You are correct about the intake.
Here's a brief explanation of tunes (full credit to Jack):
1. Stock tune: You go to a department store and buy a suit of clothes (ready to wear). Your girlfriend yawns.
2. Canned tunes: You have the suit you bought tailored at one of the combination cleaner/tailoring places, so that it fits you like a glove. Your girlfriend tells you she likes the way you look and seems really happy to be with you.
3. Custom tunes: You pay to have a big name designer create a suit of clothes for you out of fabrics fit for a king. You ditch your girlfriend and accompany a Hollywood starlet to the Academy Awards.
A full explanation is here:
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