Hmm, checking out Ghost on YouTube, they are pretty good!
Opeth for reference:
No growling:
https://www.youtube.com/watch?v=sAuL3AszIiE&list=PL_9gWeiShHFGZPQvoPc0vo7CtiQZUdM0R&index=3
With growling:
https://www.youtube.com/watch?v=YeTNkPXRrVY&list=PL_9gWeiShHFHzpU20PyVHiawAuPCJH9qH&index=4
Opeth for reference:
No growling:
https://www.youtube.com/watch?v=sAuL3AszIiE&list=PL_9gWeiShHFGZPQvoPc0vo7CtiQZUdM0R&index=3
With growling:
https://www.youtube.com/watch?v=YeTNkPXRrVY&list=PL_9gWeiShHFHzpU20PyVHiawAuPCJH9qH&index=4