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FLAC 1.4.0 released – added support for 32-bit audio

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Re: FLAC 1.4.0 released – added support for 32-bit audio

#71

I personally can't care less about 32-bit, but unfortunately a few digital music stores I buy from use this format (delivered in WAV). And I don't want to downscale them simply for archival reasons. Now I can at least re-compress them losslessly in FLAC. (previously I have to use Wavpack, which isn't bad but I'd prefer to have a single format in my media library.)

ffmpeg can downsample audio to a more manageable rate. I use it to reduce hi-res flacs to 16-48, which cuts it down to a ~third of its original size and is supported in my car stereo and everywhere else. Can't tell any difference on playback.

Audiophiles usually recommend using some better algorithms such as SSRC resampler (foobar2000 have it as plugin handily) than whatever FFMPEG provides.

I can't say I personally can tell the difference, but based on my (limited) knowledge of DSP, artifact-free resampling definitely isn't a straightforward thing.

Re: FLAC 1.4.0 released – added support for 32-bit audio

#72

Earlier quoted context omitted.

You're correct; lossless formats aren't needed by the average consumer. But the problem they solve is a very real thing. Think of the difference between a repeatedly edited JPG vs. a repeatedly edited PNG. Every save of the JPG destroys information irretrievably, whereas every save of the PNG keeps it all. It's the same with MP3 vs. FLAC: MP3 throws away information each export, but FLAC doesn't. For an example, musi…

(I think) They're not saying FLAC is pointless, just that 32 bit audio is. Even music producers record and export at 24bit, 32/64bit is only used for the effects and mixing (because compounding quantization noise and rounding errors is very real). You can't find 32 bit PCM music anywhere, even hifi DVD audio is 24bit/96khz.

> You can't find 32 bit PCM music anywhere

Yes you can (not that I think it’s useful): https://ototoy.jp/find/?q=32bit

(via https://news.ycombinator.com/item?id=32843619)

Re: FLAC 1.4.0 released – added support for 32-bit audio

#73

Earlier quoted context omitted.

ffmpeg can downsample audio to a more manageable rate. I use it to reduce hi-res flacs to 16-48, which cuts it down to a ~third of its original size and is supported in my car stereo and everywhere else. Can't tell any difference on playback.

Audiophiles usually recommend using some better algorithms such as SSRC resampler (foobar2000 have it as plugin handily) than whatever FFMPEG provides. I can't say I personally can tell the difference, but based on my (limited) knowledge of DSP, artifact-free resampling definitely isn't a straightforward thing.

> artifact-free resampling definitely isn't a straightforward thing.

It's more that in practice artifact free resampling isn't a thing at all, so you have to choose what your artifacts do.

Re: FLAC 1.4.0 released – added support for 32-bit audio

#74
post #4

Earlier quoted context omitted.

Nyquist Shannon theorem, sure. There are situations where you'd use 32bit audio but not for mastered music you'd listen to at home really. Although people still won't believe you, hence the market for thousand dollar cables and other snake oil.

From my understanding, doesn't Nyquist-Shannon assume you take infinite steps to refine the discrete steps into the final waveform? Since real-world DACs don't have infinite taps, either increasing the number of samples per second in the original audio or the number of steps done by the filter will improve how close it gets to the original waveform. Would that apply to the number of bits used to represent the level a…

[deleted]

Re: FLAC 1.4.0 released – added support for 32-bit audio

#75
post #13

Earlier quoted context omitted.

What data are you compressing?

I've used it to record oscilloscope captures. Especially useful since audio cards are cheap high res adc's.

Now that 24b/192kHz cards are widely available, I wonder if you could hook a loopstick antenna up to one and get WWVB (60kHz carrier)? In theory as long as the signal is above -144dB you should be able to tease it out...

Re: FLAC 1.4.0 released – added support for 32-bit audio

#76
post #13

Earlier quoted context omitted.

I've used it to record oscilloscope captures. Especially useful since audio cards are cheap high res adc's.

I'm amazed that consumer-grade audio cards are still available and cheap, to be honest. I can't recall having seen one in years, then again, I haven't had a reason to look for them in years either.

Anything with a mic input will work. Audio interfaces over USB are plentiful these days though the discrete PC sound card is pretty rare :(

Re: FLAC 1.4.0 released – added support for 32-bit audio

#77

Earlier quoted context omitted.

(I think) They're not saying FLAC is pointless, just that 32 bit audio is. Even music producers record and export at 24bit, 32/64bit is only used for the effects and mixing (because compounding quantization noise and rounding errors is very real). You can't find 32 bit PCM music anywhere, even hifi DVD audio is 24bit/96khz.

> You can't find 32 bit PCM music anywhere The real reason is that there's no 32-bit floating point digital audio converters, so distributing the audio in a format which needs to be quantized to be played anyway has no purpose (outside of deceptive marketing, of course). Even integer 32 bit makes no sense for a final format - the available noise floor is just beyond reasonable, 24 bit is more than enough. In practice…

I have a lynx hilo and it does 32 bit input. It’s incredibly nice for recording because if the input hits clipping range you can just lower the volume on the 32 bit recording after the fact and the recording is preserved. Lots of high end DACs have a 32 bit input output option because of this.

Re: FLAC 1.4.0 released – added support for 32-bit audio

#78
post #5

Earlier quoted context omitted.

I am a recording engineer and I will choose 32 bits over 24 any day when recording. Of course you need the right (exceptionally good!) preamps to even make a difference here, but when you are manipulating audio 32 bits and upwards (for summing) are the default (for a reason). Having something to store those files with a little bit of lossless compression is a welcome addition

> I will choose 32 bits over 24 any day why?

Because if the recording goes past the clipping range for digital audio it still records the data and preserves it. 32bit recording has serious advantages because it’s much easier to record a hot input because digital clipping is not possible. You just need to pull the volume down on the recorded clip after the fact and there is no clipping.

Re: FLAC 1.4.0 released – added support for 32-bit audio

#79
post #13

Earlier quoted context omitted.

I've used it to record oscilloscope captures. Especially useful since audio cards are cheap high res adc's.

I'm amazed that consumer-grade audio cards are still available and cheap, to be honest. I can't recall having seen one in years, then again, I haven't had a reason to look for them in years either.

To be clear: actual "PCI-slot"-ish audio cards are now rare. But USB / Thunderbolt (and previously Firewire) external interfaces are a dime a dozen. Serious audio mostly uses them now.

Re: FLAC 1.4.0 released – added support for 32-bit audio

#80
post #48

Earlier quoted context omitted.

People will use microphones to record audio like gunshots and explosions for use as sound effects. The humble snare drum will produce loads of dBs too, and is usually close-miked. You then take the same microphone and use it to record something much quieter. You end up with microphones that definitely do reasonably claim >125 dB range. The TLM102 claims something like 130 dB. How much you care about distortion will d…

>The TLM102 claims something like 130 dB. How much you care about distortion will depend on the situation. Neumann makes no such claims. They do claim max spl of 144 dB. But the TLM and is 10 dB less and this is prior to ADC of variable ability. Distortion isn't a ceteris paribus value for signal to noise calculations.

https://en-de.neumann.com/tlm-102

> Due to its enormous dynamic range of 132 dB [...]

Not really interested in dissecting what this means, or how to reconcile it with the SNR numbers. Just saying that Neumann does, in fact, make this claim.

Not sure what point you're making about distortion.

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