On 6 February 2015 at 12:16, Didier Dambrin <di...@skynet.be> wrote: > I'm not quite sure I understand what you described here below. > I think the wavs should have contained a normalized part, so that anyone who > listens to it, will never crank up his volume above the threshold of pain on > the first, normalized part, and then everyone is more or less listening to > the quiet part the same way.
That is exactly what I was doing, to normalise the float wav file and let you know it wasn't even remotely near the level of pain, which tells me the gain of -12 dB on the headphone amp is a reasonable listening level. > Claiming that it's any audible is one thing, but you go as far as saying > it's clear to hear.. we're probably not testing the same way. > I have normalized (+23dB) the last 9 seconds of the Diva bass 16-bit > truncated.wav file to hear what I was supposed to hear. I'm just not hearing > anything close to that, in the normal test. I can only say what I hear, which is pretty clear. Nigel's point about the volume is this: at one point in the song that bass sound would be normalised up higher, or perhaps behind drums which were louder, but you can consider this bit as being in a quieter bit of a song, so absolutely reasonable as a test case. > While I have Sennheiser HD650, I'm listening through bose QC15 because, > although it's night time, my ambient noise is probably a gazillion times > above what we're debating here. So I'm in a pretty quiet listening setup > here (for those who have tried QC15's). If you can't hear it I believe you, but I can hear it. Not all peoples hearing is equal. All the best, Andrew Simper > > > > -----Message d'origine----- From: Andrew Simper > Sent: Friday, February 06, 2015 3:31 AM > > To: A discussion list for music-related DSP > Subject: Re: [music-dsp] Dither video and articles > > I also tried boosting the float version of the bass tone to -1 dB (so > another 18 dB up from with the same test setup), it was loud, but not > anywhere near the threshold of pain for me. I then boosted it another > 12 dB on the headphone control (so 0 dB gain), so now 30 dB gain in > total and my headphones were really shaking, this was a bit silly a > level, but still definitely not painful to listen to. My point being > that this is a very reasonable test signal to listen to, and it is > clear to hear the differences even at low levels of gain. > > If I had to choose, between the two 16-bit ones I would prefer the one > with dither but put through a "make mono" plugin, as this sounded the > closest to the float version. > > All the best, > > Andy > > -- cytomic -- sound music software -- > > > On 5 February 2015 at 16:46, Nigel Redmon <earle...@earlevel.com> wrote: >> >> Hmm, I thought that would let you save the page source (wave file)…Safari >> creates the file of the appropriate name and type, but it stays at 0 >> bytes…OK, I put up and index page—do the usual right-click to save the field >> to disk if you need to access the files directly: >> >> http://earlevel.com/temp/music-dsp/ >> >> >>> On Feb 5, 2015, at 12:13 AM, Nigel Redmon <earle...@earlevel.com> wrote: >>> >>> OK, here’s my new piece, I call it Diva bass—to satisfy your request for >>> me to make something with truncation distortion apparent. (If it bother you >>> that my piece is one note, imagine that this is just the last note of a >>> longer piece.) >>> >>> I spent maybe 30 seconds getting the sound—opened Diva (default >>> “minimoog” modules), turn the mixer knobs down except for VCO 1, set range >>> to 32’, waveform to triangle, max release on the VCA envelope. >>> >>> In 32-bit float glory: >>> >>> http://earlevel.com/temp/music-dsp/Diva%20bass%2032-bit%20float.wav >>> >>> Truncated to 16-bit, no dither (Quan Jr plug-in, Digital Performer), >>> saved to 16-bit wave file: >>> >>> http://earlevel.com/temp/music-dsp/Diva%20bass%2016-bit%20truncated.wav >>> >>> You’ll have to turn your sound system up, not insanely loud, but loud. (I >>> said that this would be the case before.) I can hear it, and I know >>> engineers who monitor much louder, routinely, than I’m monitoring to hear >>> this. My Equator Q10s are not terribly high powered, and I’m not adding any >>> other gain ahead of them in order to boost the quiet part. >>> >>> If you want to hear the residual easily (32-bit version inverted, summed >>> with 16-bit truncated, the result with +40 dB gain via Trim plug-in): >>> >>> >>> http://earlevel.com/temp/music-dsp/Diva%20bass%2016-bit%20truncated%20residual%20+40dB.wav >>> >>> I don’t expect the 16-bit truncated version to bother you, but it does >>> bother some audio engineers. Here's 16-bit dithered version, for >>> completeness, so that you can decide if the added noise floor bothers you: >>> >>> http://earlevel.com/temp/music-dsp/Diva%20bass%2016-bit%20dithered.wav >>> >>> >>> >>>> On Feb 4, 2015, at 1:10 PM, Didier Dambrin <di...@skynet.be> wrote: >>>> >>>> Yes, I disagree with the "always". "Not always needed" means "it's >>>> sometimes needed", my point is that it's never needed, until proven >>>> otherwise. Your video proves that sometimes it's not needed, but not that >>>> sometimes it's needed. >>>> >>>> >>>> >>>> -----Message d'origine----- From: Nigel Redmon >>>> Sent: Wednesday, February 04, 2015 6:51 PM >>>> To: A discussion list for music-related DSP >>>> Subject: Re: [music-dsp] Dither video and articles >>>> >>>>> I totally understood the point of your video, that dithering to 16bit >>>>> isn't always needed - but that's what I disagree with. >>>> >>>> >>>> Sorry, Didier, I’m confused now. I took from your previous message that >>>> you feel 16-bit doesn’t need to be dithered ("dithering to 16bit will never >>>> make any audible difference”). Here you say that you disagree with >>>> "dithering to 16bit isn't always needed”. In fact, you are saying that it’s >>>> never needed—you disagree because “isn’t always needed” implies that it is >>>> sometimes needed—correct? >>>> >>>> >>>>> On Feb 4, 2015, at 5:06 AM, Didier Dambrin <di...@skynet.be> wrote: >>>>> >>>>>>> Then, it’s no-win situation, because I could EASILY manufacture a bit >>>>>>> of music that had significant truncation distortion at 16-bit. >>>>> >>>>> >>>>> Please do, I would really like to hear it. >>>>> >>>>> I have never heard truncation noise at 16bit, other than by playing >>>>> with levels in a such a way that the peaking parts of the rest of the >>>>> sound >>>>> would destroy your ears or be very unpleasant at best. (you say 12dB, it's >>>>> already a lot) >>>>> >>>>> I totally understood the point of your video, that dithering to 16bit >>>>> isn't always needed - but that's what I disagree with. >>>>> >>>>> >>>>> >>>>> -----Message d'origine----- From: Nigel Redmon >>>>> Sent: Wednesday, February 04, 2015 10:59 AM >>>>> To: A discussion list for music-related DSP >>>>> Subject: Re: [music-dsp] Dither video and articles >>>>> >>>>> Hi Didier—You seem to find contradictions in my choices because you are >>>>> making the wrong assumptions about what I’m showing and saying. >>>>> >>>>> First, I’m not steadfast that 16-bit dither is always needed—and in >>>>> fact the point of the video was that I was showing you (the viewers) how >>>>> you >>>>> can judge it objectively for yourself (and decide whether you want to >>>>> dither). This is a much better way that the usual that I hear from people, >>>>> who often listen to the dithered and non-dithered results, and talk about >>>>> the "soundstage collapsing" without dither, “brittle” versus >>>>> “transparent" , >>>>> etc. >>>>> >>>>> But if I’m to give you a rule of thumb, a practical bit of advice that >>>>> you can apply without concern that you might be doing something wrong in a >>>>> given circumstance, that advice is “always dither 16-bit reductions”. >>>>> First, >>>>> I suspect that it’s below the existing noise floor of most music (even so, >>>>> things like slow fades of the master fader might override that, for that >>>>> point in time). Still, it’s not hard to manufacture something musical that >>>>> subject to bad truncation distortion—a naked, low frequency, >>>>> low-haromic-content sound (a synthetic bass or floor tom perhaps). Anyway, >>>>> at worst case, you’ve added white noise that you are unlikely to hear—and >>>>> if >>>>> you do, so what? If broadband noise below -90 dB were a deal-breaker in >>>>> recorded music, there wouldn’t be any recorded music. Yeah, truncation >>>>> distortion at 16-bits is an edge case, but the cost to remove it is almost >>>>> nothing. >>>>> >>>>> You say that we can’t perceive quantization above 14-bit, but of course >>>>> we can. If you can perceive it at 14-bit in a given circumstance, and it’s >>>>> an extended low-level passage, you can easily raise the volume control >>>>> another 12 dB and be in the same situation at 16-bit. Granted, it’s most >>>>> likely that the recording engineer hears it and not the end-listener, but >>>>> who is this video aimed at if not the recording engineer? He’s the one >>>>> making the choice of whether to dither. >>>>> >>>>> Specifically: >>>>>> >>>>>> ..then why not use a piece of audio that does prove the point, >>>>>> instead? I know why, it's because you can’t... >>>>> >>>>> >>>>> First, I would have to use my own music (because I don’t own 32-bit >>>>> float versions of other peoples’ music, even if I thought it was fair use >>>>> to >>>>> of copyrighted material). Then, it’s no-win situation, because I could >>>>> EASILY manufacture a bit of music that had significant truncation >>>>> distortion >>>>> at 16-bit. I only need to fire up one of my soft synths, and ring out some >>>>> dull bell tones and bass sounds. Then people would accuse me of fitting >>>>> the >>>>> data to the theory, and this isn’t typical music made in a typical >>>>> high-end >>>>> study by a professional engineer. And my video would be 20 minutes long >>>>> because I’m not looking at a 40-second bit of music any more. Instead, I >>>>> clearly explained my choice, and it proved to be a pretty good one, and >>>>> probably fairly typical at 16-bit, wouldn’t you agree? As I mentioned at >>>>> the >>>>> end of the video, the plan is to further examine some high-resolution >>>>> music >>>>> that a Grammy award-winning engineer and producer friend of mine has said >>>>> he >>>>> will provide. >>>>> >>>>>> ...and dithering to 16bit will never make any audible difference. >>>>> >>>>> >>>>> If you mean “never make any audible difference” in the sense that it >>>>> won’t matter one bit to sales or musical enjoyment, I agree. I imagine >>>>> photographers make fixes and color tweaks that will never be noticed in >>>>> the >>>>> magazine or webpage that the photo will end up in either. But I guarantee >>>>> you, there are lots of audio engineers that will not let that practically >>>>> (using the word in the original “practical" sense–don’t read as “almost") >>>>> un-hearable zipper in the fade go. If they know it’s there, and in some >>>>> cases they CAN actually hear it, with the volume cranked, you can tell >>>>> them >>>>> all day and all night that they are wasting there time dithering, because >>>>> listeners will never hear it, but they will want to get rid of it. And the >>>>> cost of that rash action to get rid of it? Basically nothing. Hence my >>>>> advice: Dither and don’t worry about it—or listen to the residual up close >>>>> and see if there’s nothing to worry about, if you prefer. >>>>> >>>>> >>>>>> On Feb 3, 2015, at 10:24 PM, Didier Dambrin <di...@skynet.be> wrote: >>>>>> >>>>>> Sorry, but if I sum up this video, it goes like this: >>>>>> you need dithering to 16bit and I'm going to prove it, then the video >>>>>> actually proves that you don't need it starting at 14bit, but adds "it's >>>>>> only because of the nature of the sound I used for demo". >>>>>> >>>>>> ..then why not use a piece of audio that does prove the point, >>>>>> instead? >>>>>> I know why, it's because you can't, and dithering to 16bit will never >>>>>> make any audible difference. >>>>>> It's ok to tell the world to dither to 16bit, because it's nothing >>>>>> harmful either (it only mislays people from the actual problems that >>>>>> matter >>>>>> in mixing). But if there is such a piece of audio that makes dithering to >>>>>> 16bit any audible, without an abnormally massive boost to hear it, I'd >>>>>> like >>>>>> to hear it. >>>>>> >>>>>> Andrew says he agrees, but then adds that it's important when you >>>>>> post-edit the sound. Yes it is, totally, but if you're gonna post-edit >>>>>> the >>>>>> sound, you will rather keep it 32 or 24bit anyway - the argument about >>>>>> dithering to 16bit is for the final mix. >>>>>> >>>>>> To me, until proven otherwise, for normal-to-(not abnormally)-high >>>>>> dynamic ranges, we can't perceive quantization above 14bit for audio, and >>>>>> 10bits for images on a screen (debatable here because monitors aren't >>>>>> linear >>>>>> but that's another story). Yet people seem to care less about images, and >>>>>> there's gradient banding all over the place. >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -----Message d'origine----- From: Andrew Simper >>>>>> Sent: Wednesday, February 04, 2015 6:06 AM >>>>>> To: A discussion list for music-related DSP >>>>>> Subject: Re: [music-dsp] Dither video and articles >>>>>> >>>>>> Hi Nigel, >>>>>> >>>>>> Isn't the rule of thumb in IT estimates something like: "Double the >>>>>> time you estimated, then move it up to the next time unit"? So 2 weeks >>>>>> actually means 4 months, but since we're in Music IT I think we should >>>>>> be allowed 5 times instead of 2, so from my point of view you've >>>>>> actually delivered on time ;) >>>>>> >>>>>> Thanks very much for doing the video! I agree with your recommended >>>>>> workflows of 16 bit = always dither, and 24 bit = don't dither. I >>>>>> would probably go further and say just use triangular dither, since at >>>>>> some time in the future you may want to pitch the sound down (ie for a >>>>>> sample library of drums with a tom you want to tune downwards, or >>>>>> remixing a song) then any noise shaped dither will cause an issue >>>>>> since the noise will become audible. >>>>>> >>>>>> All the best, >>>>>> >>>>>> Andrew >>>>>> >>>>>> -- cytomic -- sound music software -- >>>>> >>>>> -- >>>>> dupswapdrop -- the music-dsp mailing list and website: >>>>> subscription info, FAQ, source code archive, list archive, book >>>>> reviews, dsp links >>>>> http://music.columbia.edu/cmc/music-dsp >>>>> http://music.columbia.edu/mailman/listinfo/music-dsp >>>> >>>> >>>> -- >>>> dupswapdrop -- the music-dsp mailing list and website: >>>> subscription info, FAQ, source code archive, list archive, book reviews, >>>> dsp links >>>> http://music.columbia.edu/cmc/music-dsp >>>> http://music.columbia.edu/mailman/listinfo/music-dsp >>>> >>>> ----- >>>> Aucun virus trouvé dans ce message. >>>> Analyse effectuée par AVG - www.avg.fr >>>> Version: 2015.0.5645 / Base de données virale: 4281/9056 - Date: >>>> 04/02/2015 >>>> -- >>>> dupswapdrop -- the music-dsp mailing list and website: >>>> subscription info, FAQ, source code archive, list archive, book reviews, >>>> dsp links >>>> http://music.columbia.edu/cmc/music-dsp >>>> http://music.columbia.edu/mailman/listinfo/music-dsp >>> >>> >>> -- >>> dupswapdrop -- the music-dsp mailing list and website: >>> subscription info, FAQ, source code archive, list archive, book reviews, >>> dsp links >>> http://music.columbia.edu/cmc/music-dsp >>> http://music.columbia.edu/mailman/listinfo/music-dsp >> >> >> -- >> dupswapdrop -- the music-dsp mailing list and website: >> subscription info, FAQ, source code archive, list archive, book reviews, >> dsp links >> http://music.columbia.edu/cmc/music-dsp >> http://music.columbia.edu/mailman/listinfo/music-dsp > > -- > dupswapdrop -- the music-dsp mailing list and website: > subscription info, FAQ, source code archive, list archive, book reviews, dsp > links > http://music.columbia.edu/cmc/music-dsp > http://music.columbia.edu/mailman/listinfo/music-dsp > > ----- > Aucun virus trouvé dans ce message. > Analyse effectuée par AVG - www.avg.fr > Version: 2015.0.5645 / Base de données virale: 4281/9062 - Date: 05/02/2015 > -- > dupswapdrop -- the music-dsp mailing list and website: > subscription info, FAQ, source code archive, list archive, book reviews, dsp > links > http://music.columbia.edu/cmc/music-dsp > http://music.columbia.edu/mailman/listinfo/music-dsp -- dupswapdrop -- the music-dsp mailing list and website: subscription info, FAQ, source code archive, list archive, book reviews, dsp links http://music.columbia.edu/cmc/music-dsp http://music.columbia.edu/mailman/listinfo/music-dsp
