审阅范围 · Review scope
限定范围独立审阅。请保留正文中的出处与限制；不代表全库最终验收、实际演奏或学习效果验证。
Independent review within the stated scope. Keep the evidence and limitations stated in the text in view. This is not final corpus acceptance or validation of performance or learning outcomes.
本页保留作者送审冻结字节，因此正文或数据可能仍有“候选／等待审阅／未发布”标记。当前版本已通过限定独立复核并发布；旧标记只记录冻结时状态。通过范围是双语含义、限定来源文字／静帧及原创固定例题检查，不含原声听校、连续动作、完整源谱、实际演奏、身体适用性或学习效果验证。
This page preserves the author’s frozen review bytes, so prose or data may still contain candidate, pending-review or unpublished labels. This version has passed bounded independent review and repository publication; those labels record author-time status only. Acceptance covers bilingual meaning, bounded source text/stills and original fixed-fixture checks, not source audition, continuous motion, full source scores, actual performance, physical suitability or learning outcomes.
十二小节地图：和弦变化与下一轮边界
十二小节，不是十二次换和弦
看见连续四格F7时，你走过了四小节，但格与格之间没有换和弦。这个差别是本课的起点：分别数小节、标签位置、不同和弦种类及相邻标签的改变。先预测：十二小节只用F7、Bb7、C7，是否必须换十二次和弦？写下答案或“不确定”，再读地图。
本课明确设定F为蓝调中心，比较两个原创纸面地图A与T；每轮均为十二小节4/4。它们是给定练习，不是所有蓝调的唯一形式。这里的chorus指完整走过一轮和声形式，不是必然指流行歌曲的“副歌”，也不要求每轮旋律相同。
需要认识字母音名、升降号、4/4与四分音符单位；相关入口在文末。C4是中央C，尾数是八度编号。本课可用纸笔完成，不依赖听出和弦，也不要求同时弹四音。已有D蓝调练习卡处理提早四级与实际和弦起放；本课另练标签计数与双轮边界。
先固定I7、IV7、V7各指什么
本课标号约定为I7＝F7、IV7＝Bb7、V7＝C7。罗马数字从给定中心F标根音级数；7在这三个代号中表示大三和弦加根音上方小七度。下表按根音、三音、五音、七音写全，半音位移均为0、4、7、10。
F7的七音是Eb，不是E；Bb7的七音是Ab，不是A；C7的七音是Bb，不是B。换成后三个还原音会得到相应的大七和弦，不能当成相同代号的随意拼写。表内音区只是分析样本，不是规定的伴奏排列、手跨度或指法。
三者都有属七和弦的结构，但本地图只有C根音标V。F7在给定F蓝调中心下标I7，Bb7标IV7；不能见到7就把每个和弦都当五级，或把F7→Bb7→C7解释成每换一个根音就换一次调。给定中心与实际作品中如何建立中心，也要分开。
可选键盘核对只用于找音名：按表找出各行四个键，必要时一次核对一个音；这个找键步骤不设拍速或演奏时值，听感可另记。按十二平均律，半音数可由两音MIDI编号相减；本表的MIDI只是可复算的音高坐标，不是指法。主任务仍是下面的纸面地图。
| 级数 | 代号 | 分析音名 | MIDI编号 | 相对根音半音 |
|---|---|---|---|---|
| I7 | F7 | F4 A4 C5 Eb5 | 65 69 72 75 | 0 4 7 10 |
| IV7 | Bb7 | Bb3 D4 F4 Ab4 | 58 62 65 68 | 0 4 7 10 |
| V7 | C7 | C4 E4 G4 Bb4 | 60 64 67 70 | 0 4 7 10 |
两个完整地图：只改变第十二小节
q表示四分音符单位，单轮全局时间从q=0开始；每格4q，第十二小节结束于q=48。[a,b)包含a、不含b。地图只指定各区间的和弦标签，没有指定任何琴键何时起音、放开或休止；四拍F7不等于已写一个四拍四音和弦，也不等于四次起音。
A版第11、12小节都为I7。T版只将第12小节改成V7，作为本练习通往下一轮I7的简化回转选择；turnaround在这里指末段引回下一轮的安排，不是要求所有回转都只用一个V7。两版的第2小节都仍为I7。
可把1–4、5–8、9–12看作三个四小节区块来定位；视觉分组不增加小节或时间。早到IV、每小节多次换和弦、其他末段安排等都需要另给完整地图；不要悄悄套进本例，再沿用本例的计数答案。
| 小节 | q区间 | A代号 | A级数 | T代号 | T级数 |
|---|---|---|---|---|---|
| 1 | [0,4) | F7 | I7 | F7 | I7 |
| 2 | [4,8) | F7 | I7 | F7 | I7 |
| 3 | [8,12) | F7 | I7 | F7 | I7 |
| 4 | [12,16) | F7 | I7 | F7 | I7 |
| 5 | [16,20) | Bb7 | IV7 | Bb7 | IV7 |
| 6 | [20,24) | Bb7 | IV7 | Bb7 | IV7 |
| 7 | [24,28) | F7 | I7 | F7 | I7 |
| 8 | [28,32) | F7 | I7 | F7 | I7 |
| 9 | [32,36) | C7 | V7 | C7 | V7 |
| 10 | [36,40) | Bb7 | IV7 | Bb7 | IV7 |
| 11 | [40,44) | F7 | I7 | F7 | I7 |
| 12 | [44,48) | F7 | I7 | C7 | V7 |
同一组标签，几个不同计数
一轮有12个小节，也有12个逐小节标签位置；不同代号只有F7、Bb7、C7三种。“变化”只在相邻小节标签不同时记1次。起点F7是建立首个标签，本身不算从一个已知前和弦换来的变化；本表没有给前奏和弦。
A的变化发生在进入第5、7、9、10、11小节时，共5次；T还在进入第12小节时再变一次，共6次。A连续同标签区段为F7×4、Bb7×2、F7×2、C7×1、Bb7×1、F7×2，所以有6段；T最后两小节拆为F7与C7，成为7段。
同标签区段是和声标记的压缩表示，不是要求把声音一直连住。例如A的第1–4小节可以在纸面合记为F7的[0,16)区间，但具体伴奏仍可能有很多起音或休止。没有演奏事件表时，起音数与休止数是未指定，不应填0或12冒充已知。
| 版本 | 小节／标签数 | 不同代号数 | 内部变化数 | 变化进入的小节 | 连续同标签段数 |
|---|---|---|---|---|---|
| A | 12 / 12 | 3 | 5 | 5 7 9 10 11 | 6 |
| T | 12 / 12 | 3 | 6 | 5 7 9 10 11 12 | 7 |
跨轮时同时保留两种小节坐标
本课的双轮路线只连接两份给定地图，没有前奏、弱起、间奏、延长或尾声。第一轮占q=0到48，第二轮占q=48到96；第二轮每格的起终点等于单轮表加48。跨到q=48后，轮内小节回到1；连续总小节则是13。它是第二轮第1小节，不是第一轮多出的第13小节。
边界是否换和弦，要比较第一轮最后标签与第二轮第一个标签。A接A时F7→F7，边界不变；T接T时C7→F7，边界变1次。双A的总变化是5+0+5＝10；双T是6+1+6＝13。中间的1来自边界，不能漏掉，也不能每一轮都多算一次起点。
A接T与T接A也能逐格定义。A接T的边界仍是F7→F7，总计11；T接A的边界是C7→F7，总计12。四条路线都各有24小节、96q与3种代号。这里的“13次变化”不是“13种和弦”，也不是多出来的小节。
若为指格练习加均匀时钟，四分音符60 BPM时一轮48秒、双轮96秒；48 BPM时分别60秒与120秒。纸面也可不计时。这些是给定拍速下的地图长度，不是原课录音的速度、实际演奏时长或对学习者的速度要求。
| 双轮路线 | 第一轮内部 | 边界 | 第二轮内部 | 总变化 | 小节／q |
|---|---|---|---|---|---|
| AA | 5 | 0 | 5 | 10 | 24 / 96 |
| AT | 5 | 0 | 6 | 11 | 24 / 96 |
| TA | 6 | 1 | 5 | 12 | 24 / 96 |
| TT | 6 | 1 | 6 | 13 | 24 / 96 |
纸面实验：先预测，再核对边界
先抄一份只有小节号与q区间的空表，遮住地图和计数答案。根据已学A版填满12格；在每一对相邻格之间画“相同”或“改变”，再统计。把原答保留下来后才对照，分别记录漏格、标签错误、把起点误算变化或把重复标签误算变化。
接着从A只改第12格成为T，先预测哪些计数改变。小节数、总q与和弦种类数不变；单轮变化与连续同标签段各多1。再把T抄两轮：每格都写“轮号:轮内小节”，第二轮同时写连续总小节13–24，检查边界C7→F7。
若边界混淆，局部只取第一轮第11、12小节与第二轮第1、2小节，共16q。下面同时列出全局和本地时钟；本地0对应全局40，本地8才进入第二轮。局部T标签是F7、C7、F7、F7，有2次变化；这不是整个双T路线的13次变化。
局部检查后回到双T全部24格，从q=0走到96；不省略第一轮前10格，也不在第二轮第2格结束。指格时可以口数每格1、2、3、4；进入下一格再读标签。指到新格是一次导航动作，不自动算换和弦或音乐起音。
| 连续小节 | 轮号:小节 | 全局q | 本地q | AA标签 | TT标签 |
|---|---|---|---|---|---|
| 11 | 1:11 | [40,44) | [0,4) | F7 | F7 |
| 12 | 1:12 | [44,48) | [4,8) | F7 | C7 |
| 13 | 2:1 | [48,52) | [8,12) | F7 | F7 |
| 14 | 2:2 | [52,56) | [12,16) | F7 | F7 |
记录错误类型，延后复测同一地图
空白记录包含：地图路线、是否遮答案、提示、原答的小节／标签／种类／变化／区段计数、边界坐标、完整双轮结果、下一步和复测计划。若用了时钟，另写实际拍速与拍单位。没有实际音符演奏数据时，把起音与休止栏保留为“未指定”，不要把指格次数填进去。
若只错拼写，回查F7、Bb7、C7的七音再恢复整张地图；若标签对、变化数错，重新检查相邻关系与q=48边界；若漏小节，先核24格与两套坐标。一次处理一类错误，再返回完整双T路线，不能只凭四格局部成功就记“全段完成”。
计划在下一次练习开始、重新看答案前复测熟悉的同一双T地图；保留同样的提示条件，若计时则用同一拍速。先重建24格与变化标记，后核对，并记真实间隔。即时纠正与延后保留分别登记；本页没有真实学习者结果，也没有因此证明听辨、蓝调风格或长期学习效果。
来源边界与已有练习的关系
NC-007的100段既有ASR已全读，另检查55、110、170、220、290秒五张静帧。55秒只见前两行共8个和弦标签；110秒见C7、F7、G7；170秒见omit 5标记；220秒见框出的上声部布局及连接描述；290秒见三行谱表与C9／F13／G13类标签。这里只确认可见标签和布局，不逐音验收源谱，也不由静帧断言声响顺畅。
转写把十二小节形式与三种和弦联系，并提到其他变化；归属仍是未经原声听校的ASR候选。重复和弦口述及音名存在明显机器识别问题，所以本课没有拿转写重建来源的逐拍和声或配音；后段的听感、扩展音与walking bass也不纳入本课演奏验收。
F中心的A／T地图、四种双轮组合、计数诊断与边界局部均为本库原创，未复制源谱。既有十二格练习卡数据中的PUB18-e8812fb391c3使用D中心、提早IV与实际音符／休止，本课不将它改名或重复计为新卡；本批新增练习卡与公开文章审阅数均为0。
前置与延伸：音程拼写、和弦身份与配置、节奏、保留与迁移、本课来源记录。四文件为待独立审阅候选；作者基线仍为93/399的有限ASR文字／选帧范围。未验完整视听、连续动作、实际演奏或学习效果；本稿没有发布增量。
起音与休止次数未指定；和弦标签不是音符事件。
A twelve-bar map: chord changes and the next chorus boundary
Twelve bars do not mean twelve chord changes
Four consecutive F7 boxes occupy four bars, but the boundaries between them contain no chord change. That distinction starts this lesson: count bars, label positions, distinct chord identities and changes between adjacent labels separately. First predict: must twelve bars using only F7, Bb7 and C7 contain twelve chord changes? Write an answer or “uncertain” before reading the map.
This lesson stipulates F as a blues center and compares two original paper maps, A and T; each chorus is twelve bars of 4/4. They are specified exercises, not the sole form of all blues. Here “chorus” means one complete pass through the harmonic form, not necessarily a pop-song refrain, and it does not require the same melody in every pass.
You need letter names, accidentals, 4/4 and the quarter-note unit; prerequisites are linked below. C4 is middle C and the final numeral is an octave number. This lesson can be completed on paper without recognizing chords by ear or pressing four notes together. An existing D-blues card covers early IV and actual chord attacks/releases; this lesson instead practices label counts and the boundary between two choruses.
Fix the meanings of I7, IV7 and V7 first
Our notation convention is I7 = F7, IV7 = Bb7 and V7 = C7. The Roman numerals locate chord roots relative to the stipulated center F; 7 in these three symbols means a major triad plus a minor seventh above its root. The table spells root, third, fifth and seventh in full, with semitone offsets 0,4,7,10 in every row.
The seventh of F7 is Eb rather than E; that of Bb7 is Ab rather than A, and that of C7 is Bb rather than B. Using those natural alternatives would produce the corresponding major-seventh chords, not interchangeable spellings of the same symbols. The registers in the table are analytical specimens, not prescribed accompaniment voicings, hand spans or fingerings.
All three have dominant-seventh structure, but only the C-rooted chord is labeled V in this map. F7 is I7 and Bb7 is IV7 relative to the stipulated F-blues center. A 7 does not make every chord V, nor does F7→Bb7→C7 imply a key change at every new root. A stipulated center is also distinct from demonstrating how an actual piece establishes a center.
An optional keyboard check only locates the written notes: find each row’s four keys, checking one note at a time if useful; this locating step has no prescribed tempo or performance durations, and listening impressions can be recorded separately. In twelve-tone equal temperament, subtracting MIDI pitch numbers gives semitone distance. MIDI numbers here are reproducible pitch coordinates, not fingerings. The main task remains the paper map below.
| Degree | Symbol | Analytical pitches | MIDI numbers | Semitones above root |
|---|---|---|---|---|
| I7 | F7 | F4 A4 C5 Eb5 | 65 69 72 75 | 0 4 7 10 |
| IV7 | Bb7 | Bb3 D4 F4 Ab4 | 58 62 65 68 | 0 4 7 10 |
| V7 | C7 | C4 E4 G4 Bb4 | 60 64 67 70 | 0 4 7 10 |
Two complete maps: change only bar twelve
q denotes a quarter-note unit, with one chorus starting at q=0. Every box spans 4q and bar twelve ends at q=48. [a,b) includes a and excludes b. The map assigns chord labels to intervals but does not specify key attacks, releases or rests. Four beats labeled F7 are neither a written four-beat four-note chord nor four attacks.
Version A uses I7 in both bars 11 and 12. Version T changes only bar 12 to V7 as a simplified turnaround choice leading to the next chorus’s I7. Here “turnaround” means an ending passage arranged to lead back into the next pass, not a requirement that every turnaround contain only one V7. Bar 2 remains I7 in both versions.
Grouping bars 1–4, 5–8 and 9–12 into three four-bar blocks helps navigation; visual grouping adds neither a bar nor time. Early IV, several chord changes within a bar, and other endings require their own complete maps. Do not silently insert them into this example while retaining its counting answers.
| Bar | q interval | A symbol | A degree | T symbol | T degree |
|---|---|---|---|---|---|
| 1 | [0,4) | F7 | I7 | F7 | I7 |
| 2 | [4,8) | F7 | I7 | F7 | I7 |
| 3 | [8,12) | F7 | I7 | F7 | I7 |
| 4 | [12,16) | F7 | I7 | F7 | I7 |
| 5 | [16,20) | Bb7 | IV7 | Bb7 | IV7 |
| 6 | [20,24) | Bb7 | IV7 | Bb7 | IV7 |
| 7 | [24,28) | F7 | I7 | F7 | I7 |
| 8 | [28,32) | F7 | I7 | F7 | I7 |
| 9 | [32,36) | C7 | V7 | C7 | V7 |
| 10 | [36,40) | Bb7 | IV7 | Bb7 | IV7 |
| 11 | [40,44) | F7 | I7 | F7 | I7 |
| 12 | [44,48) | F7 | I7 | C7 | V7 |
Different counts from the same labels
One chorus has 12 bars and 12 bar-label positions, but only three distinct symbols: F7, Bb7 and C7. Count one “change” only when neighboring bars have different labels. The initial F7 establishes the first label; it is not a change from a known preceding chord, because no introduction chord is supplied.
A changes when entering bars 5,7,9,10 and 11, for five changes. T also changes on entering bar 12, for six. A’s runs of identical labels are F7×4, Bb7×2, F7×2, C7×1, Bb7×1 and F7×2, making six runs. T splits the last two bars into F7 and C7, making seven runs.
A run compresses harmonic labels; it does not require a continuously held sound. For example, A’s bars 1–4 can be represented as F7 over [0,16), while an actual accompaniment could contain many attacks or rests. Without a performance-event table, attack and rest counts are unspecified; neither 0 nor 12 should be entered as if known.
| Version | Bars / labels | Distinct symbols | Internal changes | Bars entered with change | Identical-label runs |
|---|---|---|---|---|---|
| A | 12 / 12 | 3 | 5 | 5 7 9 10 11 | 6 |
| T | 12 / 12 | 3 | 6 | 5 7 9 10 11 12 | 7 |
Keep both bar coordinates at a chorus boundary
The two-chorus route joins two copies of the stipulated maps with no introduction, pickup, interlude, extension or coda. Chorus 1 occupies q=0–48 and chorus 2 q=48–96; add 48 to each one-chorus start/end for the second copy. At q=48, the within-chorus bar resets to 1 while the continuous bar number is 13. It is chorus 2 bar 1, not an extra thirteenth bar in chorus 1.
Whether the boundary changes harmony depends on the last label of chorus 1 and the first of chorus 2. A→A gives F7→F7, with no boundary change; T→T gives C7→F7, adding one. Two A choruses total 5+0+5 = 10 changes; two T choruses total 6+1+6 = 13. The middle 1 is the boundary change: do not omit it or add an extra initial change to every chorus.
A→T and T→A are equally explicit bar-by-bar routes. A→T still crosses F7→F7 and totals 11 changes; T→A crosses C7→F7 and totals 12. All four routes contain 24 bars, 96q and three distinct symbols. “Thirteen changes” means neither “thirteen kinds of chord” nor extra bars.
If a steady clock is added for pointing through the boxes, quarter note = 60 BPM gives 48 seconds per chorus and 96 for two; at 48 BPM the durations are 60 and 120 seconds. Paper work may also be untimed. These are map lengths at specified tempos, not the source recording’s tempo, measured performance durations or speed requirements.
| Two-chorus route | Within first | Boundary | Within second | Total changes | Bars / q |
|---|---|---|---|---|---|
| AA | 5 | 0 | 5 | 10 | 24 / 96 |
| AT | 5 | 0 | 6 | 11 | 24 / 96 |
| TA | 6 | 1 | 5 | 12 | 24 / 96 |
| TT | 6 | 1 | 6 | 13 | 24 / 96 |
Paper experiment: predict, then check the boundary
Copy a blank table containing only bar numbers and q intervals, then cover the map and counting answers. Reconstruct all 12 boxes of the familiar A map, marking each adjacent pair “same” or “changed” before totaling. Retain the original answer before checking; distinguish omitted boxes, wrong labels, counting the initial label as a change, and counting repeated labels as changes.
Next change only A’s twelfth box to create T, predicting which counts change. Bars, total q and distinct chord identities stay the same; the single-chorus change count and run count each increase by one. Then copy T twice, giving every box a “chorus:bar” coordinate and also labeling the second chorus with continuous bars 13–24. Check the C7→F7 boundary.
If the boundary is confusing, isolate chorus 1 bars 11–12 and chorus 2 bars 1–2, totaling 16q. The table gives both global and local clocks: local 0 corresponds to global 40, and local 8 starts chorus 2. The local T labels are F7,C7,F7,F7 with two changes; that is not the full T→T route’s thirteen changes.
After the local check, restore all 24 boxes of T→T from q=0 to 96. Retain the first ten bars and continue past chorus 2 bar 2. You may count 1,2,3,4 in each box and read the next label when entering the next box. Moving a pointer to a new box is a navigation action, not automatically a chord change or musical attack.
| Continuous bar | Chorus:bar | Global q | Local q | AA label | TT label |
|---|---|---|---|---|---|
| 11 | 1:11 | [40,44) | [0,4) | F7 | F7 |
| 12 | 1:12 | [44,48) | [4,8) | F7 | C7 |
| 13 | 2:1 | [48,52) | [8,12) | F7 | F7 |
| 14 | 2:2 | [52,56) | [12,16) | F7 | F7 |
Record the error type and retest the same map later
A blank record includes route, whether answers were hidden, cues, original counts of bars/labels/identities/changes/runs, boundary coordinates, the complete two-chorus result, next step and retest plan. If a clock was used, separately record the actual tempo and beat unit. With no actual note-performance data, retain “unspecified” for attacks and rests rather than filling in pointer movements.
If only spelling is wrong, check the sevenths of F7, Bb7 and C7, then restore the full map. If labels are right but the change count is wrong, inspect adjacency and the q=48 boundary. If bars are missing, check all 24 boxes and both coordinate systems first. Address one error type at a time and return to complete T→T; a successful four-box excerpt is not completion of the full route.
Plan a retest of the same familiar T→T map at the start of the next session before rereading answers. Keep the same cue conditions and, if timed, the same tempo. Reconstruct all 24 boxes and change marks before checking, and record the actual delay. Record immediate correction separately from delayed retention; this page contains no actual learner results and establishes no aural, blues-style or long-term learning effect.
Source limits and relation to the existing exercise
All 100 existing NC-007 ASR segments were read, with five stills at 55,110,170,220 and 290 seconds. The 55-second image shows only the first two rows, totaling eight chord labels; 110 shows C7,F7,G7; 170 shows omit 5 markings; 220 shows boxed upper-part layouts and a connection description; 290 shows three score systems with C9/F13/G13-type labels. This confirms visible labels and layouts only, not every source-score note or an audibly smooth connection.
The transcript connects a twelve-bar form with three chords and mentions other variants; those attributions remain ASR candidates unaudited against the original audio. Repeated spoken chords and note names contain conspicuous recognition problems, so this lesson does not reconstruct the source’s beat-by-beat harmony or voicing from ASR. Later discussion of perceived sound, extensions and walking bass is not accepted as performance evidence here.
The F-centered A/T maps, four two-chorus combinations, counting diagnosis and boundary excerpt are original and do not copy the source score. Existing twelve-box card data, PUB18-e8812fb391c3, uses a D center, early IV and actual notes/rests. This lesson neither renames it nor counts it again as a new card; this batch adds zero practice cards and zero public-article reviews.
Prerequisites and next reading: interval spelling, chord identity and voicing, rhythm, retention and transfer, and this lesson’s source record. These four files await independent review; the author baseline remains 93/399 for limited ASR text/selected-still scope. Full audiovisual content, continuous motion, actual performance and learning effects are unverified; this draft adds no published coverage.
Attack and rest counts are unspecified; chord labels are not note events.