Cheap source for foam port plugs/bungs

Anyone who wants to experiment with plugging the port(s) on your speakers might be interested in this source I found for foam plugs. These are NOT audio-specific port plugs, they are just the appropriate size and foam density (see link at end of post).

The plugs are available in a variety of sizes, to accommodate port openings of up to 75 mm. I bought some of the 35-45 mm plugs for my ELAC Debut 2.0 F6.2 floorstanders (their ports are roughly 38 mm) and they work great to plug the lower two ports that vent the bottom chamber that holds the two 6.5 inch woofers. Very handy if you need to place the speakers closer to the wall and don’t want the resulting bass boom.

The F6.2 is a great candidate for this because it is essentially a B6.2 bookshelf (albeit with a rear-facing port) resting on top of an acoustically separate lower chamber with the two woofers.

The plugs are fairly short at roughly 1.75 inches, except for the 46-65 mm ones which are 3.5 inches long.

One possible cosmetic drawback for some people, the plugs are available in white only.

Oh, and the shipping charge is brutal, $24 as I recall. So make sure to buy other stuff on your order to make the shipping charge less painful. I got several boxes of vinyl gloves at a pretty good price.

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Good idea and welcome!

Brings back memories of genetics work with fruit flies (drosophila).

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Not available in UK due to GDPR regs, but these are lab supplies?
I shall look for something similar in the UK :slight_smile:

Another option is foam cord, like this material from McMaster-Carr in the USA. I tried it but it was a bit too soft, and it’s available in fewer diameter sizes (the length of the cords is 36 inches):

Plus it’s a PITA to cut in a perfectly straight line…

Interesting. I used a rolled up hand towel to plug my ports. Is there benefit to using foam?

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Open-cell foam permits some air flow, unlike a solid rubber plug. And because it is compressible, it enables a nice snug fit. But frankly, a carefully rolled-up towel could probably offer many of the same benefits.

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I went to the hardware store and bought a sponge for $1.75, cut it in half and inserted them in the rear ports. Sounded fine.

I used to use a rolled up pair of socks.

Just roll up open cell foam and cut to size. You can get a huge piece in the bedding aisle at Walmart. It is about $12. It conforms perfectly after a week. You do not want the bumpy stuff. If the bedding aisle does not have it, try arts and crafts by sewing.

Otherwise for real bungs Music Direct might sell you some. I cannot promise that.

For my EgglestonWorks Savoys I used Nerf balls cut in half (or I could have used them whole). They fit my ports perfectly.
My reason for plugging the ports was to better match my sealed JL Audio subs (helps with impulse and phase correction While using a JL Audio crossover).