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Active filters in parallel

Hello,

I am in the process of building these three narrow bandpass filters (see schematic) I chose different values for each of the components (R1, R2, R3, and C). I was just wondering if placing these filters in parallel will change the filter characteristics I initially had? I am wondering because I took some quick measurements of each R1 (which is their 1k ohm resistor) and got a much different values (since all three R1's are in parallel) Will this change my filter characteristics?



http://makezineblog.files.wordpress.com/2010/10/ledcolororgan-schem_r2.gif
 
Not sure what you mean by "measurement of each R1" and how that would give different values from other measurements of R1. Nor can I see how the R1's are in parallel. What I can see is that any level adjustment with one of the 20K potentiometers will change the frequency characteristics of all the filters; however, since the resistance change should be small in relation to the 680Ω shunt resistors and the driving point impedance of the 4.7 μF capacitor, the effect should be negligible.
 
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