In my last two posts on scales, I focused on using scales for (1) improving bow control in tone production and (2) improving musicianship through counting and cross-rhythms.
Scales are, of course, useful for improving a multitude of things--just about any aspect of cello fundamentals, or of building musicianship. A main argument my book, Cello Practice, Cello Performance, is that "technique is art"--everything is part of the same goal.
One of the biggest goals for most of us is learning to play fast, particularly in the upper register. Scales provide a great opportunity to work on just that. The following exercise, which I call "Divisible By Four," adopts the same slow-bow tactics as Part 1 of my series on scales, but by dividing the bow by ever-greater multiples of 4, gets the fingers going faster and faster.
Set the metronome to quarter/crotchet = 30bpm and play a scale, 4 notes to the bow. (I chose D major in 4 octaves; any scale and any number of octaves will work fine.)
Keeping the metronome at 30, take the scale twice as fast by slurring 8 eighth notes/quavers. Then 16 16th notes/semiquavers. Then slur 32. Then, if you're feeling exceedingly brave, 64. (This one takes a bit of practice to learn to do with your best sound.)
I use the Divisible By Four scales workout almost every day because it covers so many fundamentals. But it's also important to work on speeding up the bow, so you should also work on these scales using separate bows and the détaché stroke.
Of course, it may be hard to do the 64th note/hemidemisemiquaver pattern with separate bows straight away, which is why I recommend using the "Two Steps Forward, One Step Back" technique from Cello Practice, Cello Performance p.46.
Put the metronome on at around 80 bpm, and play up and down the scale in sixteenth notes/semiquavers, four notes to a beat. After you can do this easily, put the metronome on 90 and try it at that speed. It may be a little bit of a scramble at first, but work on it until it's slightly easier. Then take the metronome back to 85 and notice how easy that feels. You just taught yourself to be 5bpm faster!
Continue going "two steps forward" and "one step back"--95, 90, 100, 95, 105...all the way up to 120 or so. The trick is to give yourself time to get good at each tempo.
Check: are you playing with optimal relaxation? There is no point in teaching yourself to play with tense, stiff habits. Review Part I, "Fundamental Principles," of Cello Practice, Cello Performance.
The advantage of playing your scales in this way is that you never get "stuck" at just one tempo, but rather have the flexibility that you can play at many tempos.
The possibilities for improving bowstrokes in scales are endless. Just one example is how we can use scales to work on one of the trickiest strokes to master--uncontrolled spiccato. (For more about this stroke, see my article on it in the June 2016 edition of Strings on how to practice it in the context of Elgar's cello concerto, second movement.)
It can be good to practice the stroke using many bowstrokes per pitch so that you can work on it without feeling rushed. In the example below, I start with 8 strokes per pitch. Without changing tempo, you then play 4 strokes per pitch, so that your bow continues playing at the same speed, but your fingers speed up. Then 2 strokes per pitch, and finally you scamper up and down the scale with 1 bowstroke per note. Don't feel discouraged if you can't do the last one right away--these things take a lot of time.
These are just some of the ways we can use scales to speed up both hands simultaneously. I'm a big fan of getting both hands working at the same time, whether you're working on getting your left-hand fingers faster or your bowstrokes more coordinated. As I wrote in Cello Practice, Cello Performance, "the best sautillé bowing will be useless if you only practice on open strings, because the minute you stop the strings with the fingers of your left hand, you won't be able to perform the stroke any more." When playing scales, look for any opportunity to give yourself a both-hands workout, even if the goal of the day is to improve just one aspect of fundamentals.