Budgie question?

My 1 month old budgie's cage is in my room and I never hear him chirp. But today I took him out of the cage and put him on the couch in the family room. then I took my cockatiel and put her on the couch with him (shes scared of him by the way) anyway he started chirping and whistling like crazy i was shocked i never heard him like this before. Was he chirping and whistling because there was another bird there, or is it because he wasnt lonely anymore? Is he lonely in that room is that why he isn't chirping?
ive had my bird for only a week but he chirps near my cockatiel but not in my room or her cage. but actually on a very rare occasion he will acutally chirp in his cage like today he did two chirps and they were actually pretty loud, but i know budgie can and are more noisier then that especially males i heard and i want him to whistle and chirp i like it

I dont know why your bird doesnt chirp but I do know that NONE of mine will chirp unless they hear sounds near them. Such as other birds, the TV, birds outside chriping and so forth. How long have you had your bird could be he's not use to his environment yet