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previous: SK Whenever possible I do not use the ... -- 5/8/2004 1:42 PM View Thread

Re: coupling magnet to adjustable polepieces

5/9/2004 12:34 AM
Dave StephensRe: coupling magnet to adjustable polepieces
What real measurable effect does the metal keeper have on the coil and output? Hewo said he thinks he sees a noticeable increase in output playing his guitar, but that seems a really poor way to test difference in output, you could be playing louder without knowing it.  
 
 
 
Is there a measurable increase in inductance? All the Korean copies I've taken apart have no keeper bar, maybe just because its cheaper to make it that way.  
 
 
 
Also the old vintage P90s I've taken apart don't have threaded keeper bars, they are very crudely made.  
 
 
 
Has anyone done resonant frequency analysis of a P90 with and without the keeper bar?  
 
 
 
I was making some P90s last nite and measured the coil without and with the bar magnets just placed on the coil without the pole pieces and the magnet itself adds a very measurable increase in inductance itself. Dave

 
Replies:
hewo correction:the guitar signa... -- 5/9/2004 7:35 AM