Introducing the Borla Polyphonic Harmonizer Exhaust Technology [Polyphonic Exhaust Explained] 

By harmonizing exhaust sound using principles of music theory, Borla brings a new world of driving excitement to the streets, tracks and trails.
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Imagine many voices harmonizing together in a choir. When the right notes are sung together, an ethereal effect is created with dramatically more depth than a single voice. Pipe organs have done this for hundreds of years, using combinations of varying pipe diameters and lengths to form powerful chords. This technology caught the attention of our VP of Sales & Marketing David Borla, whose many years composing and performing in the music industry included a record contract with Sony. David worked with our R&D team to apply organ pipe mathematics to exhaust applications. The exciting result is the Borla Polyphonic Exhaust Harmonizer, which is now featured in select Borla exhaust systems.
These patent-pending units contain pipes of different diameters and lengths to create multiple exhaust notes that harmonize to deliver a clean, rich, full-bodied sound to the Borla mufflers. The mufflers then enhance this sound to the character and volume appropriate for our Touring, S-Type and ATAK® systems.
The limitless combination of pipe diameters and lengths allows Borla to tune each application so that the best notes and harmonics of specific engines are highlighted.
Thanks to the straight-through design of the Harmonizers, Borla customers get the ultimate in tuned exhaust sound with zero loss in performance.