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Message ID: 9884     Entry time: Wed Apr 30 21:16:42 2014
Author: rana 
Type: Update 
Category: LSC 
Subject: MC2 Strad 

bettsreplica.jpg

I found the YARM LSC feedback going to MC2 and the MC2 violin mode (at 644.69 Hz) rung up. The existing notch was just a second order Twin-T style notch (so not a good idea) and also not turned on, since it was in the FM4 spot of LSC-MC2 and the vio triggers are ganged between all mirrors and don't touch FM4.

I copied the PRM vio bandstop into FM2 of this bank, deleted the old notch, and tuned the bandstop frequencies a little to get the violin peak into one of the zeros of the elliptic bandstop. Attached are the Y-arm / MCF spectrum with the mode rung up as well as the new filter's TF compared with the old notch.

P.S. I installed http://en.wikipedia.org/wiki/Midnight_Commander on pianosa.

Attachment 2: MC_Y_vio.pdf  172 kB  | Hide | Hide all | Show all
MC_Y_vio.pdf
Attachment 3: MC2_vio.pdf  16 kB  | Show | Hide all | Show all
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