What is the place of pronunciation (Uchcharan Sthan) for the vowels 'ए' and 'ऐ'?

The vowels 'ए' and 'ऐ' are joint vowels formed by combining $A/Aa$ (pronounced from Kanth) and $I/Ee$ (pronounced from Talu). Therefore, their place of pronunciation is Kanthatatavya (Kanth + Talu).