Now this. This is awesome stuff. Man, I found out about you out of nowhere one time when looking for songs to post on the frontpage and boy am I glad I did! You're a wonderful music artist and I'm highly impressed with your work. I don't usually review Newgrounds songs when I have so much to do, but I'm totally making an exception for you, who not only reviewed one of my tracks and at the very least deserves a review in return, but makes fantastic music like this.
Right off the bat, tight mixing, man! Fantastic low end. At high enough volumes I can definitely feel a well-balanced rumble that doesn't overpower everything else. Tasteful use of compression, which isn't too excessive. Not only that but everything is so clear, especially the drums. If there's one pet peeve I have, it's when people drown their drums out in the mix and all the other instruments cover them all up (this is especially common in some metal tracks) but here that's not a problem. The drums are excellently incorporated and have a lot of clarity. On top of that, everything else is given its own space to shine. Bravo.
I love the composition in this. I don't really know why. It's certainly relaxing as you've described, but at the same time it certainly has its own energy to it and I would definitely imagine this in some space-related game. You've got a remarkably good sense of composition and your melodies are undeniably catchy. Great melody at 1:29, and I love how at 3:19 you use it to end the track. This is all very well-thought-out and clever. The only thing that I felt wasn't very creative was the use of that terribly generic drum'n'bass rhythm for the synth plucks that start playing at the very beginning and play for a lot of the track.
The sounds are great. You've got a lot of high-sounding fluffy instruments here, contrasted beautifully by the thumps and rumbles of the drums and bass. Your sounds in general are very pleasant to the ear and well-chosen. The only sound I'm not a massive fan of is the snare. It's very hard to get the snare right regardless of what genre you're making music in, and over here while I still like it, I think it's a bit muffled and could do with being a bit brighter. At first I thought it was too rough for this track but in retrospect it actually works really well, so if I were you I'd just make it a bit brighter and not as muffled.
And the transitions! I love them. You use drum breaks quite a lot, like at 0:44, 1:06, 1:49, and so on. However, you don't excessively milk it, even if you use it a lot (probably because it inarguably sounds cool). It makes for some fantastic transitions. Do watch out that you don't overuse it in your future tracks though, because you use habitually after every handful of bars here and it can easly become a habit. That being said, everything is extremely smooth and flowing. The song effortlessly rides from one section to the next. You sure know what you're doing.
The intro is excellent, and I love its progression. The ending is also nailed, so no problems there. The only thing left that I feel I need to mention would be that the drums in general are pretty good! I would've liked it if the hats had some more presence in the mix and were more interesting, but who am I to talk, my hats are usually duller than a Monday morning. I think the drums did get a bit repetitive and tiring though; that's one thing to work on possibly. The drums at 2:35 were a breath of relief, because as much as I like your drums, I think some more variety in beats, rhythms, and sounds could've been good. In fact, if you want to be really creative, try adding some glitch effects, filter automation, all that good stuff! It'll definitely make the drums more interesting.
All in all I don't really have that much to criticise. This is just a considerably well-made and well-balanced track. I don't think it's perfect; it doesn't have that much replay value, some elements are too repetitive in nature and there are a few other minor issues, most of which I've mentioned above. Honestly though, this is very solid. I love it and I think you did a great job on it. Thanks again for leaving me that review and keep up the splendid work!