Hello
I heard someone say the other day that if you have a piece of music..... for example in E Major 4 sharps and you change it to three flats E flat Major.. ( I think this is correct).....then it will be ok to play. As long as the changes add up to seven. Ie 4sharps plus 3 flats.....
Is this true ...if so what would be the differences...Does it work in minor keys...can you only change from major to major and minor to minor...(suppose if it's true that would be obvious)....
It's not April the 1st. but this may not be true...although music seems to be very mathematical and stranger things do happen. Does anyone else have any other mathematical oddities that are worth knowing...
BFN Mike

I'm sorry. I have absolutely no idea what you're on about.

Never worked that out before, I just do it....

Minor to minor would work in the same way as major to major as the relationship between the key signatures is the same.

The mathematical relationship I DO use is to check tricky intervals by inverting them.

What???!!! Confused too!

What do you mean "OK to play"? It will be in a different key butr otherwise OK.!

I think what you mean is that the number of sharps / flats for a scale based on a given note will always add up to seven when combined with the number of flats / sharps in a scale based on a note a semitone lower or higher.

Not easy to explain but this is what I mean.

D major -2 sharps - D flat major 5 flats

A major 3 sharps - A flat major 4 flats

Bflat major 2 flats - B major 5 sharps

etc.

Might be a useful trick in an exam some day?

yes that's right, and yes, it works in minor keys too. As long as you are playing solo of course, or everyone else does the same thing!

So you can play in Ab major for example instead of A major if you just change the key signature from 4 flats to 3 sharps. D major (2#s) becomes Db major (5 flats). F minor can be played in F# minor (if you must!!!) E minor will become Eb minor.

Bear in mind that minor keys tend to use more accidentals so will probably be a bit more complicated to read in the new key. For instance, the C# in D minor would become C natural in D flat minor, but the Bb of the key siggie would become B double flat - I think. *Brain hurts already.*

Yes, it works.

Think back to why keys exist in the first place: in a diatonic scale, the 'normal' scale, the notes in C Major would be, simply, C D E F G A B C. The important thing is the intervals between the notes: tone tone semitone tone tone tone semitone. If one started a scale on E with no accidentals, the intervals would be semitone tone tone tone semitone tone tone. The whole point of 'keys' To start the scale on 'E' one has two options to preserve the tone tone semitone tone tone tone semitone relationship.

So. one has two options from E:

1) Flatten the first, fourth and fifth notes of the scale by a semitone, making it fit the pattern again

2) Sharpen the second, third, sixth and seventh notes of the scale by a semitone, making it fit the pattern again.

It doesn't matter, per sé, which one one chooses - so one can play a piece in Eb in E if one really wants to .

We do that in chapel with things that are in for instance B major - Bb just involves thinking in two flats rather than 5 sharps, and is a semitone lower which can only be a good thing for congregational singing....! Unfortunately newer band recruits (esp guitars) will struggle with Bb so lately we can't cheat!

Yes, that works. It all comes out a semitone lower and all the relationships (which is all most people can hear) remain the same. When you are reading this music, you have to think quickly about accidentals e.g. a natural in E (usually? always? I haven't got time to be sure) turns into a flat in Eb.

Yes, the mode remains the same, because it depends only on the intervals.

There are many mathematical features of music, in both notation and acoustics.

For an obscure notational curiosity, it turns out that a part written for Horn in Eb (treble clef) can be easily read by a bass non-transposing instrument if you mentally assume the bass clef and a key signature of three flats. There is an effective octave transposition of course. The utility of this? Well, this is the very way 3 of Mozart's 4 Horn Concertos are scored (the fourth is in D rather than Eb).

So, should you want to try these super works on bassoon, trombone, or cello, it would be quite straight-forward to do so.
Just don't tell any horn players

Hello
Just to say thanks to everyone...It's abit complicated but seems like it was an interesting question...At least nobody started fighting on this thread.
BFN Mike

nobeoy fighd heere

Tell them to buy a capo.

We often put pieces in E major down to Eb so the transposing instruments (trumpet, cornet and alto sax) don't have to play in 6 or 7 sharps.

I have asked... they'll get there! The new bassist might still complain!


We no longer have any transposers, (used to have a cornet) though I think there are a couple of pieces we do that to anyway just because it's easier.

This works in reverse too. Brass band players mostly play from treble clef, transposing parts, so that they can easily move from one instrument to another (not too different in size, so as to minimise the difficulty of the embouchure change). However, Eb tuba players use the bombardon part, this being bass clef, concert pitch, remove three flats (or add three sharps) and think very quickly about accidentals or play these notes by ear.