So I'm reading about these inversion symbols and figured bass symbols in this music theory book I have and it's really confusing me. I understand how the complete figured bass symbols work but then they throw in the symbol most often used instead of the complete figure and I don't see how anyone came to these abbreviations. For example. a B-D-G chord would be completely figured as 3-6, which makes sense, but the symbol that people apparently use is just 6. Why drop the 3?

I'm also not even sure if this is important. I've never seen anyone use these figured bass symbols before. Everyone uses lead sheet symbols instead, which are a lot easier to understand. Is this even worth learning?
You just list the degrees above the root. Root is 5/3. First is 6/3. Second is 6/4. Then they just drop the notes that would be there in a root position triad, so it just becomes nothing for root and 6 for first.
If I recall correctly, the number at the bottom (say when 3 is below 5 or 5/3) correlates to the interval in degrees between the lowest note and the second lowest note. The other number correlates to the interval in degrees between the lowest note and the third lowest note (or is it the highest note?)

Say, C, E, G is a 5/3. This is because C to E is a major THIRD and C to G is a perfect FIFTH.

Because C is the lowest note, we call this a root position chord.

3-6, which makes sense, but the symbol that people apparently use is just 6. Why drop the 3?
I dunno, this doesn't make sense to me either.

Technically, a sixth chord could be in the first or second inversion. As in, E-C-G is a sixth, but so is G-E-C. Maybe it's because, if I recall correctly (once again), the fifth isn't allowed in the bass like that and so the latter is disregarded.

A lot of classical era music theory makes more sense if you know the basics of counterpoint. For instance, did you know that a lot of music won't have real chords and instead have a number of different melodies going at once which, from time to time, form chords with each other? When I realised this, it completely mindfucked me.
``````        ,
|\
[U]        | |                     [/U]
[U]        |/     .-.              [/U]
[U]       /|_     `-’       |      [/U]
[U]      //| \      |       |      [/U]
[U]     | \|_ |     |     .-|      [/U]
*-|-*    (_)     `-’
|
L.``````
Quote by demonofthenight
Technically, a sixth chord could be in the first or second inversion. As in, E-C-G is a sixth, but so is G-E-C. Maybe it's because, if I recall correctly (once again), the fifth isn't allowed in the bass like that and so the latter is disregarded.

If its just labeled 6 it will be first inversion. 6/4 is used for second inversion. They just write the degrees which are different from a basic triad over that bass note.
Quote by demonofthenight
For instance, did you know that a lot of music won't have real chords and instead have a number of different melodies going at once which, from time to time, form chords with each other? When I realised this, it completely mindfucked me.

Yeah, I realized that recently, too. It's harder to see when there are two clefs so it didn't hit me at first but I found that realization very interesting.

@isaac_bandits: So would the second inversion just be written as 6/4? The book never explained that they just dropped the notes that were in the root triad and I think that's where the confusion was.
Quote by iforgot120
@isaac_bandits: So would the second inversion just be written as 6/4? The book never explained that they just dropped the notes that were in the root triad and I think that's where the confusion was.

Yeah.

So if you're in C (using figured bass), and you have a C in the bass, 5/3 would be a C major in root position; 6/3 would be A minor in first inversion; 6/4 would be F major in second inversion. Since the fifth and third are so common, they can be left out. If you want to write them in for clarity, its not wrong, though. They're just excluded as it's more efficient.

If the numbers are are next to roman numerals, the numeral indicates the root of the chord, not the bass. So in C, I5/3 means root position C, I6/3 means first inversion C, and I6/4 means second inversion C. Again the 5 and 3 are optional.

When using accidentals, the accidental applies to that scale degree. If there's an accidental with nothing after it, it means to do that to the third (so V♮ means the V chord has its third made natural, as the raised leading tone in a minor scale [with atleast 3 flats in the key signature]). If you want to alter the fifth, then you have to include the 5 after it. i♭5/♭ means a diminished i chord, while i♭/♭ doesn't make sense.
Figured bass is a system used for continuo instruments (any instrument capable of producing harmony, normally a harpsichord and a cello doing the bassline.

The numbers indicate the intervals from the bass note that is written down.

3/5 means root position, its is normally disregarded apart from Ic - V progressions.

6/3 is first inversion, and the 3 is normally disregarded. Once you get used to reading it you wont get confused.

6/4 are second inversion triads and are always written as 6/4.

7th chord inversons get slightly trickier.

Dont get me started on 13th chords although iv never seen 13th chords figured in a piece of music.

You can also alter the chords.

A # or a b on it's own applies to the third of the chord. If you want to alter anything else you have to add it next to the interval you wish to sharpen/flat.

Quote by iforgot120

I'm also not even sure if this is important. I've never seen anyone use these figured bass symbols before. Everyone uses lead sheet symbols instead, which are a lot easier to understand. Is this even worth learning?

It's handy to know if you plan to compose music for continuo instruments or if you play a continuo instrument yourself. If your a guitarist who likes playing blues or metal however, i would say no. Although there would be no harm in learning it anyway.
Last edited by griffRG7321 at Jan 9, 2010,