Subject: Re: Rhythm perception From: Dan Ellis <dpwe(at)EE.COLUMBIA.EDU> Date: Tue, 15 Nov 2005 09:27:35 -0500>> We were discussing rhythm patterns the other day and the question came >> up about how one determined the start of a pattern. I think this is the "downbeat detection" problem, which is distinct from the problem of deciding the main repetitive period of the rhythm i.e. the spacing between downbeats. I'm not a musicologist, but I've tried to build a system to align downbeats in different rhythm patterns, so I've thought about it a little. Here's one piece of evidence: Tristan Jehan presented a poster at the recent Mohonk WASPAA on a machine learning approach for predicting the downbeats, which he tested on a style of Brazilian music called maracatu. He played the maracatu examples to listeners familiar with northern-hemisphere western music, and they could not identify the downbeat - but of course maracatu fans have no problem indicating the appropriate downbeat. http://web.media.mit.edu/~tristan/Papers/WASPAA05_Tristan.pdf That to me is powerful evidence that downbeat is a cultural norm and not strongly based on some universal. DAn.