(a) Abu Abd al-Rahman al-Sulami (may Allah have mercy on him) said: They used to say more takbir on Eid al-Fitr than on Eid al-Adha.
(b) Imam al-Shafi'i (may Allah have mercy on him) narrates from a group of the Successors that they used to say the takbir aloud in the mosque on the night of Eid al-Fitr, and used to say it aloud from the morning until going to the prayer ground.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة العيدين / 6132