“The Trombone is the only instrument that in theory can play in perfect tune, but in practice never does.”
- Sokrates, March 17, 421 B.C.
Luckily, since his days, trombones has evolved and are now made of metal instead of clumsy and heavy marble. And many trombone players have learned to actually play in tune as well! But Sokrates was on to something. Since we have a slide instead of valves, we can actually adjust the pitch and make it perfect without compensating with the lips. On a valve brass instrument, you have to do the work with the embouchure, or maybe a trigger on some notes.
So, what about that 20 positions trombone???
While most text books and teachers argue that the standard trombone has 7 positions, I would say that any trombone in practice has more than 20 positions, so the trombone on the picture is actually your trombone!
There are tones on the trombone where you have to adjust with the slide to play them in tune. A good example is the high G on 2nd position, where you have to adjust the slide to somewhere in between 1st and 2nd position.
Try playing G, B and D on 4th position without moving the slide it on your trombone. Can you hear that it is out of tune? Now try it with small adjustments and make sure every note is in pitch.
Take a look at the slide chart below. Here you can see that there are many variations of each slide position, depending on the note you play. You should be aware of all the minor changes and try to incorporate it into your playing without having to think about it.
Intonation of major triads
Now, to make it a bit more confusing, you might know that in general when you play a major triad, the third should be kept down and the fifth should be kept up. Looking at for example the G major triad on 4th position, I just suggested that on the trombone, you should keep the third (B) up a bit and the 5th (G) slightly down. This is basically the physics of the trombone overruling the standard intonation practice of triads!
So, in practice, is this how pro players make sure that they play in tune? No. Not really. It all comes down to being able to hear the note you are about to play before you play it, and have the correct pitch in your head. This way you can actually play in tune without having the slide in the exact position. But knowing about about all these sub-divided positions will help you hit the pitch you are aiming for.
So when playing in an ensemble, there is only one way to play in tune:
Listen, listen and then listen some!
PS. Remember that when play a long note, you might actually have to correct the pitch half way if the chord is changing! Try playing these two chords with some fellow musicians and see what happens with the top note when the other two change.
Have fun playing in tune!
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