I thought I could comment a bit more here, since I didn't want to run away with Smithy's topic any more than I did already.
I get it now. I'm not familiar with linguistic lingo, so I can't put a finger on it, but I can tell there is a sort of difference between the two that I don't think I make when I say them (lap and lamp). Or perhaps I do, like you said, but the difference is very subtle and so I don't notice it, not having a sharp eye for it (or ear)
Anyway, language is always something I have been interested in, but never got around to. Thus I am befuddled when I do things like try to research speaking old english, and they talk about voiced velar spirants, which blows my mind away. What does that mean?
I would put a clip up if it interests you, though you probably know plenty already of the midwestern accent and need no further case studies- i'm not quite sure how recording works, yet, but I could investigate that, or Skype if you'd like. Heck, I just got Skype and a webcam from the lady so I'd Skype with anyone here that wants to chat, just because it is new and cool to me.
Oh, and Alex, if you're reading, I thought of someone who definitely has a more pronounced "#1" on the list- Dustin's mom. She always makes that sound when saying something like "that". It's not super pronounced, but it's definitely enough that I can catch it.
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Honestly a lot of it is just knowing what the terms mean! Once you do, voiced (vocal chords vibrating) velar (back of the tongue touching the velum, or soft palate) spirant (sound made by airflow through a narrow passageway) makes perfect sense.
And it comes with experience, too. Like learning to read a new alphabet, before you do, there's no way you can look at it and make any sense of it, but after you do, there's no way not to. Similarly, before I learned phonetics I never noticed I said "marry" differently from all of my grade school friends in Georgia, but now (and this is kind of annoying) I can't listen to a single person speak without analyzing their phonetic patterns at all times.
Don't think Skype is necessary, just put up a recording if you have a mic (better yet, I did it from my iPhone using the built-in Voice Memos to record and CloudApp to host, though Dropbox should work too). Do your pronunciations of "lap" and "lamp" seem to deviate significantly from mine?
Love this stuff. :)
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Seth: What are you making?
Evan: I'm just drilling holes. Last two weeks, **** it.
Well Mark she's from Texas, isn't she? I think it's a leftover from there rather than a participation in the NCVS (which by the way I was JUST reading about like two weeks ago and thinking was really interesting).