ISeekTheTruth
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Perhaps between neighboring bits of the same word. Still wondering about the __ db? above
One last clarification. on dither and tearing. I am seeing posts that each bit ? has 6dB of dynamic range. There must be some context to this blanket statement.
View attachment 201171
Close enough that most people say 6 dBOne last clarification. on dither and tearing. I am seeing posts that each bit ? has 6dB of dynamic range. There must be some context to this blanket statement.
View attachment 201171
Guess this diagram is not very clear. What I meant was if we had a sine wave having a + and - 0000 0000 0000 0001 above and below zero. How loud would that be in dB compared to 0dB. ie how large is the noise created by dither in dB when moving from 24 bit to 16 bit?
Tearing is the sound made due to bit reduction without dither on a fade out.
It depends on the exact dither implementation and how you measure it, but in a nut shell, typically ± half bit (the target lsb), or a peak-to-peak amplitude of 1 lsb. That would be -90 dBFS for 16-bit, for instance. But it might make more sense to spec it as RMS, which would be about 3 dB less, ~93 dB.Guess this diagram is not very clear. What I meant was if we had a sine wave having a + and - 0000 0000 0000 0001 above and below zero. How loud would that be in dB compared to 0dB. ie how large is the noise created by dither in dB when moving from 24 bit to 16 bit?
Just wanted to know how loud in db 0000 0000 0000 0001 (16 bit) was above 0dB same for24 bit. 0000 0000 0000 0000 0000 0001 Tearing is the sound made due to bit reduction without dither on a fade out.
Not all dB are the same "size"...
Bigger dB are bigger than smaller dB.
Doubling a large voltage may take the resulting sound from too loud to excruciating.
Doubling a tiny voltage may not even be noticeable.
The reference for digital signals is a full scale signal. Such signal is at 0 dBFS.Just wanted to know how loud in db 0000 0000 0000 0001 (16 bit) was above 0dB same for24 bit
This seems like an insane unit to use regularly then. Is there a distinguishing addition to the dB unit that is dropped for "convenience" because it seems like there are a lot of dB units used in Electro-Audio that aren't interchangeable?
It is no more or less "insane" than logarithmsThis seems like an insane unit to use regularly then.
"dB" on its own is a measure of a ratio between any two signals.Is there a distinguishing addition to the dB unit that is dropped for "convenience" because it seems like there are a lot of dB units used in Electro-Audio that aren't interchangeable?
Decibels, being a ratio of dimensioned quantities, are unitless.
The irregularity ("not all the same size") stems from a dB being a logarithm, which is non-linear.
At least, I think that is what Ray meant?
it seems that I'm not alone in the confusion it causes
I just skimmed the Wikipedia page on Decibels and it seems that I'm not alone in the confusion it causes because it can be a relative or absolute reference, of different logarithmic bases, that may or may not be attached to different actual units (that are often unwritten because they are understood within the context of the industry using them).
I understand why you say that, but better to realize It's always relative. It might be relative to what it was before ("the mix is getting close, but the kick is too loud—try dropping the kick 4 dB"), it might be to the maximum possible ("the peaks are running hitting -2 dB"—that can be a little vague, so it's best to say -2 dB FS or full scale, if that's what you mean), or an agreed reference level ("the output of this preamp can attain +18 dBu").I just skimmed the Wikipedia page on Decibels and it seems that I'm not alone in the confusion it causes because it can be a relative or absolute reference, of different logarithmic bases, that may or may not be attached to different actual units (that are often unwritten because they are understood within the context of the industry using them).
Yes, that's a pretty good summation. On converters being hard pressed to get much beyond 20 bits:So the 6db approximate difference between adjacent bits in a 16 or 24 bit word makes sense. so the difference between 0000 0000 0000 0001 and 0000 0000 0000 0010 would be around 6 dB. I guess my original thought was in this post that 0dB was the base reference for the threshold of hearing. As you have indicated I should have been using full scale signal as my base reference for dB. Then your numbers of around -90 and -138 for a least significant bit toggle in a 16 bit or 24 bit word respectively make some sense. So as a passing comment, the noise added by dither IS extremely small. I also read that DA converters running at 24 bit are hard pressed to reproduce analog faithfully beyond 20 bits. Not sure if that is true or relates to the delivery to the air at the end of the day.