Now here is another thought for your perusal.Overall, the tip has very little to do with the sound/noise. However, each will have an attribute. It also depends on what 'noise' you're trying to reduce. If an overall reduction, rather than targetting a certain set of frequencies (usually higher ones cause increased dB), use a double skinned tip.
let’s say you have two silencers of the same cross section but one is twice the length of the other.
would they dampen different frequencies?
both are 4x8 and one is 8” the other 16” long will have about a 1” gap between them.
the 16 first then the 8.
Absorptive or reactive silencers ?
https://www.acoustic...5/papers/34.pdf
Both are absorptive type.