Exactly this. The most astounding difference between MP3 and FLAC I've ever heard was Teen Spirit by Nirvana. In the opening riff there's just such a huge difference in depth and clarity. On the MP3 everything sounds flat and lifeless, on the FLAC recording you can hear each individual thrum, every single vibration as the song spins into life. There's nothing quite like listening to lossless Nirvana through some nice headphones/speakers.