It's been a long while since I was last here, but I simply must share this. Not long ago I got this idea, that really improved the performance of my speakers to an incredible level. This tweak makes the lower mid and bass both much faster, more precise, and to a certain degree, deeper.
The tweak is actually quite simple, but if you think about it, you'll find that it makes a lot of sense. The effects of it are like this:
1) It stiffens the speaker walls (All types of speakers)
2) It controls the airflow withing the speaker (Ported speakers)
3) Breaking up standing waves within the speaker (All types of speakers)
Of course I do not expect any of you to perform this stunt on your 50k $ speakers, but if you - like me - own a modest set of speakers, you will most certainly benefit from it. I have to emphasize, that I have no experience with non-ported speakers, why I cannot speak of how or even if, they would respond as expected. Also this is a non-reversable tweak, so be careful in conducting every step. That being said, I am confident that this tweak can be carried out on any speaker or subwoofer, that is ported.
1) Go buy some wood glue that can be thinned with water. I used the common type, that hardens in about 24 hours, and get almost transparent when completely dry. I ended up having to buy about 3 litres for 2 small speakers and a subwoofer.
2) Strip the speaker of ALL internal stuff, except the port itself, e.g. the speaker units, the crossover, wires, foam etc. Take great care not to damage anything during this process.
3) Place the empty cabinet on a table, and put an old towel under the cabinet to soak up any glue spills.
4) Get hold of some cardboard tube. I used a tube about 5 inches in diameter, and of a rather thick material (3 mm).
5) Measure the inner width of the speaker in question.
6) Cut 3 lengths of the tube, that would fit the inner width of the speaker. A sharp breadknife will do the trick.
7) Now split them LENGTHWISE down the middle. You should now have 6 split pieces of tube looking like gutters. These 6 pieces will do for the side speakers, as you should use 3 inside the left speaker, and 3 inside the right speaker. You'll need another set for the subwoofer.
8) Here comes the tricky part. Take a good look at the image below. It illustrates how I have placed the "gutters" inside the speakers. Be very careful to place them, so that they are not occupying any space right in front of the inside port opening, or where you'll need to fit the crossover or the speaker units. In other words, the "gutters" need to be placed more or less around the center of the space inside the speaker.
It is no coincidence that the "gutters" are turned like they are. The way they are turned maximizes the "breaking effect" on the airflow that they cause: When air is sucked inwards, the tubes do not apply a breaking effect, but when the air is pushed outwards, they do. This is what makes the lower mid and bass much faster and more precise.
9) Now that you have placed the 3 "gutters" inside the first speaker, measure where you have placed them. You will need to place the 3 other gutters about the same inside the second speaker.
10) Now lay the speaker down sideways on the towel. Pour into the inside of the speaker cabinet (the wall that is the downward side) just enough glue, so that all of the side wall is completely covered with glue.
11) Leave it to dry for at least 24 hours. Don't worry about fumes; it won't give you any headaches or discomfort.
12) When dry, do the opposite inside speaker wall. Leave it to dry.
13) Continue until all inside baffles are completely covered with glue. Use a brush on the inside of the front wall, and also paint a fair amount of glue onto the gutters.
14) When dry and finished, assemble the speaker. Take great care not to damage anything during this process. You'll need to cut up into smaller pieces any foam, that belongs on the 2 inside side walls, as the gutters now are permanently fixed onto these.
15) When assembled, connect the speaker, and do a "hand/knuckle test" on the outer side walls of first the tweaked speaker, and then the untweaked. You will surely be able to tell the difference in the amount of vibrations from the two speakers. If you are able to turn down the volume on the left vs the right speaker, you will also be able to detect the clearly audible improvement in the lower mid/bass performance of the tweaked speaker.
If you have fucked up anything during the procedure, well, do not blame me, but yourself, as you have not followed my instructions at some point.
On the other hand, if you have succeeded, you can proceed to the second speaker, and later to the sub, which will alltogether provide a jaw-dropping improvement in speed, precision, "aperiodic" and deep, tight bass.
Kind regards to all on SP