Methodology
The following description shows how I was able to achieve a repeatable .02% error in my calibrations.
- Listen for a songs underlying pulse, almost always found as quarter or eighth notes;
- Begin the recording again, and using a lap stop-watch. I use a Nike 300 lap stop-watch for this), start watch on the first discernable beat;
- Upon the next beat, start to count. I use a simple mathematical calculator set to "0 + 1=", thereupon making the first time I hit the = key beat one, and so on. *Every* underlying beat is to be counted;
- To perform actions 1-3 above, use one hand to hold the watch, the other to keep every beat counted;
- Each time the counter hits a factor of ten, press the "lap" button on the stopwatch, thereby measuring the 10 beats that have immediately been heard while keeping the total time unaffected. This is a common way to time swimming laps and track laps;
- At song's final discernable beat, hit the "Stop" button rather than the "Lap" button on the stopwatch. The final stop will also measure the final beats in isolation.
- Record all data;
- Repeat same process eight times;
- Average the entire song. Using simple cross multiplication, you can determine the song's "average tempo" or "MEANSPEED"
- Average each group of ten beats. Using simple cross multiplication, you can determine the speed albeit at an error of closer to 1 %, of each grouping of beats. One need not use 10 to create the speed graphs I have so created. So said, in my experiments groups of ten usually make for the most easily seen speed trend of any song;
- To create a speed graph yourself, simply use the obtained numbers on a spreadsheet software program (I have been using Microsoft's Excel since 1995 with most excellent results);
- If it is simply a general number within 3-5% error rather than the scientific error described above, simply use the "tap link" on this site, or any of the other such "tempo" programs available.
Simple and accurate.
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