There are two kind of pipe, pressure equalization and sonic equalization.
Crossplane crank V8s have pressure equalization (aka X-pipe) because V8 are not even firing on their banks, L R L L R L R R
V6s, flat plane crank V8, inline 6s, boxing 6s, even firing V10, even firing V12s have sonic equalization. The developed exhaust pressure is equal in equal exhaust system, so only sound waves are shared.
Without an equalization pipe, your V6 will sound like two inline 3s work together (like a porsche 911-no equalization there)