A sus 2 chord is when the 2nd is suspended in place of the third. (1 2 5) Csus2 = C D G
An add9 chord adds a ninth to the triad. (1 3 5 9) Cadd9 = C E G D

So basically in a sus2 there's no third, in an add9 there is
Si
Last edited by 20Tigers at Nov 26, 2009,
Quote by 20Tigers
A sus 2 chord is when the 2nd is suspended in place of the third. (1 2 5) Csus2 = C D G
An add9 chord adds a ninth to the triad. (1 3 5 9) Cadd9 = C E G D

So basically in a sus2 there's no third, in an add9 there is

ah i see

but then what if you had a chord that was 1 2 3 5?
is there like an add2 as well?
Its still add9. Whether the voicing is closed (as in within one octave) or open (greater than an octave) doesn't matter. It's pretty much all about whether there's a third or not as to whether the chord is named sus2 or add9.

C D E G is still Cadd9
Si
Quote by 20Tigers
Its still add9. Whether the voicing is closed (as in within one octave) or open (greater than an octave) doesn't matter. It's pretty much all about whether there's a third or not as to whether the chord is named sus2 or add9.

C D E G is still Cadd9

+1.
Sus comes from the word suspension and comes from the counterpoint tradition. It refers to the resolution of a single voice being delayed. Add 9 comes about because if you build a chord in thirds the second scale degree occurs as a 9th. You could have a chord with a 2nd in it but not a third that could be an add9 depending on how that note functions. If it resolves to a third it is a suspension. If it is just a color tone it is probably and add9.
Quote by MusicThinker
You could have a chord with a 2nd in it but not a third that could be an add9 depending on how that note functions.
But either way the most common way to refer to the chord would be by calling it a sus2 chord - whether it resolves or not.

Of course the use of the word suspension in the traditional sense is an interesting topic and is one of many techniques that are interesting and beneficial to learn and play with. But pretty much if it has a third you call it an add9 if there's no third call it a sus2. That's how the terms are typically used by the general population today.
Si
I think the general population today doesn't even talk about chords. The commonality of the names depends on who you talk to. Just tryin to spread some knowledge and keep things real.
Quote by MusicThinker
I think the general population today doesn't even talk about chords.

care to explain?

..imo its all about chords!
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