What is a phase plug? (1 Viewer)

[GrahamT]

I read that Adire is redesigning the "phase plug" on the new 4" XBL^2 driver to increase the high end frequency extension. I cant figure out what a phase plug is and have had no luck searching.
Can someone please explain what part of the driver this is and how it affects frequency response.
Thanks

 

[ThomasW]

It's the little cone shaped device that's placed right in the middle of the driver. They smooth out the high frequency response.

There's one in this pic.....

 

[GrahamT]

Thanks Thomas,
Is it an extended part of the pole piece or is it part of the diaphragm like a normal dust cap.

 

[TimForman]

Scroll down to near the bottom of this page to see pictures of a phase plug I added to some drivers. I cut off the dust cap with a small, very sharp, hobby knife.

 

[GrahamT]

Thanks Tim. So they are tapered "bullets" that sit on the pole piece right? Cool website BTW

 

[TimForman]

They are just a bit smaller than the spindle (1mm or so)and sit inside on top of the pole piece. This eliminates what is typically a hollow chamber under the dust cap that can create that little bit of HF distortion that makes you say, "what the heck is that?".
Thanks.