What is the ruling regarding the volume of the two salutations (Taslim) made by the Imam at the end of prayer?

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The preferred ruling, as narrated from Ahmad ibn Hanbal, is that the Imam must pronounce the first salutation loudly (Jahra), while the second salutation should be quieter than the first. This view is supported by the statement of Salih ibn Ali regarding Ahmad's opinion that the first salutation is louder. Al-Qadi Abu al-Husayn, Abu Bakr al-Khallal, and Abu Hafs al-'Ukbarī adopted this narration. The evidence cited for this distinction is based on the principle that audible pronunciation (Jahar) in non-recitation parts of the prayer is legislated solely to notify the congregation of the transition from one established pillar (rukn) to the next. Since the transition is accomplished by the first loud salutation, making the second one loud is unnecessary. Furthermore, the narration of Aisha, stating that the Prophet (peace be upon him) performed a single salutation, is interpreted to mean that he made one salutation audible enough to be heard by those present.