What is a E/G# chord and how do you construct them?

They're called 'slash' chords. The part before the slash indicates the basic chord, and the part after the slash indicates the note to use as the bass.

When the tone after the slash is a chord tone (as in E/G#), it's a way of specifying which inversion of the chord to use. When it's not, it's either a way to indicate a chord the author couldn't figure out (Aº/Gb = Cº7) or it's a way to show a walking bass line (E, E/F#, E/G#, A).

I'm not being facetious about authors not being able to figure out chord names - I'm frequently seeing slash chords on the internet that don't make sense in the progression... but if you look at the chord tones, the result makes sense. It's pretty clear the guitarists doing the posting have a decent ear, but they need to frame things in terms of chords they know: Dsus4/B instead of Gadd9 for a song in the key of C, for instance.

There's one special case you won't see too often, called a polychord. Those show chord names both before and after the slash - one guitarist plays each chord. Showing something like C/Bbm will result in guitarist 1 playing C-E-G, and guitarist 2 playing Bb-Db-F. The result to the listener would be a combination of the two chords (C-E-G-Bb-Db-F = C11b9). They're used to get voicings that are unplayable by one guitar, voicings that contain more than six different notes, etc.

Cheers for that.

what really annoys me is when the note after isnt in the chord, i know it shouldnt tick me off but if people are gonna write music do it right.

C/G = fine
C/B = no, because there is no B in a C chord..
CM7/B = yes good, actual chord named
C7/Bb = yep, dominant seventh, moving to F, more obvious

but just like

A/D# or whatever, doesnt make sense.

Really, with all respect, but theory is not a set of rules. If I happen to like either of the following two chords:

[x 6 7 6 5 5] and [x x 13 14 14 12]

then why not use them? Because some mysterious dude called 'theorie' says noone did it before? Why can't I use a C-C/B-Am7 progression if I feel like it? Theorie is just a collection of things others did in the past. It isn't a book of rules to be used in the future.

Another example: C D F F#. What you're going to call it? 'Csus4Add9 with a flattend fifth'? 'D9# without fifth'? 'Dadd9#/C without fifth'? Or maybe even a 'F#7M add13- with a flattened fifth'? Does it even matter? There are a billion ways theory can describe this chord but in the end it's just that important chord used in Purple Haze. Did hendrix care about it's name? Did he knew how it could be explained? Does it sound cool?

Theorie describes what you play, it doesn;t approve or disapprove.

Well since you bring it up... there aren't a billion ways to theorize that as a chord, there's one. Traditional harmony is built of major and minor thirds, and even if you use the enharmonic spelling (B#-D-F#-E# = 1-bb3-b5-11) you don't have the requisite major/minor thirds.

That doesn't mean it's outside theory, though, just that it's outside tertian harmony. Theory also encompasses secondal, quartal, and quintal harmonic systems... the intervals in C-D-E#-F# (to use a different enharmonic spelling) are all seconds, so this is in secondal harmony, and secondal chords are called tone clusters. Hendrix didn't 'invent' it... it's been used by Ravel, Berg, Ives, Bartok, Prokofiev....

As for theory not 'allowing' C-C/B-Am7 - It's a C chord (E-G-C-E on the first four strings) with a moving bass line. That's been around for hundreds of years. In the context, C/B isn't a chord at all - it's a way of including the melody note (B) with the chord (C) as a fingering instruction. Just because a guitarist might call it a chord doesn't make it so, in harmonic terms.

No one is saying it's rules.

I think Piston said it best:

"...musical theory is not a set of directions for composing music. It is rather the collected and systemized deductions gathered by observing the practice of composers over a long time, and it attempts to set forth what is or has been their common practice. It tells not how music will be written in the future, but how music has been written in the past."

Noteboat: doesn't that somewhat depend on your definition of 'chord'? being the simpleton I am I tend to stick to the english dictionaries which all tell me that a chord is 'three or more musical tones sounded simultaneously'. dutch dictionaries give the same definition in Dutch, so it is quiet safe to assume that that is the official definition of chord in the western world. Which would actually mean that a powerchord can be a chord as well, since it has only two notes but three tones.

So if we stick with the official definition of chord, a C/B is a chord without any doubt.

A powerchord doesn't have three.

It's like two points define a line. Well not if they are the same point they don't.

According to the definition above (which you might not agree with) it is about three tones, not three notes.

[0 2 2 x x x] E B E. Two notes, but the two E-notes are different tones since they are an octave apart.

[12 2 2 x x x] would not be a chord, since it has two E-notes of the same tone.

If we're going to split hairs, you can't play notes, you can only play tones. Notes are the written or verbal representations of tones, and tones exist only in sound.

According to the Harvard Brief Dictionary of Music: A chord is the simultaneous sounding of three or more tones (two simultaneous tones are considered an interval rather than a chord).

Aha, you say, that proves my point! c and c1 are different tones!

Not so fast... let's look up 'octave' in the same dictionary:

...the octave is the most perfect consonance, so perfect indeed that it gives the impression of being a mere duplication of the original tone...

As a result, we end up (in theory terms anyway) with tones that can be played in any octave and still result in the same chord - CEG is C major, as is EGc - and we throw out tones that are doubled at octaves - so CEcec1e1 is analyzed as just CE... an interval.

NoteBoat: I think if you knew any more about music your head might just explode.

Is there room in there for anything else?! :lol:

Lots of people know more than I do, undercat. There's also different ways of approaching things... for example, I've learned a trick or two about how to view dominant 7th resolutions from some of Helgi's posts - he's thought about them in ways I hadn't.

In the same way, I've noticed things over the years that I haven't heard from other people.... like the top three notes of any chord are going to form a triad (the sole exception I've found is the 6/9 chord).

I read a lot about music, and I listen a lot... and I'll come back to styles after time away and see if I can find other things I can do with them. Lately I'm learning surf music (for a gig), more new country (for a student), and doing more reading and listening on Gregorian chants (cause I think they're cool). I'm playing around in my composing with choral antiphons, so this weekend I'll probably dust off a vocal arranging book and figure out what I've forgotten or missed the last time through.

I sure hope there's room for more stuff, cause I hope to have a lot more years of learning ahead of me yet!

I guess another question might be where are you most likely to find them/ use them other than just where they sound good?

FYI, I see these types of chords quite a bit in the Catholic folk hymns we play at church. I don't know if all folk music is that way, or if it's just particular to the religious music.

For example, one prayer that is set to music, the "Gloria", uses many of these chords with altered bass notes. The chrous to it is mainly a progress on of D>A/D>G/D>D. It's all played on the bottom four strings and sounds quite nice. The song also uses D/F#, G/B, G/E, and C/G. The chnages in this song also are quite frequent, at least once each measure and many times the chord changes on each beat. It's alsmost like you are playing the melody in chords.

Many other songs in oor hymnal also use the altered bass notes.

Most of the time when a slash chord like E/G# is written in music, the guitar plays an E major chord, the bass player plays G#.

Often, such transcripts come from keyboard-based music. That's why you see them a lot in church music.

It is also commonly used to indicate a moving bass line:

E/B E/G# E/F# E usually means that while the guitar holds an E chord, the bass plays B-G#-F#-E (although nimble fingered guitarists may actually be playing both parts).