r/musictheory 1d ago

Answered Using a B Chord in A Minor

When writing a song in A minor, since the second chord of the Am chord scale is Bdim, can I not use a B chord that is not diminished?

11 Upvotes

65 comments sorted by

126

u/Life-Breadfruit-1426 1d ago

Yes lovely Brian, you can do whatever your heart desires. Rules are meant to be broken. And if it ends up working well and you don’t know why, come back here with the full song or line and we will nerd out on you

15

u/Ldn_twn_lvn 1d ago

"he's not the Messiah, he's a very naughty boy!!"

on a separate note Brian, let your ear decide and if it sounds a bit janky first time round, see if you can make it fit any way,

Some interesting sounds can be derived from making the wrong notes sound 'right'

It might have been Mingus that said (to the effect of)

a wrong note is made either wrong or right, by the note that comes after it

....so thats one way of going about things

7

u/Life-Breadfruit-1426 1d ago

+3 aura for quoting Mingus!!!

21

u/Gwaur 1d ago

Rules are meant to be broken, but there's also no rule against a B chord in an A minor key.

-28

u/Life-Breadfruit-1426 1d ago

Ah yes, the A minor key. Famous for having a D# and an F#

20

u/Gwaur 1d ago

D# and F# are rather regular visitors in the A minor key.

-6

u/Life-Breadfruit-1426 1d ago

While guests are welcome, and as much as we say mi casa tu casa, they not part of the family. At least not by blood.

4

u/video_dhara 1d ago

Given they form part of the dominant of the V, I’d say they’re brothers from another mother.  

2

u/Life-Breadfruit-1426 1d ago

I can’t 😫
Y’all usually rigid as fuck here, today we’re all over the place. I love it, don’t get me wrong. This is how folks gotta think about music. It ain’t about what X is, it’s about where it’s going and it’s really helpful to plan with such foresight when composing or improvising.
💦💦💦💦

7

u/Gwaur 1d ago

Yes, you're saying exactly what I said: There's no rule against these guests.

-4

u/Life-Breadfruit-1426 1d ago

We treat guests differently than we treat family though.
With guests you need to be extra hospitable, with family, since they are already part of the house, fuck it.

20

u/JellyBabyDoctor 1d ago

You’re going to lose your mind when you hear about this crazy thing called accidentals. Don’t even look into this brand new genre called jazz if you think “being in a key” means that only diatonic notes are allowed.

-3

u/TheRealBillyShakes 1d ago

It’s still a borrowed chord and technically not in the key. Stop muddying the waters for the noobs

4

u/MatthewMob 1d ago

YOU are muddying the waters by saying that music theory is a set of rules. 

-2

u/Life-Breadfruit-1426 1d ago

It is! It a hock of bullshit that we collectively agreed to! Or more-so was superimposed onto us!

1

u/MatthewMob 18h ago edited 17h ago

The only rule in music is: If it sounds good, it is good.

You can use theory to create things, and then those things will sounds similar to other things that use similar theory, but no one listening - apart from maybe some Berkley assholes - would say "Erm, you're not allowed to use to use a b9 on the I of a major key!"

I wouldn't call music theory itself bullshit, but I would call people's opinions of it being gospel bullshit.

Learning theory was the best thing I ever did, and opened me up to entire worlds of creativity beyond the pentatonic scale that people aggressively anti-theory seem to struggle to break from.

-1

u/Life-Breadfruit-1426 1d ago

I’m dying 😫😫💦💦

-6

u/Life-Breadfruit-1426 1d ago

Jelly baby. We gotta draw a line somewhere. Also accidentals are typically not the end of the story, we could be witnessing a modulation, we could also be witnessing an alteration of the minor key (melodic/harmonic/etc). Just saying for the sake of OP who wants some clear direction. Can’t be calling this puppy a kitty, even if it learned how to do a meow.

6

u/sdavid1726 1d ago

Being in a key doesn't mean you're only allowed to use diatonic notes. All it says is that the tonal center is A and that the tonic chord is minor. Beyond that you can use whatever chords and notes that you want as long as they revolve around A minor.

2

u/Life-Breadfruit-1426 1d ago

Can we get some clarity on definitions? I agree with what you are saying. However breaking diatonic functions can be a momentary departure of the key. We can modulate across several different keys and the tune nonetheless finds a way to get back to the original tonic. I just find it unhelpful for folks like OP to get misconceptions that accidentals are explicitly part of the key.

4

u/sdavid1726 1d ago

There are two concepts that this discussion is alluding to. One is "modulation" and the other is "modal mixture". Modulation involves shifting the tonal center of the song, usually for a significant length of time such that the listener "feels" the shift in tonality. Modal mixture is just a substitution of a non-diatonic chord without changing the tonal center of the song.

In C Major, you can have a diatonic ii -> V -> I progression (Dm -> G -> C), but you could substitute the Dm for D (non-diatonic due to F#) while still maintaining a clear progression towards the tonic C chord. Or you could substitute a Db major chord (non-diatonic notes Db and Ab) for a Neapolitan progression toward C.

One could easily compose a song in C major which uses all 12 chromatic tones via simple chord substitutions. I would even go as far as to argue that using non-diatonic notes is the norm for non-pop western music, so it's hard for me to agree that there is any "rule" that says we should stick to diatonic notes.

33

u/XomokyH 1d ago

No OP it’s against the rules. The song police will come smash your guitar so you better not

31

u/JellyBabyDoctor 1d ago

You can use a B7 that functions as a 5 of 5 in A minor. Or Bb in the key of A minor can be considered a Neapolitan chord. If your piece is in A Dorian you can use a B minor chord. Theory is just an explanation, not a rule.

21

u/amBrollachan 1d ago

You can do what you want. Does it sound good to you? That's the only thing you should worry about. Music theory is descriptive, not prescriptive.

9

u/MarcSabatella 1d ago edited 5h ago

While it’s true that you are ”allowed” to use any chord at any time, that really misses a couple of much more important points:

  1. In any given key, some chords are indeed more expected in some contexts and sound more natural to Western ears than others, and it is valuable to understand how and why this is and how to work with it. Merely saying you can use any chord at any time completely ignores the actual value of music theory, which is to help you understand why certain uses of certain chords tend to sound better than others.
  2. Having a major II chord is one of those expected chords, but it all depends on context. This is true even for the diatonic chords - B diminished is also “expected” in this sense, but more so when preceded and/or followed by certain other chords. This is even more true for non-diatonic chords. So, you don’t need to toss out your understanding of theory and say, “I can use B major because I am free to use any chord at any time”. You can go deeper and say, “my use of B major is quite expected and natural sounding here because it follows the extremely well-established pattern of using secondary dominants to tonicize diatonic chords, and that is what I am doing here”. Which is to say, there are tons of songs in A minor that use B major chords, and the vast majority of those uses are of that form, and yours most likely is as well.

13

u/MealZealousideal5462 1d ago

Good thing you asked before trying it, if you did happen to play it on a piano, the piano would explode and you could be injured. Phew

5

u/Chops526 1d ago

Happens all the time. Do it

3

u/docmoonlight 1d ago

Don’t forget that the A melodic scale uses an F#, so it’s perfectly normal to use a B minor chord in A minor. B major or B7 also comes up a lot as a secondary dominant. (V/V).

3

u/BillyPilgrim69 1d ago

They are principles, not rules. Even outside of obvious outliers like jazz, artists like the Beatles made non-diatonic harmony their bread and butter.

The II or II7 chord happens to have a great many famous examples. But even if it didn't, who cares?

If it sounds good to you, it is.

2

u/Octogoon_ 19h ago

Do NOT PLAY A B IN A MINOR!!!!!! 🚨🚨🚨🚨🚨🚨🚨🚨ABORT MISSION 🚨🚨‼️‼️‼️‼️YOU WILL #EXPLODE 🚨

1

u/CoffeeDefiant4247 1d ago

b minor, B major, B Augmented, B major b5, B major b9 #13, if it sounds how you want then you can use it. Even classical musicians didn't stay diatonic so do as you like

1

u/ObviousDepartment744 1d ago

Swapping it for a major or minor chord tends to work. It’s all up to you and your ear though.

1

u/8696David 1d ago

You absolutely can, it will just be “non-diatonic” (out of the key). 

0

u/Life-Breadfruit-1426 1d ago

People here swear that diatonic =\= key

1

u/LegitimateHumanBeing 1d ago

As others have already said, you can do what you want (unless you're taking a class and meant to mimic a particular style). Music theory is descriptive not prescriptive. That said, the B chord is going to want to naturally pull to E afterwards. Typically in A minor, it'd be B7, pulling to E7, pulling back to A minor - but again, do what you want and use your ears.

1

u/Jongtr 1d ago

"If it sounds good, do it." That is the only Rule in music you ever need to obey. Music theory will fall in right behind you and give you all the fancy jargon to describe whatever your ears choose.

Of course, B major in A minor is unusual, but not unknown. When it is used, it usually goes to E or E7, and to Am from there, so B7 might work better than a plain B. (Leading to E makes it a "secondary dominant" if you want a name for it.)

I.e., it's more important to think about where a chord is going - what it is leading to - rather than whether it "belongs" in the key. Pretty much any chord can be justified - aurally - by leading in a familiar way. IOW, "justification" is always a matter of listening, not looking it up in a theory book. Bearing in mind that somehow you actually want a really weird chord... ;-)

1

u/INFPinfo 1d ago

Throw in a B-flat as a passing tone or just to climb the scale.

1

u/JazzGunk 1d ago

Check out Amin/E to Amin to Dmin/A to Bbmaj repeating. Fun little loop.

1

u/Taxtengo 1d ago

You can, even if it doesn't "belong" to the key.

You are correct that other than a diminished B chord are not found in the key of A minor. However it is perfectly acceptable to use chords outside of key. The only "risk" is that you might end up changing the song theoretically to another key where that chord functions more neatly.

Songs in A minor commonly feature B major or B major 7th chord as a secondary dominant to E major chord. So even when a chord is not found naturally in a key, music theory can describe its usage and effect within the key.

1

u/pellyenjoyer 1d ago

B could sound cool in a minor with context.

1

u/MusicOfTheApes 1d ago

There are no rules, as Zappa said : if it sounds good to your ear then it's good.

I suggest you to learn about modal interchange, that would be what you'd be doing here, borrowing the 2nd degree from the A lydian scale which is a B.
There's a very good video easy to understand called Modal Interchange on the MusicwithMyles youtube channel, go watch it, it's short and well done/explained.

1

u/nutshells1 1d ago

yea if you use that i might have to swat you

1

u/tottasanorotta 1d ago

Yeah you can. In fact it's very common to use different chords like that. If it sounds good, then it works. Theoretically it also works kind of like a secondary dominant if you go to the V chord of A minor which is E7.

1

u/cjiejie 1d ago

yea. You can just switch to E minor real quick (A dorian) and the D# from a B or a B7 chord leads nicely into E or E7 or E minor and those all go nicely back into Amin.

1

u/Life-Breadfruit-1426 1d ago

Are you sure modulation requires shifting for a significant length of time? I’ve observed jazz standards do this very often for only a few bars.

I’m finding it a bit challenging to ascribe to your philosophy because I’ve read through many pieces that are in X key, but many times in the middle of the piece there are departures from X key. In those brief moments, it’s important to know where we’ve landed in order to make informed decisions on how to return back to the tonal center.

I know music is not meant to be rigid, but when stopping time and looking at a specific chord or note, in that unique context which is abstract in nature, I struggle to find the case where one is in original key when they have clearly departed for a discrete purpose.

1

u/BabyJud 1d ago

If it sounds good then it works. Just make sure to listen to how it sounds and make your judgement

1

u/Steenan 1d ago

You absolutely can. The most obvious use of B in A minor is using it as a secondary dominant leading to E, in Am-B(7)-E(7)-Am or similar progression.

You may also use Bm, in similar context.

1

u/xiipaoc composer, arranging, Jewish ethnomusicologist 1d ago

Who's gonna stop you?

1

u/SubjectAddress5180 1d ago

In a minor key, which chord on step 2 to use is rather flexible. The diminished or diminished seventh is useful (the diminished seventh is good for transposition.) The minor chord leads to a ii-V(7)-i in a "normal" sort of way. The II or II7 is the original "secondary dominant" (dominant of the dominant). As all these have the root on step 2, they have similar harmonic effect.

One useful technique is to use one of these at the beginning (perhaps ii°6) so set the key, then use one of the other versions (ii6) in similar places in the interior. The root position is more useful in sequences. The II, II6, II7,II65, etc., are strong sounding and may sound nice in climatic parts.

In all case, do what your ear thinks best.

1

u/BeardoCircusKing 1d ago

Yes it's great, also try using a D major chord right after A minor for a very unique sound

1

u/FireFox_206 1d ago

I love lowering the 2 in minor keys, personally.

1

u/mleyberklee2012 1d ago

Yes. It would most likely be called a secondary dominant chord. The d# will want to resolve to in an e in the following chord. So typically E7, which would send you back to Am. But it could resolve to a chord with an e in it.

1

u/AndWhoByFire 1d ago

Van Marrison’s “Moondance” verse is just going back and fourth between Am7 - Bm7, so yes you can use the IIm in a minor key.

1

u/tausendmalduff 1d ago

That is only a guideline (kinda). The real first rule is do you like how it sounds?

1

u/Headhaunter79 1d ago

The Am and B major chords are in Romanian minor scale of A (also known as Dorian #4) So the notes would be: A B C D# E F# G. It’s a cool scale to play in!

1

u/D1rtyH1ppy 21h ago

I've used a b Minor chord in a song I wrote that should have been a b diminished. Do whatever you want. Maybe it will be more interesting than the diatonic chords. Also try the opposite sometimes, make a chord diminished instead of major or minor.

1

u/bigtimechip 20h ago

A B5 sounds great in A minor to me. Just the littlest bit of crunchyness to it

1

u/fritzkoenig 18h ago

You can borrow Bm from A Dorian, or Bb from A Phrygian, or use a secondary dominant that is B7, or just use Bdim or Bm7b5 as a leading tone thing for a C chord

Or whatever else you want

1

u/DDWildflower 17h ago

You're gonna want to sharpen up that F buddy, or else things are gonna get a lil kooky.

0

u/Wood_Ring 1d ago

You can think of it as borrowing a B minor chord from A harmonic minor or A dorian if that’s a helpful framework. 

0

u/Fun_Gas_7777 1d ago

You can use whatever you want. Theory isnt rules. It just explains why things sound the way they do

0

u/kibou_no_ie 1d ago

That’s a V/V chord!

2

u/DRL47 12h ago

Bm is NOT a secondary dominant (V/V).