Now that the new Host makes it easy to use Reason liberally, there’s one thing about using Reason with VCV I want to point out: it’s a great way to make CPU-efficient patches, so long as you know which devices to use, because VCV’s CPU meter won’t be able to tell you which Reason Racks are eating all your CPU budget.
Past the first VST instance, Reason seems to have no significant per-instance CPU cost. So you can safely use a lot of Host instances containing very few Reason devices.
Reason has been around for 20 years, and while I have misgivings about their current dev practices, there’s one thing you gotta acknowledge about them: they have a solid track record not to kill off their old tech willy-nilly. In fact, I think there’s only really 4 major techs they’ve truly killed: ReWire (favoring VST integration instead), ReBirth (Roland suddenly realized their old 303s and 909s were a license to print money rather than an old embarrasssment), Line-6 amps (some deal with Yamaha fell through), and Balance hardware (but their unmaintained drivers still work).
Almost everything released in Reason 1 is still in Reason 11. And in 2000, the clock speed of your average single-core Pentium III was expressed in MHz, not GHz. In other words: the older a Reason device is, the more aggressively optimized it’s likely to be. On the other hand, some more recent devices - especially third-party rack extensions - are big CPU munchers. For the budget of a single instance of Europa, I could run a dozen of Thors - and Europa sure doesn’t sound 12 times as good as Thor.
Now, if you haven’t used Reason for many years, you might not be sure which devices are old or recent, so here’s a handy list of older devices that are likely to be aggressively optimized.
- Thor (CPU usage depends on submodules used)
- NN-XT (In general, using samples is not expensive on the CPU)
- Dr OctoRex
- Every single half-rack effect (RV-7, DDL-1, etc)
- RV7000 MkII (I am not sure how well optimized the newer convolution mode is)
- Scream 4
- MClass series
This is far from being an authoritative and well-researched list, and more recent devices are often well-optimized, but make fewer optimizations that trade-off sound quality for speed. But some third-party offerings have a CPU cost disproportionately incommensurate with the sound quality they offer.