What exactly do you mean by a big room reconstruction sound?
Overlaying more sounds over a tune? Im guessing that a lot of producers that would do that already have the tune split up into parts like you would for a remix. Id be careful of adding too many synth sounds to an existing tune as you are more likely to make it sound worse.
Unless the tune is quite sparse as it is of course so there is room for more frequencies.
If you were to do this though then you would load the original track into ableton and warp the track accurately.
Then you would open another midi track along side and load a vst onto it (like nexus for example) then you could overlay any extra sounds you like. Then export it all as a wav file to dj with
If you listen too those tracks some one made a Big Room Reconstruction. I was also on Markus Schulz twitter and found an image of him using Ableton live with Nexus VST loaded on screenshot and the caption was something like.. 'big room reconstruction track :P'
There was an imported MP3 at the top
a few bars (channels) down.. there were lots of added notes maybe 5mins into the track like an added on bass sound.
Any ideas of how I can get something close to a cold harbour big room sound?
With lots of practice along with good use of vsts im afraid. Lol. Big room sound reconstruction will be just his name for a remix or re edit.
It is possible that the imported mp3 was a reference track for him to compare the sounds he was making to (good practice as it shows you how close your sounds are to existing pro tracks).
Check out the beginners guide to tools software and production tips i made if you havent already, there are plenty of links in the post to tutorials and it explains guite a lot.
Of course be sure to keep asking questions here as we all love to help.
Just be sure to ask more specific questions about each part of a track like leads, bass, drums etc. Because no one is going to be able to give you an easy answer to how to produce a big epic pro trance track.
To get anywhere near the kind of sound you are after takes a lot of practice and dedication, making music whenever you have chance. It is difficult at first but very rewarding when you start to make music that you and others are pleased with!