Just picking on a few things in this thread.
First, the issue with most 2.1 speakers is the main left/right speakers the drivers are to small to handle mid-range frequencies, because of this they are not so good for vocals in music. Couple this with the fact most 2.1 speakers there optimised for games and films that tend to have an emphasises on very low and very high frequencies.
However there is nothing wrong with using 2.1 speakers for music, providing you are using good quality main speakers that are already suited to music.
I'm using Yamaha desktop speakers NX-E700's with a range of 60Hz to 28kHz, however I have a small sub that provides support under 60Hz. My sub is set to provide gentle support, remember the No1 rule with a sub is that it can't be heard, and should only noticed it's present when it's disabled. I listen to Amazon music HD, and if I disable the sub the music is definitely worse, my source is a Essence ST sound card.
Also, one of the most important things is getting the speakers on stands (position, height from desk, distance from wall, distance from each other, toe in angle to listener), and also isolate them from the desk. If you search some of my posts I've written quite a bit about this.
* All the above is in relation to desk / office speakers, in my main room I have a full separates system with Yamaha floor standing speakers that go 30 Hz–36 kHz, and rear field / surround speakers. If you run large enough main speakers you often don't need a sub.