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Philco 38-690 tweeter improvement
#21

Dave Slusarczyk Wrote:thanks guys,

I know have a couple of things to try. One of which is this "whizzer"? Clue me in Syl. What in Gods name is a "whizzer"? Icon_confused

Dave

Quote: whizzer: a small, light cone attached to the joint between the voice coil and the primary cone. The whizzer cone extends the high frequency response of the driver and broadens its high frequency directivity, which would otherwise be greatly narrowed due to the outer diameter cone material failing to keep up with the central voice coil at higher frequencies. The main cone in a whizzer design is manufactured so as to flex more in the outer diameter than in the center. The result is that the main cone delivers low frequencies and the whizzer cone contributes most of the higher frequencies. Since the whizzer cone is smaller than the main diaphragm, output dispersion at high frequencies is improved relative to an equivalent single larger diaphragm.
http://en.wikipedia.org/wiki/Loudspeaker

[Image: http://i156.photobucket.com/albums/t25/w...hizzer.jpg]

Bill

It's not what you don't know that hurts you it's what you know that's not so.


Messages In This Thread
Re: Philco 38-690 tweeter improvement - by Syl - 07-25-2008, 10:16 AM
Re: Philco 38-690 tweeter improvement - by Syl - 07-25-2008, 08:19 PM
[No subject] - by Ron Ramirez - 07-25-2008, 09:39 PM
[No subject] - by wonderwrench - 07-25-2008, 09:52 PM
[No subject] - by Ron Ramirez - 07-25-2008, 10:49 PM
[No subject] - by Dave Slusarczyk - 07-25-2008, 10:53 PM
[No subject] - by wonderwrench - 07-25-2008, 11:06 PM
[No subject] - by Ron Ramirez - 07-25-2008, 11:06 PM
[No subject] - by Ron Ramirez - 07-25-2008, 11:13 PM
[No subject] - by Dave Slusarczyk - 07-25-2008, 11:59 PM
[No subject] - by BDM - 07-26-2008, 12:40 AM
[No subject] - by wonderwrench - 07-26-2008, 12:48 AM
[No subject] - by wonderwrench - 07-26-2008, 01:30 AM
[No subject] - by Syl - 07-26-2008, 08:33 AM
[No subject] - by Ron Ramirez - 07-26-2008, 09:20 AM
[No subject] - by Syl - 07-26-2008, 11:52 AM
[No subject] - by Dave Slusarczyk - 07-26-2008, 03:33 PM
[No subject] - by wonderwrench - 07-26-2008, 03:47 PM
[No subject] - by wonderwrench - 07-26-2008, 03:53 PM
[No subject] - by Ron Ramirez - 07-26-2008, 04:40 PM
[No subject] - by Syl - 07-26-2008, 04:51 PM
[No subject] - by Syl - 07-26-2008, 04:55 PM
[No subject] - by Dave Slusarczyk - 07-26-2008, 05:50 PM
[No subject] - by Syl - 07-26-2008, 07:17 PM
[No subject] - by Dave Slusarczyk - 07-26-2008, 09:26 PM
[No subject] - by Syl - 07-26-2008, 11:11 PM
[No subject] - by Dave Slusarczyk - 07-27-2008, 01:02 PM
[No subject] - by Terry Judkins - 07-27-2008, 05:59 PM
[No subject] - by wonderwrench - 07-27-2008, 06:11 PM
[No subject] - by Dave Slusarczyk - 07-27-2008, 06:53 PM
[No subject] - by wonderwrench - 07-27-2008, 09:00 PM
[No subject] - by Syl - 07-28-2008, 10:21 AM
[No subject] - by Dave Slusarczyk - 07-28-2008, 05:10 PM
[No subject] - by BDM - 07-28-2008, 05:17 PM
[No subject] - by Ron Ramirez - 07-28-2008, 05:59 PM
[No subject] - by Dave Slusarczyk - 07-28-2008, 06:12 PM
[No subject] - by Syl - 07-28-2008, 08:33 PM



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