First off, let me say that I really hope this thing doesn't "auto-play" when people look at this thread.  By itself, it is about as interesting as yesterday's oatmeal.  Hopefully if the forum is still doing that autoplay thing with mp3 tracks, Pierre can maybe set this so it won't.

This is typical of the sort of file I have on a little portable media player that I can tuck in my pocket or the violin case and use to practice pretty much anywhere.  It is very simple, just an A in the lower range and an 80 beat per minute kick drum beat.  It does have a few measures of silence at the beginning to allow time to pick up a bow and get ready to play, and has a 4 beat "count off" of closed high hat clicks at the beginning, and then it finishes out with 4 clicks at the end.

Ok, so now that I've explained what it is, what can one do with it?

Well, you can simply walk up and down A major or A minor scales, for example, doing nice even quarter notes, one to a beat.  The reference note is on the first beat of each measure, which I find to be plenty to avoid drifting off intonation, but not so constant that one might get too dependent on having a reference note to play against. 

If that feels too easy, and the beat too slow, then do two notes to a beat or four notes to a beat, or etc.  One also doesn't have to just walk up and down a scale.  You can do patterns of notes, arpeggios, or free improvisation with the notes of the scale, or you could work on some tricky parts of some piece you are learning that happens to be in the key of A major or A minor.

Working scales against a reference note is good, I feel, for developing the ear for recognizing the intervals in a scale and how they sound against the root.  So it can be a little bit of ear training as well.

I usually use it playing by ear, but it could work just as well with a written etude for A major or A minor, giving it a tempo to work with and a reference note to occasionally check your intonation against at regular moments.

It is about seven and a half minutes long, because I personally feel that makes a good practice "chunk" for me.  Shorter than that, it feels like a maybe didn't work enough, longer and it starts to feel like it is dragging on for a long time.  So this length is in my "Goldilocks" range for a practice chunk.  LOL

It works out to being about 160 measures long, which is enough that I think most teachers would consider it a reasonable part of a good practice session.  I usually do two runs of this a day, with two different reference pitches, like A and E.  That way I've put in 15 min of scale practice and covered usually 4 keys (A major and A minor, E Major and E minor, in this case). 

I usually aim for a 45 min practice session every day.  So I start with 15 min of open bowing (broken down into 5 min sections), then I run a couple files like this one to get in some scale practice, and then I'll do about 15 min of work on some technique(s) I want to get better at.  For me personally, that usually feels like a nice little workout with plenty of focus building basic skills, and I usually feel like I'm in pretty good shape when I pick up the instrument to play songs/pieces later.

But anyway, this is a very simple sort of tool that can be used in a lot of ways to practice things ranging from easy to challenging.  I like having a bit of structure to work with, but where I can feel free to adapt my practice to what feels like it needs work or go in some depth on something where I may be getting a little bit of a breakthrough, to get the most out of it that I can.

Just figured I'd share it as an example of how one can make a simple tool/toy for practice and give some ideas on how it can be used, in case it might be of help to anyone looking for something to try.