One way to think of the difference between volume (CC&) and gain (CC11) nodes is to visualize buckets.

Volume (CC7) is the equivalent of bucket size. I can have one quart, one gallon, three gallons, five or seven gallon buckets. In all cases the maximum amount of liquid I can pour into each bucket is limited by the size of the bucket. I can have one gallon of liquid but I will never fit all the liquid into the one quart bucket.

Gain (CC11) reflects the amount of liquid held inside a bucket. The amount of liquid inside a bucket can range between 0 for empty to 127 for full but the amount of liquid can not exceed the bucket's capacity when it is full.

Volume controls track level in a mix. Gain controls track dynamic level.
Jim Fogle - 2020 BiaB (721) RB (Build 3) Ultra+ PAK
Cakewalk - Zoom MRS-8 recorder
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