Resolving enharmonic dissonances

[Composer]

Hi.


In traditional music theory, is lets say G# and Ab a dissonnanse? I would say so. If so, is there a rule for resolving it?

This is just a thaught, I had..

What do you say?

Serious comments only, please.


Regards

Composer

[Gryvix]

ofcourse there should be a difference with the comma system, but it can't be played by lots of instruments... So I don't take that in account anymore.

[Composer]

Originally Posted by Gryvix

ofcourse there should be a difference with the comma system, but it can't be played by lots of instruments... So I don't take that in account anymore.

.........what??

[reith]

Originally Posted by Gryvix

ofcourse there should be a difference with the comma system, but it can't be played by lots of instruments... So I don't take that in account anymore.

Likewise...what????

Well, it's an enharmonic - on keyboard instruments working to the tempered scale, it's the same pitch/frequency but it isn't theoretically the same and might be played differently (and yield a different pitch) on instruments other than keyboards.

It's hard to imagine A-flat and G# existing at the same point in harmony except as a passing note. I reckon in very strict terms it's a dissonace because, in traditional theory, it is a diminished second.

R

[Composer]

Originally Posted by reith

Likewise...what????

Well, it's an enharmonic - on keyboard instruments working to the tempered scale, it's the same pitch/frequency but it isn't theoretically the same and might be played differently (and yield a different pitch) on instruments other than keyboards.

It's hard to imagine A-flat and G# existing at the same point in harmony except as a passing note. I reckon in very strict terms it's a dissonace because, in traditional theory, it is a diminished second.

R

Agree

[Gryvix]

Well the principle about commas is the following:
Between eg. G and A there are 7 commas. G# should be 3 commas higher than G while Ab is 3 commas lower making Ab not equal to G#.
But it is a rule not very known nowadays...

But I prolly understood the question wrong

[Thorolf]

Originally Posted by Gryvix

Well the principle about commas is the following:
Between eg. G and A there are 7 commas. G# should be 3 commas higher than G while Ab is 3 commas lower making Ab not equal to G#.
But it is a rule not very known nowadays...

But I prolly understood the question wrong

I suggest you have got this one backwards, as the diatonic semitone (112 cent) is bigger than the equally tempered semitone (100 cent). The equally tempered whole tone interval is 200 cent. Therefore, adding a sharp to G actually makes it higher (G+112 cent) than the enharmonic A flat (A-112 cent, or G+200 cent-112 cent=G+88 cent), making G sharp 24 cents higher than A flat.

Translating this to the comma approximation, you can say that you still got 7 commas to a semi-tone (there are different kinds of commas, but let’s just use your definition for the sake of the argument ). Accidentials add (or subtract) 4, not 3 commas, and you got G sharp one comma higher than A flat.

More here: http://www.terryblackburn.us/music/t...ent/stoess.htm

and here: http://www.xs4all.nl/~huygensf/doc/measures.html



Regards

[Silhouette]

wow, you seem to be fountain of knowledge! oh and btw i'd say an enharmonic too. :wink:

[stevel]

Originally Posted by Composer

Hi.


In traditional music theory, is lets say G# and Ab a dissonnanse? I would say so. If so, is there a rule for resolving it?

This is just a thaught, I had..

What do you say?

Serious comments only, please.


Regards

Composer

Are you talking about the interval from G# up to Ab? First of all, in traditional music theory, such a combination would be unlikely. It would more likely be written as a unison. Where did you see this? Sometimes, in orchestral music the strings might play a G# and the Flute an Ab, but they are the same pitch - they are enharmonic and the editor chose that spelling bases on some other factors.

G# to Ab, if you actually had it, would be a diminished 2nd. Diminished intervals by definition are dissonant however this is not a diminished interval commonly found in diatonic systems and would only likley be encountered in a style where dissonance resolution is not a big issue.

Steve

[Composer]

Originally Posted by stevel

Are you talking about the interval from G# up to Ab? First of all, in traditional music theory, such a combination would be unlikely. It would more likely be written as a unison. Where did you see this? Sometimes, in orchestral music the strings might play a G# and the Flute an Ab, but they are the same pitch - they are enharmonic and the editor chose that spelling bases on some other factors.

G# to Ab, if you actually had it, would be a diminished 2nd. Diminished intervals by definition are dissonant however this is not a diminished interval commonly found in diatonic systems and would only likley be encountered in a style where dissonance resolution is not a big issue.

Steve

I'm just talking about the interval G# to Ab - just a thought.

But after the Theory of Overtones by Schönberg, s should be a very dissonance.