Re: [music-dsp] R: Sallen Key with sin only coefficient computation
Time to stop this tragedy, let's also measure frequency in dnoces On 24 Dec 2014, at 3:40 , Nigel Redmon earle...@earlevel.com wrote: On Dec 23, 2014, at 4:45 AM, r...@audioimagination.com wrote: in units of mhos (reciprocal of ohms)? Tragically, the formal name for the mho is Siemens, in keeping with naming units after the principal scientists involved. (Also, it follows from the Siemens mercury unit.) The tragedy is not only in having such a clever and descriptive term replaced by a non-descriptive one, but also the problem with the trailing s on the latter. 10 mhos = 10 Siemens; 1 mho = 1, er, Siemens... -- 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
[music-dsp] R: R: Sallen Key with sin only coefficient computation
Agreed. And also, let's measure lengths in inches/yards/miles.ehhm...ooops! :))) -Messaggio originale- Da: music-dsp-boun...@music.columbia.edu [mailto:music-dsp- boun...@music.columbia.edu] Per conto di Stefan Stenzel Inviato: mercoledì 24 dicembre 2014 09:51 A: A discussion list for music-related DSP Oggetto: Re: [music-dsp] R: Sallen Key with sin only coefficient computation Time to stop this tragedy, let's also measure frequency in dnoces On 24 Dec 2014, at 3:40 , Nigel Redmon earle...@earlevel.com wrote: On Dec 23, 2014, at 4:45 AM, r...@audioimagination.com wrote: in units of mhos (reciprocal of ohms)? Tragically, the formal name for the mho is Siemens, in keeping with naming units after the principal scientists involved. (Also, it follows from the Siemens mercury unit.) The tragedy is not only in having such a clever and descriptive term replaced by a non-descriptive one, but also the problem with the trailing s on the latter. 10 mhos = 10 Siemens; 1 mho = 1, er, Siemens... -- 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
Re: [music-dsp] R: Sallen Key with sin only coefficient computation
Naw, mhos is a one-off. It's fun, pronounceable, and in common use (since 1883!). Don't get carried away. Besides, it makes me think of The Three Stooges, and smile. Siemens makes me think of...er, um—oh yeah—a German multinational corporation headquartered in Berlin and Munich. ;-) Sent from my iPhone On Dec 24, 2014, at 3:51 PM, Stefan Stenzel stefan.sten...@waldorfmusic.de wrote: Time to stop this tragedy, let's also measure frequency in dnoces On 24 Dec 2014, at 3:40 , Nigel Redmon earle...@earlevel.com wrote: On Dec 23, 2014, at 4:45 AM, r...@audioimagination.com wrote: in units of mhos (reciprocal of ohms)? Tragically, the formal name for the mho is Siemens, in keeping with naming units after the principal scientists involved. (Also, it follows from the Siemens mercury unit.) The tragedy is not only in having such a clever and descriptive term replaced by a non-descriptive one, but also the problem with the trailing s on the latter. 10 mhos = 10 Siemens; 1 mho = 1, er, Siemens... -- 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
[music-dsp] New podcast: OSKAR HANSEN. Open Form, Open Music. Feat. an interview with David Crowley
*New podcast: OSKAR HANSEN. Open Form, Open Music* David Crowley looks at Oskar Hansen's links to the twentieth-century Polish electroacoustic scene, and the role of the experimental radio studio in Warsaw in the sixties. Link: http://rwm.macba.cat/en/specials/oskar-hansen-david-crowley/capsula In spite of having more or less remained in the shadows of twentieth-century European art history, Oskar Hansen is one of those figures who stand out as being ahead of their time. His career as an architect, a catalyst for ideas, a designer, artist and teacher can be seen as a collection of small gestures in favour of new conceptions of art and of everyday life, which seek to recalibrate the scale and the rules of the game, both in regard to the work and to the person who experiences it. In this interview, David Crowley, expert in the history of art and design in Eastern Europe during the communist era, explains the key points of Hansen's ideas and traces its connections to mid-twentieth century Polish electroacoustic music: from his involvement in redesigning the experimental radio studio in Warsaw, to his ideas for pavilions and sculptural/architectural designs in which sound is an integral part of the overall project and experience. Enjoy! -- 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
Re: [music-dsp] R: Sallen Key with sin only coefficient computation
On 24/12/2014, Nigel Redmon earle...@earlevel.com wrote: Naw, mhos is a one-off. It's fun, pronounceable, and in common use (since 1883!). Don't get carried away. Besides, it makes me think of The Three Stooges, and smile. Which in turn makes me wonder what would be measured in curlhis or lharris? -- 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
[music-dsp] Marie Curie ESRs in Sparse Methods for Audio Source Separation and Automatic Music Transcription
Dear List, Please forward to anyone who may be interested. Apologies for cross-posting. Best wishes, Mark Plumbley Marie Curie Early Stage Researchers in Sparse Methods for Audio Source Separation and Automatic Music Transcription University of Surrey, UK Closing Date: Sunday 25 January 2015 Applications are invited to a number of Marie Curie Early Stage Researcher (ESR) positions as part of the new EU-funded Marie Curie Initial Training Network (ITN) SpaRTaN: Sparse Representations and Compressed Sensing Training Network. The SpaRTaN ITN (http://spartan-itn.eu/) will bring together leading academic and industry groups to train a new generation of interdisciplinary researchers in sparse representations and compressed sensing, with applications in areas such as hyperspectral imaging, audio signal processing and video analytics. Early Stage Researcher (ESR) positions allow the researcher to work towards a PhD, for a duration of 36 months. ESRs should be within four years of the diploma granting them access to doctorate studies at the time of recruitment, and must not have spent more than 12 months in the host country in the 3 years prior to starting. At the University Surrey, we are recruiting for two Marie Curie ESRs: one in Sparse Time-Frequency Methods for Audio Source Separation, and one in Automatic Music Transcription using Structured Sparse Dictionary Learning. Marie Curie ESRs are paid a competitive salary which is adjusted for their host country. For ESRs at the University of Surrey, the ESR salary including mobility allowance is equivalent to a gross salary of approximately GBP 36,087, or GBP 38,836 for ESRs with a family. More information at the links below: ESR Post 1: Marie Curie Early Stage Researcher in Sparse Time-Frequency Methods for Audio Source Separation (https://jobs.surrey.ac.uk/084014) ESR Post 2: Marie Curie Early Stage Researcher in Automatic Music Transcription using Structured Sparse Dictionary Learning (https://jobs.surrey.ac.uk/084314) Informal enquires on these two posts are welcome and should be made to Dr Wenwu Wang (w.w...@surrey.ac.uk) or Prof Mark Plumbley (m.plumb...@surrey.ac.uk). More on the SpaRTaN ITN at http://spartan-itn.eu/ There are also other ESR posts being recruited across SpaRTaN, each with its own application process and closing date in early 2015. The full list of Early Stage Researcher (ESR) Positions (recruiting early 2015) is as follows: * ESR1 : Sparse Time-Frequency methods for Audio Source Separation - CVSSP, University of Surrey, United Kingdom * ESR2 : Automatic Music Transcription using Structured Sparse Dictionary Learning - CVSSP, University of Surrey, United Kingdom * ESR3 : Sparse Representations and Compressed Sensing - University of Edinburgh, United Kingdom * ESR4 : Task Based Dictionary Learning for Audio-Visual Tagging - LTS2, EPFL,Switzerland * ESR5 : 1-bit Compressive Imaging - LTS2, EPFL,Switzerland * ESR6 : Analysis Dictionary Learning Beyond Gaussian Denoising - Instituto de Telecomunicações, Portugal * ESR7 : Compressed Sensing for Hyperspectral Imaging - Instituto de Telecomunicações, Portugal * ESR8 : Large-scale signal processing - INRIA, France For further details, see http://spartan-itn.eu/#1 The following experienced Researcher (ER) positions will be recruiting later in 2015: * ER1 : Video Analytics for Large Camera Networks - VisioSafe, Switzerland * ER2 : Image and Video Restoration with Adaptive Transforms - Noiseless Imaging, Finland For more details of all ESR positions and future ER positions, and information on how to apply, see http://spartan-itn.eu/#1 -- Prof Mark D Plumbley Professor of Signal Processing Centre for Vision, Speech and Signal Processing (CVSSP) University of Surrey Guildford, Surrey, GU2 7XH, UK Email: m.plumb...@surrey.ac.uk -- 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
Re: [music-dsp] R: Sallen Key with sin only coefficient computation
On 12/24/14 4:32 AM, Nigel Redmon wrote: Naw, mhos is a one-off. It's fun, pronounceable, and in common use (since 1883!). Don't get carried away. Besides, it makes me think of The Three Stooges, and smile. Siemens makes me think of...er, um—oh Q: so what's long and hard and full of Siemen? yeah—a German multinational corporation headquartered in Berlin and Munich. ;-) -- r b-j r...@audioimagination.com Imagination is more important than knowledge. A: a submarine. -- 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
Re: [music-dsp] Sallen Key with sin only coefficient computation
On 12/23/14 11:36 PM, Andrew Simper wrote: On 24 December 2014 at 08:55, robert bristow-johnson r...@audioimagination.com wrote: the OTAs are there for voltage-controlled gain or, really, a voltage-controlled resistor to change the tuning of the VCF. from the datasheet They are an idealised voltage controlled current source, it looks neater to use an OTA symbol for them. for the anal-retentive, it looks like a non-trivial resistance is hidden from view. http://users.ece.gatech.edu/~lanterma/sdiy/datasheets/ota/lm13600.pdf the LM13600 looks like the transconductance, g_m is g_m = ( 20/volt ) * I_ABC okay, i get that. and it is this transconductance that algebraically goes with the capacitance to get a time constant and a filter spec. that's was my original problem, because it's not an obvious property since the resistor that *must* go with the cap is hidden inside the OTA and, in the olden daze, i only messed around with op-amps or transistor circuits. Yes the g term is your 1/R of your resistor, you can set c1, c2 to whatever you want then set the g term to get where you want in frequency, they form your RC 1 pole low pass filters, which should be clear from a glance at the diagram. when i glance at it, i see no R for the RC. none at all. It is the way that you can mix the inputs into a Sallen Key filter that is new. they're more like gates or switches (and nicely modeled as gains) and a couple of summers. also, again it show's my creaky old age, but this is not what we used to call a Sallen-Key circuit (thems were much simpler). but it, with all of this voltage-controlled resistor stuff, can take up a similar form for a SK, at least for the LPF. They aren't switches, you can mix them at any level you want, as shown later in the paper to form shelves etc. listen, when it's a single input and multiple outputs, we don't call it a multiplexer, we call it a demultiplexer. a mixer has multiple inputs and (for mono) a single output. i know that m0, m1, m2 can be any values we want in the analysis, but they're gates or switches. that's what they're being used for. Anyway, please forget about it diagram if it confuses you. legit circuit diagrams ain't confusing. signal flow diagrams ain't confusing. mixed metaphors can be confusing. wires are sorta physical things that you can do Kirchoff's laws on, signal paths are more like information pipes in which numbers flow. when i see a line go into a capacitor, i think it's a wire. when i see a line go into an adder or a gain block, i think it's a signal path. There isn't much point putting in a bunch of matched resistors, it just makes the diagram messier. Idealised components are all that is needed and they are unambiguous. Re-draw the diagram yourself if you prefer, but this was the most succinct way to express the idea. well, as Marco pointed out to me, it might be useful to include a note that all the adders and gain blocks have infinite input impedance and zero output impedance. and it might be useful to explicitly show the output current of the OTA to be g times the diff-amp input voltage. in the BPF case, you might also want to compensate Q because the bandwidth will get squished as w0 gets close to Nyquist. maybe not, whether it's LPF or HPF or BPF, the bilinear transform maps the peak heights exactly (just maps the peaks to slightly different frequencies). you might want to preserve the peak height instead and then you don't want to pre-warp Q when the resonant frequency gets high. Look later on in the paper at the Bell section. what page is that? haven't found anything that appears so titled. and i am not reverse engineering code, and other than plots, i don't see much else in the paper. haven't seen anything regarding compensation of effects of bilinear transform. 2nd-order is 2nd-order. 2nd-order IIR filters, whether they be DF1 or DF2 or transposed DF1 or DF2 or Lattice or Normalized Lattice or Hal's SVF or Rader-Gold or whatever form might pop out of your simulation of whatever analog filter, there are, when you boil it down, exactly 5 independent coefficients and 5 degrees of freedom. this is why, 2 decades ago, i made this observation regarding bell parametric eq: http://www.aes.org/e-lib/browse.cfm?elib=6326 of course, one degree of freedom: the gain at Nyquist, need not be fixed to 0 dB, which Orfanidis made use of and which Knud Christensen has generalized for the 2nd-order IIR filter. so, because of that, i recognize that they ain't *all* equivalent. but most are. point is, if you're modeling your analog bell filter (which has gain out at infinity of 0 dB) using trapezoidal rule for the integration (which is the same as bilinear transform, so the analog frequency of infinity gets mapped to Nyquist) done by the two caps, it *is* one of those that is equivalent in the sense of that Equivalence paper. the coefficient calculation is a done deal. it's
