, played back and ripped from his Nakamichi.
It was rough, but listenable, and band was tight and the tunes were fun. The leader/singer played an irrationally exuberant B3.
I thought it sounded off-key.
My CD player has a speed control, I tuned it to my ear, and said "There!"
We argued about it a little, so since he played it, and remembered the key and notes, we put a tuning frequency up on the PC speakers and compared to the adjusted playback.
The frequency (and due to that, the tempo) adjustment was perfect.
(just one of those things that you can't do again, though @JustIntonation might)
