hi there. ive tried the FRD stuff but can seem to get them to work.
is there any other way i can input my drivers freq resp and then 'subtract' the filters BW from the plot?
i was thinking of an excel sheet, with the equation of the filter graph plugged in? however i derive that....
anyone got any advice?
is there any other way i can input my drivers freq resp and then 'subtract' the filters BW from the plot?
i was thinking of an excel sheet, with the equation of the filter graph plugged in? however i derive that....
anyone got any advice?
anyone be able to tell me/point me the way to the MATH?
would anyone be able to point me in the right direction or tell me the MATH to allow me to subract the roll off in a filter. i.e. the equation for the curve/s, so i can calculate the attenuation at any given frequency with a given value of L and/or C, for the differnet types of crossover filter.
or am i being shortsighted and know how to do this?
can anyone remind me/ help me out here?
would anyone be able to point me in the right direction or tell me the MATH to allow me to subract the roll off in a filter. i.e. the equation for the curve/s, so i can calculate the attenuation at any given frequency with a given value of L and/or C, for the differnet types of crossover filter.
or am i being shortsighted and know how to do this?
can anyone remind me/ help me out here?
In order to predict the interaction of the filter components with the driver, you need to measure the impedance of the driver across the entire range of operation. So you need the "ZMA" files that are generated by most measurement tools. Once you have that, you need to solve some fairly long equations to calculate the voltage at the driver terminals. Then multiply by the driver response. You can use the program at the link to see the effect of the components in the crossover on the response. Just use the mouse wheel to scroll through different L and R and C values--it's pretty cool to see how the crossover interacts with the driver. You can find some sample response files (FRD and ZMA) at Roman's web site--http://rjbaudio.com/Audiofiles/Driver%20FRD%20files.html.
Alpha version of Passive Speaker Designer
Note: this program may take a while to install because it uses .NET4 and has database components that need to be installed (it's got the TS parameters for PE's woofers). Might be a few updates required...but it is all coming from Microsoft.
Looks like you need to right mouse click on the file and "save as" (zip file)
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thanks all for the input ill have a try at both, and maybe try the FRD tracer tool thingy again. i didnt have any success getting it to work last time, maybe its vista? anyway its worth another shot im sure, since there just isnt much zma & frd data available. even the audax data on the rjaudio page, without meaning any ill; it is not clear of measurement tech/test method/just inaccurate, OR should i say it is NOT infinite baffle nor DIN baffle, probably IEC, or a test box. unfortunately Boxsim doesnt cater for IEC.... hence i unfortunatly dont trust the data of others
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