Hi, Russell -

Of course, I'm having this image of how you're going to play both instruments at the same time...

Guitar and B-flat trumpet are one full step (two half-steps) apart. Guitar (and just FYI, piano) is keyed to "C", and of course your trumpet to "B-flat". So (and this is what confuses people) when you play a "C" on the trumpet, that's the same as a "B-flat" on the guitar (or piano). Trumpet music is written one full-step higher than guitar or piano music for the pitch to match.

So, let's say you're reading your guitar music and want the trumpet sounds to match, then you need to play one note up. The first column below is the note you see on the guitar (or piano) music; the second is what you would play on the trumpet to match what the guitar/piano is playing:

C --> D
C#/Db --> D#/Eb
D --> E
D#/Eb --> F
E --> F#/Gb
F --> G
F#/Gb --> G#/Ab
G --> A
G#/Ab --> A#/Bb
A --> B
A#/Bb --> C
B --> C#/Db

Try it - from the chart above, play a C on the guitar (or strum a C chord), then play a D on the trumpet. You'll see they match in pitch.

Now, if you are going the other way, where you are reading the notes on the trumpet music and want the guitar to sound the same pitch as the trumpet, then you need to lower everything one full step. The first column below is the note on the trumpet music; the second is what you would play on the guitar (or piano):

C --> A#/Bb
C#/Db --> B
D --> C
D#/Eb --> C#/Db
E --> D
F --> D#/Eb
F#/Gb --> E
G --> F
G#/Ab --> F#/Gb
A --> G
A#/Bb --> G#/Ab
B --> A

Try it - from the chart above, play an E on the trumpet and you'll see that you'll need to play a D (or strum a D chord) on the guitar to match it.

I hope that helped and didn't just confuse the issue.

John

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