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datasets/melodies/pop/train/sad/README.md

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+# Pop Sad Melodies - Training Set
+
+This directory contains emotional/melancholic pop melodies for training.
+
+## Directory Structure
+- README.md (this file)
+- pop_train_sad_directory.json (directory metadata)
+- MIDI files and their corresponding JSON metadata files
+  Example:
+  - pop_train_sad_aminor_85.mid
+  - pop_train_sad_aminor_85.json
+
+## Characteristics
+- Tempo: 70-95 BPM
+- Mode: Primarily minor keys
+- Rhythm: Smooth, fluid patterns
+- Mood: Emotional, melancholic, reflective
+
+## File Requirements
+- Format: MIDI files (.mid) with corresponding JSON metadata
+- Naming Convention: pop_train_sad_[key]_[tempo].[extension]
+- Example: pop_train_sad_aminor_85.mid
+
+## Musical Guidelines
+- Expressive melodic lines
+- Minor scales and arpeggios
+- Longer note durations
+- Emotional depth through intervals
+- 4/4 time signature
+- Strategic use of silence/rests
+- More complex harmonic implications