That seems restrictive (visually, at least). What is the difference in surface area of the 120mm inlet, and the two smaller outlets combined?
Additionally, the harsh angles would seem to create strange airflow internally. Wasn't your previous version more conical or tapered? How does the hard 90-degree at the end of the 120mm section affect flow?
Hi jstnryan the total combined output is 160mm so there is no airflow restriction. Yes the previous version was more tapered but these angles were used to cancel out the remaining sound waves from the inside resonating chamber. If you listen in the video you can really hear how muffled this one is compared to the last version or with no muffler at all.
Working on one last design that will actually use 4 pipes instead of two and might be the best design yet. This design has taken about 25 prints, tests and about 3 months to get it this low of a DB