SKGB wrote:not necessarily true. you can definitely use 5, 7, 9, etc beats, it's just they line up less frequently (prime numbers and all that hot shit).
What's he saying is that with the exception of time sig 1/* (a rarity, only really designated in classical music-a lot of the time people just tack on this extra beat onto the previous measure), all combinations are broken down into counts of 2 and 3.
For example, group of 5 can be counted as
1 2 3 | 4 5
or
1 2 | 3 4 5
You CAN use larger numbers, yes, but it really depends on what type of grouping we're focusing on. For example, (and one of the guys might be able to correct me on this) Cheap Dinosaurs has a song in 13/8. We just call the tune right now, "Thirteen."
1 2 3 4 5 6 7 8 9 10 11 12 13
To count up to thirteen while playing along is irrational and unnecessary.
<warning science nerd post coming>
Short-term memory research suggests a span of about 7 chunks of material with a standard deviation of 2. So 7 pieces, plus or minus two. Average peak memory span can range from 5-9 chunks, arguably. Counting up to 13 means you'd have to remember your place when counting and while playing Dino's wacky lines that are just mean to guitarists, I know I can't do that myself! So we can break it down. So our maximum can be anywhere from 5-9 total chunks. It's interesting to note that chunks are not just individual points of data, but a collection of information. So instead of counting beats, we can count GROUPS.
Of course it depends on where the rhythmic accents are within the song, but one way of counting this 13 could be breaking it down into groups of 2 and 3. This is what the previous posts were referring to, IMO (correct me if I misunderstood! ) :
1 2 | 3 4 | 5 6 | 7 8 | 9 10 | 11 12 13
Now we have five groups of 2 and one group of 3. Six chunks. Half as small, but we want it as small as possible so we don't have to think about it at all. Let's try something new:
1 2 3 4 | 5 6 7 8 | 9 10 11 12 | 13
Here, I doubled the groups of two into fours. Now we have four groups total. This works because you can now just treat a group of four as a "two" that's twice as long. Like so:
1 + 2 + | 3 + 4 + | 5 + 6 + | 13
But we still have that damn extra beat 13 at the end...what do?!?! We COULD break it down into 2 and 3...
1 2 3 4 | 5 6 7 8 | 9 10 | 11 12 13
OR
1 2 3 4 | 5 6 7 8 | 9 10 11 | 12 13
But this still has four groups. Plus, there's two ways of counting that group of 5, like my very first example. So in this case, I would do what SKGB proposed and actually use a group of 5 here!
1 2 3 4 | 5 6 7 8 | 9 10 11 12 13.
Three groups. Only three chunks to remember. 4, 4, 5.
13.
disclaimer: this is COMPLETELY dependent on the music. If the rhythmic accents explicitly impose a subdivision of groups, it's probably easier to count the measures in that manner. But for tackling an unfamiliar long measure, this is the method that I like to do, at least. This is by no means an official way of doing it but just something that helps me personally!