American English AmE, ae, AmEng, useng

0:01
[ˈmaʊnʔn̩]
partner (glottalized t) (0:01)
0:02
[ˈpʰɑɹʔnɚ]
leader (d-flapping) (0:01)
0:01
[ˈɫiɾɚ]
cattle (t-flapping) (0:01)
0:01
[ˈkʰæɾɫ̩]
party (t-flapping) (0:01)
0:01
[ˈpʰɑɹɾi]

Optional flapping in certain contexts relatively without flapping (0:01) 0:02 [ˈɹɛɫɨtʰɪvɫi] relatively with optional flapping (0:01) 0:02 [ˈɹɛɫɨɾɪvɫi]

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  T-glottalization: /t/ is normally pronounced as a glottal stop [ʔ] when both after a vowel or a liquid and before a syllabic [n̩] or any non-syllabic consonant, as in button [ˈbʌʔn̩] ( listen) or fruitcake [ˈfɹuʔkʰeɪk] ( listen). In absolute final position after a vowel or liquid, /t/ is also replaced by, or simultaneously articulated with, glottal constriction:^[47] thus, what [wʌʔ] or fruit [fɹuʔ]. (This innovation of /t/ glottal stopping may occur in British English as well and variably between vowels.)
  
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  Flapping: /t/ or /d/ becomes a flap [ɾ] ( listen) both after a vowel or /r/ and before an unstressed vowel or a syllabic consonant other than [n̩], including water [ˈwɔɾɚ] ( listen), party [ˈpʰɑɹɾi] and model [ˈmɑɾɫ̩]. This results in pairs such as ladder/latter, metal/medal, and coating/coding being pronounced the same. Flapping of /t/ or /d/ before a full stressed vowel is also possible but only if that vowel begins a new word or morpheme, as in what is it? [wʌɾˈɪzɨʔ] and twice in not at all [nɑɾɨɾˈɔɫ]. Other rules apply to flapping to such a complex degree in fact that flapping has been analyzed as being required in certain contexts, prohibited in others, and optional in still others.^[48] For instance, flapping is prohibited in words like seduce [sɨˈdus], retail [ˈɹitʰeɪɫ], and monotone [ˈmɑnɨtʰoʊn], yet optional in impotence [ˈɪmpɨɾɨns, ˈɪmpɨtʰɨns].
  
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  Both intervocalic /nt/ and /n/ may commonly be realized as [ɾ̃] (a nasalized alveolar flap) (flapping) or simply [n], making winter and winner homophones in fast or informal speech.
  
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  L-velarization: England's typical distinction between a "clear L" (i.e. [l] ( listen)) and a "dark L" (i.e. [ɫ] ( listen)) is much less noticeable in nearly all dialects of American English; it is often altogether absent,^[49] with all "L" sounds tending to be "dark," meaning having some degree of velarization,^[50] perhaps even as dark as [ʟ] ( listen) (though in initial position, perhaps less dark than elsewhere among some speakers).^[51] The only notable exceptions to this velarization are in some Spanish-influenced American English varieties (such as East Coast Latino English, which typically shows a clear "L" in syllable onsets) and in older, moribund Southern speech, where "L" is clear in an intervocalic environment between front vowels.^[52]
  
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  Weak vowel merger: The vowel /ɪ/ in unstressed syllables generally merges with /ə/ and so effect is pronounced like affect, and abbot and rabbit rhyme. The quality of the merged vowel varies considerably based on environment but is typically more open, like [ə], in word-initial or word-final position, but more close, like [ɪ~ɨ], elsewhere.^[53]
  
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  Raising of pre-voiceless /aɪ/: Many speakers split the sound /aɪ/ based on whether it occurs before a voiceless consonant and so in rider, it is pronounced [äɪ], but in writer, it is raised to [ʌɪ] (because [t] is a voiceless consonant while [d] is not). Thus, words like bright, hike, price, wipe, etc. with a following voiceless consonant (such as /t, k, θ, s/) use a more raised vowel sound compared to bride, high, prize, wide, etc. Because of this sound change, the words rider and writer ( listen), for instance, remain distinct from one another by virtue of their difference in height (and length) of the diphthong's starting point (unrelated to both the letters d and t being pronounced in these words as alveolar flaps [ɾ]). The sound-change also applies across word boundaries, though the position of a word or phrase's stress may prevent the raising from taking place. For instance, a high school in the sense of "secondary school" is generally pronounced [ˈhɐɪskuɫ]; however, a high school in the literal sense of "a tall school" would be pronounced [ˌhaɪˈskuɫ]. The sound change began in the Northern, New England, and Mid-Atlantic regions of the country,^[54] and is becoming more common across the nation.
  
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  Many speakers in the Inland North, Upper Midwestern, and Philadelphia dialect areas raise /aɪ/ before voiced consonants in certain words as well, particularly [d], [g] and [n]. Hence, words like tiny, spider, cider, tiger, dinosaur, beside, idle (but sometimes not idol), and fire may contain a raised nucleus. The use of [ʌɪ], rather than [aɪ], in such words is unpredictable from phonetic environment alone, but it may have to do with their acoustic similarity to other words that with [ʌɪ] before a voiceless consonant, per the traditional Canadian-raising system. Some researchers have argued that there has been a phonemic split in those dialects, and the distribution of the two sounds is becoming more unpredictable among younger speakers.^[55]
  
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  Conditioned /æ/ raising (especially before /n/ and /m/): The raising of the /æ/ or TRAP vowel occurs in specific environments that vary widely from region to region but most commonly before /n/ and /m/. With most American speakers for whom the phoneme /æ/ operates under a somewhat-continuous system, /æ/ has both a tense and a lax allophone (with a kind of "continuum" of possible sounds between both extremes, rather than a definitive split). In those accents, /æ/ is overall realized before nasal stops as more tense (approximately [eə̯]), while other environments are more lax (approximately the standard [æ]); for example, note the vowel sound in [mæs] for mass, but [meə̯n] for man). In the following audio clip, the first pronunciation is the tensed one for the word camp, much more common in American English than the second ( listen).
  
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    In some American accents, however, specifically those from Baltimore, Philadelphia, and New York City, [æ] and [eə̯] are indeed entirely-separate (or "split") phonemes, for example, in planet [pʰlænɨʔ] vs. plan it [pʰleənɨʔ]. They are called Mid-Atlantic split-a systems. The vowels move in the opposite direction (high and forward) in the mouth compared to the backed Standard British "broad a", but both a systems are probably related phonologically, if not phonetically, since a British-like phenomenon occurs among some older speakers of the eastern New England (Boston) area for whom /æ/ changes to /a/ before /f/, /s/, /θ/, /ð/, /z/, /v/ alone or when preceded by a homorganic nasal.