If you pray isha alone then fajr and magrib are loud?
Answers
Reciting out loud in the prayers in which the Prophet (peace and blessings of Allaah be upon him) recited out loud, and silently in the prayers in which he recited silently, is one of the Sunnahs of prayer, not one of the obligatory duties. But it is better for the worshipper not to go against the Sunnah of the Prophet (peace and blessings of Allaah be upon him).
Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) said:
Reciting out loud in the prayers where this is done is not obligatory, rather it is what is better. If a person recites silently in a prayer in which it is prescribed to recite out loud, his prayer is not invalid, because the Prophet (peace and blessings of Allaah be upon him) said: “There is no prayer for one who does not recite the Essence of the Book (al-Faatihah).” He did not specify whether this recitation is to be out loud or silent. So if a person recites what he is required to recite, silently or out loud, then he has fulfilled his duty. But it is better to recite out loud in the prayers where doing so is customary, as in Fajr and Jumu’ah prayers.
If a person deliberately does not recite out loud when he is leading the prayer, his prayer is valid but it is lacking.