Re: [LAD] Listing lowest and highest frequencies in a track?
On Fri, 2012-08-31 at 20:11 +, Fons Adriaensen wrote: Human hearing easily violates the 'uncertainty principle', and it can do this by making assumptions about the signal (such as the one made above). If a 50 Hz bass note is a quarter tone (1.5 Hz) out of tune, we can easily hear this even if the bass plays more than 1.5 notes per second. If it was 50Hz and nothing else (a sine) you wouldn't notice, but when the soup is served, it comes with harmonics extending at least 10 x base frequency - and that is what you hear Ciao, ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
Re: [LAD] Listing lowest and highest frequencies in a track?
On Tue, 28 Aug 2012 12:52:24 +0100 Harry van Haaren harryhaa...@gmail.com wrote: I use Fons' JAAA for this. It has a freeze button, so when you hear a low note, you'll see it, then hit freeze, then there's peak analysers that you can place on the display, and it'll tell you its Hz (and estimate a note). dB can be read right off the Y axis. Better use japa and then use the setting where the line isn't going down (or is going down _very_ slowly). Use the accuracy as you like. But somehow I suspect the lowest frequency will be some kind of rumbling noise from either a mic stand or from some synths/effects unwanted subharmonics. You should set a minimum amplitude below you ignore a frequency as lowest frequency. If you don't do it, you are limited by 1/(2*window_length). And given that you have a) noise in every recording/audio and b) a single almost delta-peak will have all frequencies, you will also have frequencies down to the minimum detectable by fft... Have fun, Arnold signature.asc Description: PGP signature ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
Re: [LAD] Listing lowest and highest frequencies in a track?
On Mon, Aug 27, 2012 at 10:54:28PM -0600, Bearcat M. Şándor wrote: Folks, Is there a Linux program out there that i can throw a wave file at that will tell me what the lowest and highest frequencies are in it, where they are and at what dB they occur? Do you mean dBm? dB is a ratio. -- If you're not careful, the newspapers will have you hating the people who are being oppressed, and loving the people who are doing the oppressing. --- Malcolm X ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
Re: [LAD] Listing lowest and highest frequencies in a track?
On Fri, Aug 31, 2012 at 11:26 AM, Chris Bannister cbannis...@slingshot.co.nz wrote: On Mon, Aug 27, 2012 at 10:54:28PM -0600, Bearcat M. Şándor wrote: Folks, Is there a Linux program out there that i can throw a wave file at that will tell me what the lowest and highest frequencies are in it, where they are and at what dB they occur? Do you mean dBm? dB is a ratio. dbFS probably, since its digital (sample value == 0 = 0 dbFS) ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
Re: [LAD] Listing lowest and highest frequencies in a track?
You're probably even more interested in the lowest frequency component of the bass itself. If you're able to freeze JAAA at a point where the bass is playing a loud clear note and there isn't much other noise, then you should be able to see a pattern in the spectrogram. There should be a series of evenly spaced spikes or bumps. If you want to verify you've identified them correctly, if you watch JAAA in real-time, you should see these spikes bump up whenever the bass comes in. Find the frequency of the lowest spike and that is the frequency of the lowest component of the note the bass is playing. Jeremy On Tue, Aug 28, 2012 at 7:52 AM, Harry van Haaren harryhaa...@gmail.comwrote: I use Fons' JAAA for this. It has a freeze button, so when you hear a low note, you'll see it, then hit freeze, then there's peak analysers that you can place on the display, and it'll tell you its Hz (and estimate a note). dB can be read right off the Y axis. It doesn't analyse the whole song as such, but it'll get you going. Small post on DnB production / mastering, uses JAAA for visualizing the audio: http://openavproductions.blogspot.ie/2012/02/dnb-production-mastering-eq.html Cheers, -Harry On Tue, Aug 28, 2012 at 5:54 AM, Bearcat M. homethea...@feline-soul.comwrote: Folks, Is there a Linux program out there that i can throw a wave file at that will tell me what the lowest and highest frequencies are in it, where they are and at what dB they occur? I was listening to some dubstep today and wondering how low it really went. I would bet that most of the bassy music i have doesn't even go below 30 hz. Thanks, Bearcat ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
Re: [LAD] Listing lowest and highest frequencies in a track?
On Fri, Aug 31, 2012 at 6:40 PM, Paul Davis p...@linuxaudiosystems.comwrote: On Fri, Aug 31, 2012 at 11:26 AM, Chris Bannister cbannis...@slingshot.co.nz wrote: On Mon, Aug 27, 2012 at 10:54:28PM -0600, Bearcat M. Şándor wrote: Folks, Is there a Linux program out there that i can throw a wave file at that will tell me what the lowest and highest frequencies are in it, where they are and at what dB they occur? Do you mean dBm? dB is a ratio. dbFS probably, since its digital (sample value == 0 = 0 dbFS) If we really start to look at the details of this question, the dB issue is the least of concerns, but let's look at that first: Paul probably meant sample value 1.0 to be 0 dBFS. That is a clear and good definition for sample values, but powers (RMS), are not that simple: Some like to keep things a simple and just treat the signal and power levels equally, giving a full scale square wave the power of 0 dB. However, this leads to the fact that a sine wave (and thus also an isolated frequency) can have a power of -3 dB at the maximum. Some like to make things a bit more complicated, and define power dB relative to the power of a full scale sine wave. However, the biggest problem in the question is that it doesn't consider the time-frequency uncertainty, and the fundamental nature of time limited signals (a time limited signal can't be band limited). You can not measure frequencies whose period is shorter than the measurement data. That means that you can't measure the power at 1Hz with a resolution better than one second. This means that the where they are part of the question is not well defined. If you take one sample from the signal, and analyse that, you'll just have an impulse. And an impulse has equal power at frequencies from 0 to nyquist. The problem we see here will manifest itself with any time limited signal, you will have some leak which will spread all across the spectrum. This means the lowest and highest part of the question doesn't make sense: it will always be from zero (or the lowest bin) to nyquist. What you can do, is use a tool like Sonic Visualiser to look at the spectrogram of the piece (with long overlapping analysis windows). Playing around with the analysis settings should also teach you about the time-frequency uncertainty I discussed above, in a rather interactive way. It also includes nice stuff like peak frequency plotting, certainly worth a look at. -Sakari- ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
Re: [LAD] Listing lowest and highest frequencies in a track?
On Fri, Aug 31, 2012 at 09:47:56PM +0300, Sakari Bergen wrote: However, the biggest problem in the question is that it doesn't consider the time-frequency uncertainty, and the fundamental nature of time limited signals (a time limited signal can't be band limited). You can not measure frequencies whose period is shorter than the measurement data. That means that you can't measure the power at 1Hz with a resolution better than one second. This means that the where they are part of the question is not well defined. While this is 100% correct, in practice 'the soup isn't eaten as hot as it is served' (Flemish proverb, probably has equivalents in other languages). If you analyse say 200 ms of a signal then your resolution in the frequency domain is indeed limited to something like 5 Hz. So a low frequency signal such as a bass note will have its spectrum 'smeared out', but assuming there's no other signal near in frequency, the peak of the smeared out spectrum will be in the right place, and you can still discover the musical pitch. Human hearing easily violates the 'uncertainty principle', and it can do this by making assumptions about the signal (such as the one made above). If a 50 Hz bass note is a quarter tone (1.5 Hz) out of tune, we can easily hear this even if the bass plays more than 1.5 notes per second. Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow) ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
Re: [LAD] Listing lowest and highest frequencies in a track?
I use Fons' JAAA for this. It has a freeze button, so when you hear a low note, you'll see it, then hit freeze, then there's peak analysers that you can place on the display, and it'll tell you its Hz (and estimate a note). dB can be read right off the Y axis. It doesn't analyse the whole song as such, but it'll get you going. Small post on DnB production / mastering, uses JAAA for visualizing the audio: http://openavproductions.blogspot.ie/2012/02/dnb-production-mastering-eq.html Cheers, -Harry On Tue, Aug 28, 2012 at 5:54 AM, Bearcat M. homethea...@feline-soul.comwrote: Folks, Is there a Linux program out there that i can throw a wave file at that will tell me what the lowest and highest frequencies are in it, where they are and at what dB they occur? I was listening to some dubstep today and wondering how low it really went. I would bet that most of the bassy music i have doesn't even go below 30 hz. Thanks, Bearcat ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/listinfo/linux-audio-dev
