Salut, saludos, and salutations, Harry (if I may call you that)! I have listened to your upload here and to all of your other uploads to see if you have the potential to create great Electronic Dance Music (EDM) in the (hopefully near) future and possibly other types of music as well. Your potential to create great music determines whether you get scouted or not in most cases here on Newgrounds. Without further ado and to skip this introduction; this is what I have to say:

After listening to your other EDM tracks that you have uploaded, I must say that I am quite impressed with what I have seen. Although some of your tracks are still remixes, they seem to be quite original and unlike anything that I have heard before. This can be both a good and bad trait depending on where you want to be as a composer and what perspective you view it in. So far, you have uploaded house songs to Newgrounds; this is not a bad thing, however. Let's talk about your track here, Duality:

Duality has a good melody, a good trance pluck, and is just overall pleasing to the ear. The kick that is used compliments each other instrument in the beginning.

At about 30.5 seconds, the snare that is introduce feels out of place and could use some filtering on its cutoff frequency. At about forty-four seconds, the high-pass filtering (I think I butchered the name) is too high and just makes it hard to hear. Consider playing music with that filter in a loud area like public transportation: most people would not likely hear anything if/when there is a section being played like that.

The synths at about 45.5 seconds sound very pleasing, but they just aren't loud enough really. They seem much quieter than anything else really and make the 'drop' look much less of a drop. Most house songs don't necessarily need a drop, but more of a refrain in the sense that sounds well.

At 1:15, the same pluck that is used is just used at a higher octave, making the pluck overtake everything else. This is something that you want to heavily avoid. At 1:45, the same snare that was used previously is back and still is out of place. The refrain at 2:00.5 doesn't feel so much of a refrain anymore since the one pluck is still louder than everything else.

The ending seems to just feel like a cutoff rather than an ending to the song. Adding a reverb, or echo, does help with ending a song, but it doesn't completely finish the job.

SUMMARY:
Overall, this is a pretty decent upload. You definitely need to work on your filtering, your audio balancing, and your endings. I see the potential in you to get somewhere, but only you can reach there. I am going to scout you on Newgrounds. Congratulations! I hope to see some great tracks uploaded in the future!