Yep, you can learn a fair bit poking around with a meter, but a scope will give you so much more info, with single prod you can see a dc level, ac peak content, frequency content, distortion type simultaneously. In my book you will learn a shit load quicker. You will learn to recognise different types of distortion and frequency response etc. Once you use a scope well it's a bit like comparing fumbling around in a darkened room versus turning on the lights. You will find what you are looking for quicker and you will have a better appreciation of the unplanned behaviour of circuits that you couldn't hope to find with an audio probe or meter. There is a whole heap of possibilities between "yep the signal is there" to zip, nada, nuthin'...