I just tried an Imperial IPA I brewed, specifically a dogfish head 90min IPA clone. I used amarillo, warrior, and simcoe hops. The beer is a bit young (just a week in the bottle) so it's still a tad bit undercarbonated, but tastes pretty good. I fermented it for a week, and left it in the secondary (and dry hopped) for 4 more weeks and now it's been bottled for a little over a week.
I compared it with a Dogfish Head Squall IPA (similar to the 90min but unfiltered) and it was pretty close except my beer had a distinct butter aroma. I'm not sure it is diacetyl or not. It smelled kind of like an artificial maple syrup aroma. Like a McDonalds hotcake or a IHOP pancake with butter. Basically, an artificial butter pancake syrupy aroma. It's not bad, it's just unusual, and not present in the dogfish head, which has a fresh herbal and flowery hop aroma. I'm wondering what causes the cheap pancake aroma and whether it will go away with aging, or what I can do to prevent it in the future.
PS The beer is 9% ABV and since I had to drink two of them (the homebrew plus the commercial comparison), I apologize for any typos in this post in advance.