In the context of Islamic prayers, some prayers include recitations that are spoken softly or silently, while others are recited aloud. Here's an explanation of the prayers you mentioned and whether they involve silent recitation:
Subh: This is the dawn prayer, which consists of two units (rak'ahs). The recitation in this prayer is done aloud.
Jumu'ah: This prayer occurs on Friday, replacing the regular Zuhr prayer with a sermon. Like many other obligatory prayers performed in congregation, the recitation during Jumu'ah is done aloud.
Zuhr: This is the midday prayer, consisting of four units. During Zuhr, the recitation is done silently.
Isha': This is the night prayer, which consists of four units. The recitation in the first two units is done aloud, while the recitation in the last two units is silent.
From the prayers listed, Zuhr involves entirely silent recitation, as each unit of the prayer is recited quietly.