Keep in mind that the Tyros series of keyboards does not have onboard speakers. The optional speakers, which are well suited for the keyboard, work great in a studio setting, but just about useless in a large venue. And, what you hear from YouTube is recorded via another system. Therefore the sound quality will depend upon the recording system, mics used for recording, positioning of the mic(s), crowd noise, and a host of other factors that will have a dramatic influence on what you hear with a demo. And, of course, your playback system will have a significant bearing on what you, as an individual consumer, hears. I use a Yamaha MS-50 sound system with my PC. It does a great job. However, when I hook up the Logitech Z-5500 system to the computer it's mind blowing.

As I've said in the past, unless the demonstrations use the Line-Out of the keyboard directly into the recording system it would be extremely difficult to make a judgement call about what you hear from the demos. If the line-out IS used, then you can use the sound system that you would normally employ in the studio, or on the job, thereby providing you with a realistic idea of what to anticipate from the keyboard.

Cheers,

Gary