You stated that you sound good at the beginning of your session. Maybe that's it. You are already in the mind set of content and you settle for what you have in the first 5 minutes and then loose interest. (either consciously or unconsciously). Keep a focused attitude beyond the 5 or 10 minutes. In fact, the first few minutes of your sesison should technically be a warm up anyway for things to come later on in the day (that's me anyway).
Just a thought at midnight in the middle of writing philosophy papers of all things.
Keep at it. Try to play for a longer period of time each day until you can hold down a full hour of practice. If you get tired use your little breaks t familiarize yourself with a piano. TRUST ME it will help alot in learning music (unless you already know it). Then you can spread out those hours through the day. ME? I do an hour in the morning before class, 2 hours after class then an hour in the evening (when there arean't any rehearsals).
Eric
__________________
Eric Sproul
Practice is like filling a leaky bucket
Bb: Yamaha Xeno 8335
C: Bach Stadivarious 239L and 25A leadpipe (Owned by Eric Sholtz)
Flugel: Yamaha Bobby Shew 6310Z
Mouthpieces: GR tech
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