I've been practicing alot of easy songs (amazing grace, love me tender, small world, you are my sunshine, etc.) in C major. I do this by ear and I've got the melody and the harmony/chords down.
Now I want to try these in different keys. Should I just go up the circle of fifths (C,G,D,A,E,etc.) until I can play a given song in all the 12 different keys? My goal is to just know how to improvise and jam with people in different keys. Is this good practice?
Is this good practice?
IMO that's a good approach, but make sure you are paying attention to what you're playing, and learning from the material: How the chords and melodies change in sound and construction, and the ways in which you have to alter your playing techniques across the different keys. Don't just play them off by rote. I practice a good deal like that - much more interesting than playing abstract exercises. (Which are also important, especially when you analyze and learn from them.)
But to develop your skills more deeply and more comprehensively, you might want to make sure that you are using a collection of songs that use different forms and types of progressions: 12 bar, 16 bar, 8 bar; I/IV/V , II/V/I; different types of bridge parts, etc. That way you learn how those various forms and progressions are played and how they work in the different keys.
From your selections it does appear that you have some variety, but maybe formalize it a bit: For example, make a list of songs you like to play (If you like to play something, you're much more likely to stick to your routine) that you know give you a decent array of forms and progressions. You'd probably be covered pretty well with 15 or 20 songs. Take four or five at time, for example, and play them in C. Then the next 5, until you get to the end of your list. Then move to G, or F, depending on if you want move in the sharp direction (clockwise) or the flat direction (counterclockwise).
If you select your material well, when you complete the whole cycle with all of your selections, you will feel really good about your accomplishment and will have learned a lot in the process. Then do it again - repeat a couple of times and then maybe try it in the opposite direction through the circle or some different order that you find interesting.
To complement the above, it's also a very good idea to play along with a rhythm track. It makes your practice sessions more interesting, more realistic and gives you more ways to challenge yourself: For example, keeping raising the tempo as you get more familiar with each key. Even if you'd never play the song that fast, you will develop your chops. Also experiment with different rhythms - any song can be worked over with any sort of rhythmic groove - try a jazz version of 'You are my sunshine', a samba version, an RnB version, etc. Sometimes it will sound good, other times not so good - work to make it sound as good as you can. (True - Amazing Grace with a samba style rhythm section at 130 BPM will probably never sound very good, but you never know - be adventurous and give it a try.)
With a rhythm track behind you, it will be also be easy to add a 'piano solo' verse to songs, where you improvise on the tune as if you were playing a solo - another way to keep it interesting, expand your knowledge and ideas, and help you when you're in a group setting, when very often (too often...) soloing a is big part of playing together.
Playing with others is always the best way to improve, but you can do great deal on your own if you learn how to challenge yourself with structure, discipline, milestones, goals, and of course experimentation.
If you take that approach for a while - 6 months might be a reasonable period - when you go to play with others you will feel confident that you are up to the task, and you may even find that you have the edge on a lot of other musicians.
Good Luck!
Should I just go up the circle of fifths..?
If you change keys along the circle of fifths, the difference in fingering between key changes will be "gradual." So, for example, the fingering difference from C to G major is small. In the beginning this can be good, because it will help ease you into the new keys. But you may reach a plateau - like I did - where this isn't challenging and the exercise becomes less effective.
If you change keys chromatically - example C, Db, E, Eb, etc. - the fingering difference between keys is bigger - no sharps, 6 flats, 4 sharps, 3 flats, etc. This presents a bigger challenge fingering-wise, because there is so much difference in the fingerings.
You might try both sequences. Starting with the circle of fifths and then moving up to chromatic.
Stinkfoot has it all covered! I underline the 'not just learning some songs so I can play them in different keys'. Use the songs as vehicles, to recognise chord progressions - i.e. Dm>G>C is the same progression as Bm>E>A, as Fm>Bb>Eb, even though on keyboard they will never look alike. (On guitar, they often can and do!). Knowing what the vi of any key is (Am in C, C#m in E, Fm in Ab) is can help find your way round harmonising; feeling that the next part of the tune needs to be V of V (D7 in C, Bb7 in Ab, G7 in F) etc., etc.
To be able to play any song in any key is a powerful tool to have. I play with lots of musos, and it's frustrating when a singer can't sing in the key someone's learnt a song in, and the other players can't simply change to a suitable key. Go for it!!
The circle of fifths has nice properties in terms of modulation, i.e. it is a musically meaningful way of practicing. So that would be a great start.
To keep concentrated, a very effective means is to say out loud the name of each chord while you are playing, or even say or sing out loud the name of each melody relevant note. This way of working trains your brain to actively associate each note name or chord with the corresponding sound, in each scale. Don't worry, this is not easy, so take it slowly at first.
The best part of this exercise is that you don't need an instrument in your vicinity: a table, your hands, the leadsheet and your voice are enough.
FWIW I play (mostly improvise) in a different key every day, based on a formula:
1 add day to date (today is 7/25, so sum is 32) 2 repeatedly subtract 12 from this as long as you don't go negative. 32-12=20, 20-12=8. (In math this is the same as the remainder when dividing by 12, aka modulus.) 3 starting on the A note, count up from ZERO (A=0) until you reach the Key Of The Day (for today, 8, it's F, a fun key to jam in)
The description above sounds complicated but it's actually dead easy. On a piano, counting chromatically up from A is simple. Over the year, it averages out fairly uniformly.
Playing in a new key every day leads to some wonderful discoveries. Hope you're inspired!
Personally, I think we've entered a new era with digiatl keyboards that offer transposition capabilities. You can continue to develop a repertoire (i.e. tunes with chords you know by heart) and use the transposition capability to always think in C while coming out of the speakers in any key.
I knew a pianist with perfect pitch that would have gotten headaches from this idea but most of us and just use this "capo" trick like the guitarists so to make their chords fit with a singers vocal range on demand. The capo cn only raise the key but the digital piano can go up or down and still deliver a useful sound.
One of the teachers on the web of "perfect pitch" and ear training advises training your ear to duplicate songs by ear in the key of C before exploring the other 11 key centers.
If you can duplicate on demand any tune quickly by ear in C then adjust the root center by automatic transposition you'll be useful a lot sooner than learning basic repetoire in 12 keys. Since when the task demands it only 1/12 the work will have much value.
Of course, the longer road the mastery of all keys is required for anyone wanting to be taken seriously as a master of music. Just decide on the end point and pick the path that leads there with the fewest steps:
Product a keyboard arrangement of any tune in any key - use the digital capo and find the shortcut
Be able to step up to a traditional piano and do the same - get to work mastering music theory and the develop your musical memory to play any tune in any key in any style. No real shortcuts to "pass Go and collect $200" on this path. Just a ton of serious hours learning the craft.
