LessonsTafkhīm and Tarqīq — Alif, Divine-Name Lām and RāʾQuiz

The closing warning is balanced: do not make a light consonant’s fatḥah so thin that it resembles an unwarranted minor imālah. Likewise, do not overemphasize until fatḥah approaches ḍammah or alif approaches wāw.
The goal is moderation and accuracy: an appropriate sound colour while the consonant and its vowel remain identifiable. The book criticizes such over-thickening and over-thinning as departing from natural Arabic recitation.

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Avoid excessive thinning as well

Tafkhīm and Tarqīq — Alif, Divine-Name Lām and Rāʾ

The closing warning is balanced: do not make a light consonant’s fatḥah so thin that it resembles an unwarranted minor imālah. Likewise, do not overemphasize until fatḥah approaches ḍammah or alif approaches wāw.
The goal is moderation and accuracy: an appropriate sound colour while the consonant and its vowel remain identifiable. The book criticizes such over-thickening and over-thinning as departing from natural Arabic recitation.