Reading time signatures
Top number, bottom number
The top number of a time signature says how many beats fill one bar. The bottom number says which note value counts as a beat: 4 means a quarter note, 8 an eighth, 2 a half.
So 4/4 is four quarter notes, 3/4 is three, and 6/8 is six eighths. That is the notation. How the bar actually feels is decided by where the accents fall.
Simple and compound metre
When each beat divides into two, the metre is simple: 2/4, 3/4, 4/4. A beat in 4/4 splits into two eighth notes.
When each beat divides into three, the metre is compound: 6/8, 9/8, 12/8. Written as six eighths, a 6/8 bar is felt as two large beats of three, so you count it as one, two rather than one through six.
The clearest comparison is 3/4 against 6/8. Both contain six eighth notes. In 3/4 they group in three pairs; in 6/8 they group in two threes. The same notes, grouped differently, produce entirely different music.
Count odd metres in groups
Trying to count 5/4 or 7/8 straight from one upwards collapses almost immediately. These metres are always felt as smaller groups.
Seven is usually 2+2+3 or 3+2+2. Five is 3+2 or 2+3. Which one a piece uses is audible in its accents, and once established it usually holds for the whole tune.
Select the signature in the metronome, put an accent on the first beat of each group, and the structure gets into your body without counting. Start away from your instrument: listen and tap the accents on your knee first, then add the parts.
What BPM refers to
By convention BPM counts quarter notes. So 120 BPM in 6/8 does not mean 120 eighth notes per minute; it means the quarter note is at 120. BeatDig follows that convention, which is why choosing 6/8 automatically shortens the click spacing to eighths.
If a score says dotted quarter = 60, that is counting the large beats of a compound metre. Those are 180 eighth notes per minute, so setting 180 BPM in 6/8 here gives you exactly that.
Read next
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How to practise with a metronome
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Click tracks for recording
A click makes editing possible, and used carelessly it drains the life out of a take.
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