Hay naku... I think the major difference is when you hear things tracked on 2", and mixed to 1/2" on a nice analog console. Once the mix hits hard disks no matter how nice your converters are, you'll never be able to hear any discernable difference. Which makes me think a more valid test would be:
PROTOOLS TDM vs. PURE ANALOG test:
1. Get one common studio, common mics, common instruments, common performers, and the takes should be split to 2 signals - one going to PT and the other to Analog.
2. Use mic splitters to two signals each- one to analog, one to PT.
3. Dapat ang mix may GOAL - say, "I want the mix to sound like <place pre-Protools recorded hit song here>"
4. Use strictly outboard equipment for analog on a quality board like an SSL, Neve, Amek, etc.
5. On PT, use plugins strictly, and ITB mixing lang.
6. Mix analog 1/2" and listen to the final 2-bus mix. Compare to ITB mix of that of PT.