Intervals Beyond the First Octave

Sometimes when I’m looking at guitar chords for songs, I see stuff like C9 chord. I looked it up and a ninth is basically a 2nd interval plus one octave.

I imagine that it goes all the way through the second octave to a 15th at the next octave. . Is this kind of knowledge useful for bass players to know? Like do people say “try playing a flat 11th” when referring to a flat third plus an octave in a minor chord?

In the major scale, I got the basic major scale shapes down but once I hit the first octave, that’s it. I get stuck. Would it be very beneficial to learn/practice/memorize the positions of scale notes over two octaves to give yourself more of a musical vocabulary when playing lines in a certain key? Anybody do this already? I really think that my next breakthrough with bass is going to come from playing more positions on the neck and being able to move around more freely.


It’s definitely worthwhile to learn the major and minor patterns for a single string in addition to the basic shapes, as a next step in learning the fretboard.

When you play up an octave using the basic shapes, you end up on the root note of the next octave. So you can just start the shape over there, with that as the root. Of course, you will run out of strings to continue the shape on, which is where the scale intervals on a single string come in handy.


Chords are most often based on triads stacked on top of one another - C major is C-E-G; C major 7 is C-E-G-B… You can continue to stack thirds on top of these and thus add the 9th, the 11th, and the 13th (that is typically where it ends).

The reason to use the 9th instead of the 2nd is that it “sounds better”. Maybe this is easiest tried on a piano/keyboard. Playing the C and the D next to it sounds “off”, but if you play the C and the D an octave up, it sounds good.

So, it is often about creating more “interesting/complex” chords without all the notes clumping together because they are from the same octave. This is also referred to as “voicings”.

By the way, the 11th is the 4th one octave up (not the 3rd as you wrote!!). You always subtract 7 :smile:

Also noteworthy: Josh had previously shown how to play “simple” major or minor chords on the bass by using the major or minor 10th instead of the 3rd (as this sounds often too muddy when played together, as a chord). Just fret the root on the E string and then the major 10th on the G string one fret over (closer to the bridge) - that’s a major “chord”. Fretting on the E string and the same fret of the G string gives you the minor “chord”.


And what if we decided to use a lower octave for one of the intervals… is that a thing in “chord notation”? Or would that change the tonic of the chord?


This is common. One very common way to play root-fifth intervals, for example, is the same fret as the root one string lower, rather than two over and one up. This is the basis of much country music in fact :slight_smile:

A fourth down gets you to the fifth in the previous octave.

This is the example Josh uses in the course:


You are probably thinking of chord inversions. A C major chord could be played as G-C-E, for example (with G the “lowest” note) - that would be the second inversion and would often be written as C/G (C over G). Still, C remains the root here…

If you do this with chords with more than 4 notes it can get pretty complicated, I guess, and then you’d certainly be able to call a chord by different names, and thus assign different “roots”. It is then often the context that decides which is the better or more appropriate “name” for this chord given the chords around it.


This is one of those things that’s much easier to visualize on a piano keyboard.


PS: bass players need to pay special attention to those inverted chords. So, if it says “C/G” in the sheet music, C might still be the root, but it is usually more appropriate for the bass to play a G here. But, again, this all has to be seen in the context of the chords before and after as well - different choices can make for different lines, more or less conventional or not and/or pleasing to the ears or not. Or, G (in this example) could be a pedal note that works for several bars with different chords on top.


Sorry to be jumping in here a bit late with my input. Everyone seems to have answered the question, but I’ll add my two cents…

As someone already pointed out, chords are built on stacked 3rds, which can be a combination of major and/or minor thirds. How you stack those thirds is what determines whether its a Major 7, Dominant 7, minor7, minor7flat5, Diminished7, etc.

If you stack additional thirds beyond the seventh, these are known as extensions. These can be 9th, 11th, or 13th, which can also be played as 2nd, 4th, and/or 6th.
A Cmaj9 for example, would be C E G B D. For the 9, you have a choice of using the D two whole steps above the 7th, or you can simply play the second tone of the scale like this: C D E G B.
A Cmaj13 would be either C E G B D F A or C D E F G A B (which is basically the entire major scale).
As bass players, we get to make choices as to which tones and what order we play in our arpeggio from the palette of tones within the given chord.

I hope my explanation is lucid enough to understand. Sometimes I know the answer, but I’m not always very good at explaining it.


If you’re wondering “why? - why use all these extended chords? Don’t they sound muddy?” - that’s a damn good question. There’s a few reasons.

  • Some kinds of advanced harmony use them while transitioning from one more basic chord to another
  • Jazz is a cult of complexity that just does this kind of thing sometimes for shiggles

but I suspect the real reason is:

  • Some of the 7 and 9 chords are much easier to play on guitar than the corresponding normal triads

(I’m mostly joking here, in case it isn’t obvious. Except the last point.)


These extended intervals are great for expanding vocabulary and ideas for playing.
Be careful though! There are some strange idiosyncrasies inside of chord notation.
One thing to watch out for:

What @PamPurrs wrote is completely logical and makes sense.
But - in most instances - would give you the wrong 11th in your chord.
In major chords, the 4th of the scale (the 11th in the chord extension - F in this example) is an avoid note (because it clashes so powerfully with the major 3rd a minor 9th below it - E in this example).
So - in most instances, whenever a major chord gets to the 11th, you’ll see it with a #11.
A maj13 chord has a #11 implied within it, so I’d make the correction to Pam’s chord spelling with this:
Cmaj13: C E G B D F# A

The sharp 11 is a big big big sound in jazz music, and it’s helpful to be aware of.
There are plenty of examples of natural 11s in major chords, but in my experience, they are much more rare.

In the minor world, the 11 is natural, because it doesn’t clash with the b3.

This is getting real deep and fairly complex.
I just wanted to wade into the chord-extension discussion here to say that:
1.) YES! Knowing these extensions and how they relate to both scale construction and chord construction is amazing and wonderful for your bass line vocabulary.
2.) It can be a bit complicated when you get into upper extensions. Lots of options, and some less-obvious assumptions around that difficult scale degree 11.


Thank you @Gio for your always brilliant and insightful explanation.


Very good and juicy thread! Thank you all for your inputs

That’s a mystery finally solved for me!


if you don’t mind spending the dosh, i am working my way through chord tones course right now and it is very good and explains all this fully. a lot of people (me included) think that the most important thing for bass players to learn, even before scales, is chord tones.


Of all the courses I’ve taken there, I would say that the Chord Tones course has been the most beneficial for me.


Now I am curious. How can you meaningfully learn chord tones (made up of notes in the scale) without understanding scales first?


i’m pretty sure that mark advocates this and i know that the guy from the excellent is really adamant about it. his view, which makes sense to me, is that bass is basically (incorrectly) taught by a lot of teachers the same as piano in which scales are much more a fundamental part of what a piano does. but a bass player’s main job is fundamentally different from an instrument like piano or guitar, our main job is to outline the sounds of a chord, not to play a chord like a piano or guitar. so he advocates learning your intervals and, perhaps more importantly, the sound of the intervals first before going on to learn scale theory. it’s almost like teaching a young kid to read, learning the building blocks first and then going on to sentences. it also relates directly to scale construction, as you start to string more and more intervals together you eventually wind up with a scale and understand that a scale is just a composition of intervals.


Thanks! That makes sense. I was confused because I read it literally and it sounded like they were recommending to learn chords before the scales the chords exist in, which didn’t make sense to me, since you need to know the notes in the chord and (to a lesser extent) the surrounding notes in the scale to be able to understand what the chord is.


You are correct @howard. If I had taken Mark’s Chord Tones course prior to the Scales course, I would have been confused. It’s doable, but it’s best to have a handle on ALL the different types of scales and modes first, and in particular understanding intervals etc.

1 Like

Like @PamPurrs, I am taking Mark’s Scales course first, then will go on to do the Chord Tones course.
From what @itsratso is saying, it sounds like Mark, being a great Bass teacher, possibly the 2nd best on the net, next to our @JoshFossgreen, it teaching both courses in a way that you can get thru either first. All of what @itsratso said is very very very similar if not identical to what I have been learning in the scales corse.
So, to elaborate on the building block analogy, I think that Mark must be constructing a tree, and on one side is full of scale leaf, and the other side is filled up with chord tone leaf.
So he is teaching the tree in both courses, but staying on one side of the tree.

They are all related in music theory, and all important to learn, and while I would not discount chord tones, I would not think I(and this is just me, going by how I learn and retain and use information)
I would be complete if only learning cord tones.

I do plan to take both and am excited to get to the chord tones eventually, but I am mastering scales and more importantly to me at this very time, intervals

I am glad to see that my interval knowledge will carry over to the chord tones once I get there.

There are many paths to get you there, sounds like we are all enjoying the ones we are on now, and that is what is best.

1 Like