In-ear headphones have the ability to reject outside noise without any noise cancellation device. They block outside noise by being properly inserted into the ear canal. This is a physical operation. You are shutting outside sound by blocking it to reach the ear canal by inserting and closing the ear by earbuds. These earbuds then shower music inside the ear canal, thereby giving music only and blocking outside noise. In noise isolation, no electronic device or power is used.
Over-Ear Headphones are also known as full-size, circumaural or around the ear headphones. They are the traditional large headphones with ear pads that fit around the entire ear. Over-Ear headphones come in either open or closed ear cup designs and offer the best sound quality and excellent comfort. They are my favorite and I enjoy music with my QC35 (old Model).
Why we need over-ear headphone because putting earbuds in the ear canal gives some sort of inconvenience and tingling. They give discomfort. Over-earphones comfortably cover the ear. Although noise isolation is little less than earbuds but they still stop outside noise and give only humming noise. The second advantage of over-ear headphone is they are configured for active noise isolation also.
Over-ear headphones give better bass than on-ear headphones. The quality sound output of in-ear headphones is limited whereas over-ear headphones provide the best quality sound output. Ask any audiophiles and they will recommend only over-ear headphones.
If you want the most consistent, very best possible sound in a headphone, you are likely to end up with some sort of over-ear model.
The best available over -ear Headphones of 2019 are-