You're welcome!

Originally Posted by: cj.stevens

While we're on the subject can you point me to some basic music theory on the GT site - or could you recommend a beginning music theory book.

Absolutely! In general the GT courses will show you the theory you need to know as you progress through the course. I also encourage you to start with these tutorials on intervals & basic scales at you convenience. But don't neglect the course!

Intervals

https://www.guitartricks.com/tutorial.php?input=362

C major scale

https://www.guitartricks.com/tutorial.php?input=363

A minor scale

https://www.guitartricks.com/tutorial.php?input=445

C minor scale

https://www.guitartricks.com/tutorial.php?input=446

Then a little chord theory & how scales & chords are related.

https://www.guitartricks.com/tutorial.php?input=426

Putting it in practice with major.

https://www.guitartricks.com/tutorial.php?input=427

And minor.

https://www.guitartricks.com/tutorial.php?input=428

Then you'll be ready for this basic intro to music theory.

https://www.guitartricks.com/tutorial.php?input=495

And the circle of fifths.

https://www.guitartricks.com/tutorial.php?input=835

Just about any book on music theory for beginners is fine. There are hundreds of them on Amazon or in any large book store. But the most important part is to connect it to application: to put the ideas into practice.

So, I recommend the above tutorials & this nifty website that concretizes the concepts.

https://www.musictheory.net/lessons

How far you go depends on your interests & goals. And it's important to remember that your theory knowledge learning should roughly match your technical skill learning. Theory that you can't put into practice is useless & confusing. Skills that you don't understand the idea behind are often frustrating deadends. So the optimal approach is to keep them growing together, supporting each other.

Hope that helps. Please ask more if necessary & best of success!