“How many Time Slots does the new TDM II bus on Pro Tools|HD have? Are there any differences in the way those Time Slots are used versus the way Time Slots are used on a Pro Tools|24 MIX system?”
Okay, all you non-tweakofile Pro Tools users can probably skip this one, but it’s actually a fairly important question to heavy duty Pro Tools users.
TDM II is really quite a different from the original TDM architecture, so it is hard to make apples to apples comparisons. While in the absolute worst case TDM II “only” has twice the slots (at a 48 kHz Sample Rate), however, for many real world sessions it really is much more than this.
First, TDM II is a bidirectional bus that has 512 slots running “down” the bus and another totally separate set of 512 slots running “up” (in a sense this is really like having 1024 slots). Also, slots can be “reused”. Meaning that if you need a connection between DSP 1 to DSP 3 and another connection between DSP 5 and DSP 6, TDM II will just use a single slot. It is not uncommon for slot “reuse” to result in 2x to 4x improvement in slot usage, although it will definitely depend on the session.
Putting these two factors together it is highly unlikely that slot usage will be any kind of limiting factor in Pro Tools sessions for the foreseeable future.