Editing Japanese pitch accent (section)

===Binary pitch===
The foregoing describes the actual pitch. In most guides, however, accent is presented with a two-pitch-level model. In this representation, each mora is either high (H) or low (L) in pitch, with the shift from high to low of an accented mora transcribed HꜜL. 
# If the accent is on the first mora, then the first syllable is high-pitched and the others are low: HꜜL, HꜜL-L, HꜜL-L-L, HꜜL-L-L-L, ''etc.''
# If the accent is on a mora other than the first, then the first mora is low, the following morae up to and including the accented one are high, and the rest are low: L-Hꜜ, L-HꜜL, L-H-HꜜL, L-H-H-HꜜL, ''etc.''
# If the word is ''heiban'' (accentless), the first mora is low and the others are high: L-H, L-H-H, L-H-H-H, L-H-H-H-H, ''etc.'' This high pitch spreads to unaccented [[Japanese particles|grammatical particles]] that attach to the end of the word, whereas these would have a low pitch when attached to an accented word (including one accented on the final mora).

Phonetically, although only the terms "high" and "low" are used, the "high" of an unaccented mora is not as high as an accented mora. Different analyses may treat final-accented (''odaka'') words and unaccented (''heiban'') words as identical and only distinguishable by a following particle, or phonetically contrastive and potentially phonemic based on how high a "high" tone actually is (see the Tertiary pitch subsection below). And the phonetic tones are never truly stable, but degrade toward the end of an utterance. This is especially noticeable in longer words, where the so-called "high" pitch tapers off toward the end. This tapering is especially exemplified by what is variously known as ''downstep''{{efn|The overall lowering of pitch after an accent drop. Not to be confused with the accent drop itself, which is indicated by the downward arrow and which is called "downstep" elsewhere in this article.|name=truedownstep}}, ''downdrift'' or ''catathesis'', where the "high" pitch of words becomes successively lower after each accented mora:<ref name=haraguchi>{{cite book|last1=Haraguchi|first1=Shosuke|title=The Tone Pattern of Japanese: An Autosegmental Theory of Tonology|date=1979|publisher=Linguistic Society of America}}</ref><ref name=poser>{{cite book|last1=Poser|first1=William|title=The Phonetics and Phonology of Tone and Intonation in Japanese|date=1985|publisher=Massachusetts Institute of Technology|location=Massachusetts}}</ref><ref name=vance/>

{| class="wikitable" style="text-align:center; margin:1em auto 1em auto"
! Phrase
! Phonemic accent pattern
|-
|海で泳ぎ (''umi-de oyogi'' "swimming in the sea")
|HꜜL-L L-HꜜL
|-
|被ってみたら (''kabutte mitara'' "try putting on the head")
|L-HꜜL-L HꜜL-L
|}

In slow and deliberate enunciation (for example, with a pause between elements), the "high" tone of the second element in these phrases could still be sufficiently "high," but in natural, often pauseless, speech, it could become as low as the "low" tone of the first element, since there is an accented mora in that first element.

====Tertiary pitch====
Earlier phonologists made use of a three-tone system, with an additional "mid" tone (M).<ref name=poser /> For example, 端 (''hashi'' "edge", ''heiban''/unaccented) is considered to have a L-M pattern, while 橋 (''hashi'' "bridge", ''odaka''/final-accented) is to have a L-H pattern. This contrast is supported by phonetic analyses, which show that the contrast in frequency between the "low" and "high" tones in, for example, 花 (''hana'' "flower", ''odaka''/final-accented), is much starker than the contrast between the "low" and "mid" tones in 鼻 (''hana'' "nose", ''heiban''/unaccented).{{sfnp|Labrune|2012|p=182}} Moreover, the "high" tone in final-accented words is phonetically higher than the "mid" tone in unaccented words. With respect to potential minimal pairs such as "edge" ''hashi'' vs "bridge" ''hashi'' and "nose" ''hana'' vs "flower" ''hana'', the "mid" tone, in theory, should be considered phonemic, but it is now largely merged with the "high" tone<ref name=poser /> as phonologists claim there are no perceptible differences in pitch pattern between a final-accented word (''odaka'') without a following particle and an unaccented word (''heiban''):
{| class="wikitable" style="text-align:center; margin:1em auto 1em auto"
! Word
! Old analysis<ref name=sakuma>{{cite book|last1=Sakuma|first1=Kanae|title=国語の発音とアクセント|date=1919|publisher=同文館|location=Tokyo}}</ref>
! New analysis<ref name=poser />
|-
|端 (''hashi'' "edge")
|L-M
|L-H
|-
|橋 (''hashi'' "bridge")
| colspan=2 |L-Hꜜ
|}

The "mid" tone also corresponds to what is now considered the "low" tone in initial-accented (''atamadaka'') and medial-accented (''nakadaka'') words:
{| class="wikitable" style="text-align:center; margin:1em auto 1em auto"
! Word
! Old analysis<ref name=sakuma />
! New analysis<ref name=poser />
|-
|火鉢 (''[[hibachi]]'')
|HꜜM-M
|HꜜL-L
|-
|お玉 (''otama'' "ball")
|L-HꜜM
|L-HꜜL
|}