Wednesday, December 11, 2013

Vickers's Law: There are infinitely more ways to make sounds sound worse than there are to make them sound better.

(This assumes that we define "better" as being more similar (e.g., in a least squares sense) to some desired (clean) sound.)

Friday, September 20, 2013

A new DAFX article of interest: Alex Wilson and Bruno Fazenda, "Perception & Evaluation of Audio Quality in Music Production", http://dafx13.nuim.ie/papers/04.dafx2013_submission_47.pdf . From the abstract:
A dataset of audio clips was prepared and audio quality assessed by subjective testing.... A new objective metric is proposed, describing the Gaussian nature of a signal’s amplitude distribution. Correlations between objective measurements of the music signals and the subjective perception of their quality were found. Existing metrics were adjusted to match quality perception. A number of timbral, spatial, rhythmic and amplitude measures, in addition to predictions of emotional response, were found to be related to the perception of quality. The emotional features were found to have most importance, indicating a connection between quality and a uniļ¬ed set of subjective and objective parameters.

Thursday, June 6, 2013

I just noticed an article, "'Dynamic Range' & The Loudness War" by Emmanuel Deruty, in the Sept. 2011 SOS, http://www.soundonsound.com/sos/sep11/articles/loudness.htm .

This article is very interesting - not sure what to make of it. It claims to prove that music is not getting less dynamic.

My AES paper on the topic, http://www.sfxmachine.com/docs/loudnesswar/ , found a noticeable decrease of "dynamic range" from 1985 to 2010 (from almost 13 dB to less than 8 dB), but this used the "TT Dynamic Range Meter", which actually measures something more like crest factor than dynamic range.

I agree that the term "Dynamic Range" is ill-defined and maybe not relevant here - a statistical measure would be more appropriate. It would be surprising to me if the "Loudness Range" (http://www.aes.org/e-lib/browse.cfm?elib=16254) has not decreased - I'd be curious to hear what the original creators of the Loudness Range measure would say about this.

Clearly more work is needed to figure out how musical dynamics have changed and which measures are most relevant.

Saturday, May 25, 2013

A new IEEE article quotes my loudness war paper and presents a linear and perceptually transparent method of reducing peak amplitudes by around 2.5 dB using an allpass filter chain. Clever idea.

Parker, J.; Valimaki, V., "Linear Dynamic Range Reduction of Musical Audio Using an Allpass Filter Chain," Signal Processing Letters, IEEE , vol.20, no.7, pp.669,672, July 2013.
http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6516022&sortType%3Dasc_p_Sequence%26filter%3DAND%28p_IS_Number%3A6515149%29