Voxengo tells us that Warmifier is a special plug-in which processes audio signal in a way similar to analog valve equipment. They say that, by using Warmifier you can achieve valve warming and 'console' coloration effects.
Warmifier is applicable both to the complete mixes and to the individual instrument tracks. You have several parameters at your disposal that allow you to control the strength and the color of the effect. Also, you have several valve types to choose from. Each valve type offers a different overall coloration.
While the effect of this plug-in is definitely subtle, Voxengo says that the difference it makes is similar to the difference in sound between different analog mixing consoles - in most cases, boiling down to adding a subtle "sparkle", "presence", "warming" or "solidifying" effect to a sound track it was applied to.
Warmifier 2.0 added the following features since version 1 (version 2 can be used in projects alongside version 1):
Pricing and Availability:
Introductory price of USD 49.95 will be effective for three weeks from now, which is 15% off the regular price of USD 59.95. Upgrading from the previous version costs USD 19.95 if previous version was purchased earlier than 180 days from now: otherwise the upgrade is free during this grace period.