That's the catch - it is not going to be a set price addition to an MSRP. I'm sure THX has some basic pricing structure for products, although I would assume that they put together a specific price to certify each individual product being submitted for review. The most important variables that affect the consumer's pocket book are what type of product it is (a surround processor would be more expensive than a power amp, for example) and how many units the manufacturer expects to be able to sell (which then determines how they divide up that THX fee and add it to the sticker price).

As Iggy aptly puts it, one of the significant "value added" aspects of a THX logo is consumer confidence or comfort. The thing that I give THX the most credit for is helping the industry as a whole by guiding designers and consumers to look at issues like bass management and helping to come up with better solutions. They've even done some simple things like developing a separate color code for multichannel analog audio inputs and outputs (rather than the three or four pairs of red and white jacks), a system that I seem to recall seeing on some non-THX equipment in the last year or so. The point that I feel is probably most important to take away from a discussion of THX is a simple one: the THX logo shows up on some very nice gear, but if you are shopping for a piece of home theater equipment it is important to allow non-THX equipment onto your list as well because there is some very good non-THX gear on the market that should not be overlooked.