Amusing
This game is rather daunting, the original was so simplistic and easy to use, but while the second definitely improves on a lot of things, it also utilizes some very unnecessary features.
First things first, the graphics are very well done, in the same style as the first, simply more polished. The layout is quite different from the original, but I would call it an improvement overall.
The sound in this game is great, and there is an enormous amount of options when making the music. Some would call it overly technical, but at the same time, it was obviously required for this game to not be the simple 0-9 numbering the first had. Unless you want to scroll through numbers in the hundreds that is, so good decision on your part.
There is a problem however, the shear size of this game causes a lot of lag (I even experienced some in the offline version). It's a shame that something can flow so well one minute, and on the next replay, there is an entire second bump of sound that distorts everything, making consistency difficult at times.
Even so, it's hard to make a negative out of "your flash has so much content it crumbles under it's own weight" but that's really the only sound issue.
As far as gameplay goes, it's a little disjointed, this game would be enjoyable purely through the amount of sound options, a story mode and Guitar Hero-ish game was not necessary. It's not quite a bad thing, it's just so out of place that it's kind of disheartening you spent the time to add in so much, and yet I couldn't find any enjoyment out of it.
That being said, you didn't do something bad that a lot of sequel makers do:
That is to add in a ton of new features but forget the core gameplay basics, you kept the actual music making part the same, but just with more content, and that's all anyone should expect.
Overall, you have an aesthetically pleasing game, both in visuals and sound. All issues are minor and you should be proud of this sequel.
9/10