Well, I have another post for you today off of the back of a couple of folks emailing me with similar questions, so I thought I’d share the responses. Thank you for your questions and emails, by the way – keep them coming!
So, a couple of folks have emailed me recently* concerned that their playing volume is not sufficient enough.
I can understand that this may be a concern if you’re playing just for yourself a lot, and with little feedback perhaps from a teacher or an audience of some description.
We all know that compared with some of our electrified siblings or bowed string cousins we’re a lot quieter, with notes generally decaying a lot quicker. If playing in ensemble with other instruments, then yes, we want to make sure we’re playing out and in balance with other, potentially “louder” instruments.
Other than that, I’d say don’t concern yourself overly with volume in an of itself. Volume, or dynamics, when playing guitar (or any other instrument for that matter) is all relative really. Its a case of making sure your fortes and fortissimos are somewhat louder than your pianos and pianissimos. Those will vary from piece to piece, with differing styles, genres and eras of music and even within a piece too.
If you’re not working with a teacher (or even if you are), I suggest playing for others and experimenting, asking them how you sound, how the dynamics come across.
Think about what you’re producing, how you want the music to “speak” to your audience, and – of course – the quality of the sound you’re making.
Keep tuned in to what you’re playing and the rest will fall into place.
* Thank you – you know who you are!
Classical Guitar n Stuff 
I usually play guitar when I’m alone to relax and have fun so I don’t place much importance in the volume. I paid much more attention to my skills and rhythm. But I imagine it would be different if you play with an audience. Cheers.