Prelude Op.28 No.15 (Raindrop) in D Flat Major 雨滴前奏曲 作品28之15 降D大调

The Prelude Op. 28, No. 15, by Frédéric Chopin, known as the "Raindrop" prelude, is one of the 24 Chopin preludes. It is one of Chopin's most famous works.[1] Usually lasting between five and seven minutes, this is the longest of the preludes. The prelude is noted for its repeating A♭, which appears throughout the piece and sounds like raindrops to many listeners.

Some, though not all, of Op. 28 was written during Chopin and George Sand's stay at a monastery in Valldemossa, Mallorca in 1838. In her Histoire de ma vie, Sand related how one evening she and her son Maurice, returning from Palma in a terrible rainstorm, found a distraught Chopin who exclaimed, "Ah! I knew well that you were dead." While playing his piano he had a dream:

He saw himself drowned in a lake. Heavy drops of icy water fell in a regular rhythm on his breast, and when I made him listen to the sound of the drops of water indeed falling in rhythm on the roof, he denied having heard it. He was even angry that I should interpret this in terms of imitative sounds. He protested with all his might – and he was right to – against the childishness of such aural imitations. His genius was filled with the mysterious sounds of nature, but transformed into sublime equivalents in musical thought, and not through slavish imitation of the actual external sounds.

Sand did not say which prelude Chopin played for her on that occasion, but most music critics assume it to be no. 15, because of the repeating A♭, with its suggestion of the "gentle patter" of rain. However, Peter Dayan points out that Sand accepted Chopin's protests that the prelude was not an imitation of the sound of raindrops, but a translation of nature's harmonies within Chopin's "génie". Frederick Niecks says that in the middle section of the prelude there "rises before one's mind the cloistered court of the monastery of Valldemossa, and a procession of monks chanting lugubrious prayers, and carrying in the dark hours of night their departed brother to his last resting-place."
The prelude opens with a "serene" theme in D♭. It then changes to a "lugubrious interlude" in C♯ minor, "with the dominant pedal never ceasing, a basso ostinato". The repeating A♭/G♯, which has been heard throughout the first section, here becomes more insistent.

Following this, the prelude ends with a repetition of the original theme. Frederick Niecks says, "This C♯ minor portion... affects one like an oppressive dream; the reentrance of the opening D♭ major, which dispels the dreadful nightmare, comes upon one with the smiling freshness of dear, familiar nature – only after these horrors of the imagination can its serene beauty be fully appreciated."

前奏曲Op. 28, No. 15为萧邦24首前奏曲中的乐曲，为降D大调，延绵（Sostenuto），4/4拍。此曲为时5-7分钟，为作品中时间最长的前奏曲。

阿尔弗雷德·科尔托将其称为“但死亡在这里，在阴影之中”（Mais la Morte est là, dans l'ombre），汉斯·冯·毕罗将其称为“雨滴”（Raindrop），而现在“雨滴”这一绰号是广为人知的。
乔治·桑记述了萧邦一次弹琴时发了一场梦：

“
他看见他淹在湖里。冰冷的水重重地、有节奏地打在他的胸膛，而当我使他聆听水滴有规律地打在屋顶时，他否认他曾听见这声音。他更为我把它（乐句）视为声音的模仿感到愤怒。他尽所有力量抗议这幼稚的模仿（他是有道理的）。他的天分充满了自然神秘的声音，并将其转换为音乐的见解，而非一味模仿外来的音效。

她没有指出上述故事源自哪首前奏曲，而以与雨声类似一点来看，不少评论认为是这首。但另一说认为第六首也有可能。
此曲由一平静的旋律开始，从第28小节开始转为升C小调，旋律换到左手的低音部，较为厚重、具戏剧性，并且渐强至极强音，与开首形成强烈对比。于第76小节又转回降D大调，开首旋律重新出现。重复的降A音（在中间段以升G音标记）一直贯穿全曲，但在第二部分该音显得更为突出，亦使这部分更为阴沉。