The 12 is not too noisy when you are in the pressurised capsule at the pointy end. (The freight bay is un -pressurised, so it is preferable to be in the capsule.
) I equates the sound level as similar to the C130K round about the para door area. Nice and cosy in the An12 when all 10 of us were in the capsule........ The An22 was similar in the air if you were on board, but on or from the ground, the noise was H O R R E N D O U S. Similar to the 12, pressurised crew capsule and un-pressurised freight bay. Enjoyed my time with them.
SNF