Reli said:
Those blue caps would look good on most Aiwas, as well as a GE 3-6035
Am I correct though, that the cap would need to be the same radius and curve as the original, in order to not cause any sound variation?
Dustcap curve & dustcap radius or diameter vs. Sound variation? No
The dustcap has a purpose and that purpose is not so much to do with sound.
The sound variation will usually be caused from another problem within the signal or transducer itself. Although if you placed a closed dustcap on a speaker that is designed to be cooled or vented from the dustcap (a dustcap with a screen, or holes in the cone located between the dustcap and coil for venting) you could have issues. With almost all boomboxes and their speakers this will never be an issue, they are low power and don't require vented dustcaps
I have listed in my opinion and with a little more research how most speakers work at least the "cone and dustcap" portion of the speaker...
For reference the cone is connected to the "suspension" at the bottom or smaller side, which is connected to the "voicecoil".
The "cone" at the other larger end is connected to the basket via the "surround".
The "surround", "Cone" & "Dustcap", "Suspension" & "Voicecoil" move as one piece keeping it in an axial position while moving to the signal.
The dustcap has to be larger than the voice coil in order to protect it and allow for the cone to be rigid for dampening.
The cone's purpose is to prevent any uncontrolable movements or excessive vibrations generated after the signal passes (by stiffening or dampening). It is also working to keep the movement in an axial direction.
If the cone is too stiff it can interrupt the starting stopping force of the signal and have a build up of energy. This build up of energy could cause your delicate copper wires of the voicecoil to fuse together in places. This creates a resistance in movement or a void in the signal. (in some cases you can check a speaker to see if it has been compromised by moving the coil back and forth lightly to feel any grinding within the coil).
Once the coil becomes over heated or compromised, the signal & magnetic field can become nonresposive.
In my opinion for boombox speakers dustcaps can be replaced as long as the dustcaps are somewhat close to original size
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