Speaker Dimple

...if you listen in stereo you will find things to sound erratic and imaging to suffer.

Robr45 (System | Reviews | Threads | Answers)

Not true in my system. Imaging is spot-on.

Guess either my speaker didn't have an appreciable defect, or I have poor listening skills. Could be either...or both.

The purpose of the dome is dispersion.

It is very possible that your defect is inaudible.

I just used the vacuum method on a pair of Totem Mites I picked up in a thrift store for $35.00. I put two fingers in front of the hose to prevent a perfect seal should the nozzle come in contact with the dimple. Worked perfectly and after running them in for a while any sign of a crease was gone.

It is very possible that your defect is inaudible.
Robr45 (System | Reviews | Threads | Answers)

I believe this is true, and I'm thankful.

The point I am illustrating is that a dimple need not necessarily be the End of Days for one's system. Sometimes, audiophiles can get a little nuts about defects and this is one scenario where the defect, if small enough, might have no effect whatsoever on the system's sound.

Not true in my system. Imaging is spot-on.

It would indeed be more subtle than that.The dimple is a weak point that will succumb to flexure. The other issue will be dispersion. Think of how a phase plug or a waveguide changes the off axis response of a driver - same thing with a tweeter.

It is easy to show there will be a difference. For example, if your dimple is 1 cm deep right in the center of the tweeter then you will have quarter wavelength cancellation and a dip in the on axis response centered around 8500 Hz. This is probably not as bad as increased breakup or flexure though - as it may simply resonate/flex rather than behave as a piston and lose high frequency output/efficiency.

Remember that ring radiators do behave differently - so a dimpled tweeter will too.

Once you fix a soft dome then provided there is no permanent damage or crease then it should be as good as new (not unfortunately the case for a metal dome which will be toast)