Motordyne test pipes?

Motordyne

ART pipes are resonated alright. Much more than a regular resonated test pipe.

ART pipes use a side-branch Helmholtz resonator for better acoustic and resonance control. It is also why they cost more than regular test pipes.

These side-branch resonator reduces high frequency rasp like a standard glass pack but they also control midrange and low frequencies. It makes for a quieter and clearer sound with less rasp, less loudness and even less drone.

It is interesting to note that while it reduces drone, it gives your CBE a subtle infrasonic growl.

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