1. thats definitely true. The best mastering can not compensate a poor mixdown.. What I was trying to say is that after your mixdown, there will be another stage of compression/limiting, which will usually reduce the dynamics. So you have to figure out and test how the track actually would sound like if there was a mastering compressor/limiter on the mastering stage. So lets say you compress some of your single elements too hard, and it still sounds alright on the mixdown... but these effects will show even more during the mastering stage.

2. Usually yes. The mixdown peaks at lets say maybe -3dB (figured out this is a good value), and the master peaks at -0.2dB (some kind of 'industry standard' for trance tunes), thats a reduction of headroom of course. Very often there is quite hard limiting and compression used during the mastering stage which means the track sounds more upfront and in your face... but there will also be a reduction of dynamics. The key to a good master is to find a balance between bringing the track upfront and maintaining the important dynamics.

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Cybernetika albums (free DL): Atropos (2009) | Nanospheric (2008) | Neural Network Expansion (2007) | Promo #1 (2006) | Paralysis (2005)

homepage: http://www.cybernetika.de