How would I convert 6/8 dotted crotchet = 66 to a 6/8 regular crotchet value?

There's a piece I'm practicing that's in 6/8 and has written on it that a dotted crotchet is equal to 66.

I want to practice this with a metronome set to a 6/8 time signature because I want to be able to practice a hard semiquaver section while also being able to keep track of where I am in the bar.

What should I set my tempo to so that I can do that and how can I find that out in the future if I need to do it again?

P.S. Sorry if I missed any obvious solution or something, I'm really tired.

• You are eventually going to need to set your metronome to 66 bpm and play 6 notes per metronome tick. Before then, for practice, I don't care what slower tempo you set your metronome to. Apr 28 '20 at 11:18
• Hi Rowan. Welcome to Music P & T! Dekkadeci means THREE notes per tick of course. If you set it to 198 (3*66) it will click on each quaver. If it has a bell maybe that will ding on the first beat of each bar. Is that what you were asking? Obviously you can slow it down to anything while you practise. (*US practice) Apr 28 '20 at 11:47
• @OldBrixtonian - I mentioned 6 notes per tick because the OP/question specifically mentions playing semiquavers. Apr 28 '20 at 15:27
• What are you asking? Set the metronome to whatever speed you wish to practice at. Apr 28 '20 at 15:31
• @Dekkadeci Sorry. Yes - you're quite right. Apr 28 '20 at 16:16

If a dotted crotchet (corresponding to 3/8) is 66 (this means in 1 minute there 66x3/8 -> you have to multiply the 66x3x1/8 = 198. This is what you have to choose if you want to count the time based on 1/8. But it will be better you start with a slower tempo, maybe 1/8=150.

What should I set my tempo to so that I can do that and how can I find that out in the future if I need to do it again?

As you can see in this example you always have

1. to know how many notes of the unit (?/8) in the given time signature (6/8) are contained in the given tempo unit (dotted quarter=3/8)

2. than you must multiply the counter (3) of the ratio (/8) with the tempo (66) and you have the b.p.m. for your metronome.

A dotted crotchet is half a bar in 6/8. So there will be two clicks per bar to follow. Each click will represent three quavers. Or six semis. If you triple the metronome speed to 198, each click will represent two semis.

Obviously, in practising, you'll slow that a bit - maybe 160, to tidy up the whole timing.