Materials: IKEA SODA, paper core, scissors
Description: I have plenty of SODA laying around, and a bunch of paper cores. I combine these items to built a DIY airflow straightener.
Cut the SODA straws according to the length of the paper core you're going to use. Then stuff in more straws inside the core until it's stiff and it won't slide easily.
I used one of these to significantly reduce port noise from a cheap PC subwoofer. Then I use another one as an attachment to my vacuum cleaner to make close-up vacuum more powerful.
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Neat idea!
ReplyDeleteI'm genuinly curious: why would I need an airflow straightener?
ReplyDeleteHi! A guy who designs speakers here...
ReplyDeleteIs this mod a panacea? No, but in certain cases it's a great trick to know.
What he's done is made the port more restrictive by increasing the port losses due friction. This does reduce the airspeed in the port. It also has the effect of raising the box tuning slightly, and improving power handling a bit (probably not a bad thing).
If something is horribly mistuned, this won't do enough to fix it. But it certainly doesn't hurt to try. If you don't like the sound, it's easily reversed!
I design speakers too. I hate to say this because I don't want to seem negative, but this mod doesn't really serve a purpose. Like the previous poster said, the restriction of airflow will raise the tuning and decrease the low-frequency response. I don't understand why you thought you needed to "straighten" the airflow of your subwoofer port. A port is simply a tuning device that is designed to increase the low-frequency output of a speaker system. This is beneficial in a home audio environment. It is normally better to have larger diameter ports because the velocity of the air is reduced compared to a smaller port. This reduces the amount of air noise that comes through the port. I hope that this modification didn't effectively turn your subwoofer into a sealed enclosure or create port noise.
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