Building muscle memory for playing chords by ear, with piano chord inversions

Question

I've started to practice ear training in order to be able to play chords by ear... while playing melody by ear is pretty easy for me, playing chords is harder. I started with the simple I-IV-V chord progressions and also I-vi-IV-V progression.

While playing melody by ear requires a straightforward muscle memory (when the pitch goes high the hand goes high and vice versa), playing chords by ear requires some undefined muscle memory: you can play the chords on different octaves, or even use chord inversions. sometimes the same transition between chords will be in the up direction and sometimes in the down direction.

for example I can play the I-vi-IV-V progression in this way;

CEG---AlowerCE---FAupperCupper---GBDupper

OR I CAN PLAY:

CEG---AupperCupperEupper---FAupperCupper---GBDupper

OR I CAN PLAY(with inversions):

CEG---AupperCE---CFAupper---DGB

and many more possibilities....

In each way, the hand and fingers are doing different movements. So how can I build a muscle memory that links all the different chord shapes with the overall sound of each chord ...

Answer 1

You're assuming a basic simplification of muscle memory for melody, but that's actually a bit more complex: it's not just about moving fingers on the right or the left, you also need to know the interval, which may cause switching black/white keys.

For instance, a basic movement that plays a minor third may start with the right hand thumb and either use the index or middle finger for the second note depending on where each note is: for white/white and black/black keys, you may prefer the middle finger, while you could opt for the index when switching "key colors".
In fact, that choice may change depending on your hands: the proportion between your hand bones, how "thick" your fingers are, and how much your technique is developed.

The position of those notes related to your body is also important: for example, continuously switching between two notes a fifth apart may require you to use different fingers depending on their pitch.
Try to alternate C/G with your right hand on the higher octave of the piano, and then do the same two octaves below the middle C: you may find out that it would be easier to do that with thumb+ring (or middle) fingers in the former case, and probably index+pinkie in the latter.
Now do the opposite with your left hand.

The situation can only become more complex when dealing with chords and progressions.

Even if similar inversions and chord relations may have similar hand/finger movements, progressions involve much more complex aspects. The same chord type may use different fingering depending on the fundamental. And the same progression may require different fingering too.

Considering the above example, you may need to use the middle finger for the third degree (while you'd normally use the index for that chord), because in the next chord it would make more sense to switch to the index for the second note of that chord.
Another progression may require you to use the index for the first note, instead of the thumb.

The actual length and tempo of the progression may cause different fingerings too: a basic chord switch may be easier when dealt with as a stand-alone progression, but it could create issues for the next change. When playing at slow tempo, you may be able to use more comfortable positions, but if you need to play faster, you may require a smarter fingering.

All this means that you need a higher abstraction layer that considers both the progression and the "finger layout" for a specific chord based on its fundamental (or inversion). And that can only be achieved by practising progressions at different keys.

At some point, your brain will start to learn a deeper level of "muscle memory", probably split in two types:

• a simpler one, used for common progressions that you practised enough;
• a more complex one, that eventually intervenes when the above fails (because you don't have a basic muscle memory for that progression), based on the sum of abstractions related to degree/chord relations, key positions, etc.;

As time goes by, more cases of the second will become part of the first.

Simply put, the "muscle memory" you're referring about is a very simplistic sequence of movements based on extremely simple changes: for instance, a specific virtuoso passage that fundamentally is a "list" of well defined and precise movements.
Chord progressions are not like this.

So, I believe that the only proper answer to your question is: practice, and a lot.

Answer 2

Simple answer is - loads of practice! Get used to moving l.h. from any chord (start with basic triads) to any other. You may decide to start with root position to root position. You may decide to keep a common note, and move other fingers around that.

The more you look, the longer it will all take, so try to do this without the visual guide. Another ploy is to be able, without looking, again, to be able to play the three inversions by spacing your fingers for each before hitting the keys. Doesn't have to be a particular piece. You could write out C, F and G on three bits of paper, and turn them over at random, then play what you see, in whatever inversion you decide.

When that's good for all 24 triads, then move on to 7ths: that's a load more, with m7, M7, dominant 7, diminished 7, m7♭5, Mm7 to trawl through!

That's a lot of practising, and unless someone knows differently, the only way. It should come eventually, but when that time is, is impossible to say. It took me years.

I've only really addressed the l.h. in this answer, forgive me if I misunderstood the question.