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FDS-366T Bessel filter implementation
arnaudf
Posts: 4
Dear BSS,
Since a few months, I own a FDS366T processor to filter my loudspeakers (2-way + biamping).
I already tried several filter setup (Butterworth, and L-R). I'm now trying the Bessel ones (particularly the 24db/oct).
However I need some information about their implemation in the 366T.
For example, how are they normalized ? (this Rane technote shows there are many ways : http://www.rane.com/note147.html)
I already remark that cutoff freq are based on -6dB, but I'm note sure...
I'm look for Bessel filters with the most possible linear phase and summed freq response.
I use an Excel sheet to simulate Bessel filters and it uses -3dB cutoff freq. In this case LPF and HPF are different.
Regards,
AF.
Since a few months, I own a FDS366T processor to filter my loudspeakers (2-way + biamping).
I already tried several filter setup (Butterworth, and L-R). I'm now trying the Bessel ones (particularly the 24db/oct).
However I need some information about their implemation in the 366T.
For example, how are they normalized ? (this Rane technote shows there are many ways : http://www.rane.com/note147.html)
I already remark that cutoff freq are based on -6dB, but I'm note sure...
I'm look for Bessel filters with the most possible linear phase and summed freq response.
I use an Excel sheet to simulate Bessel filters and it uses -3dB cutoff freq. In this case LPF and HPF are different.
Regards,
AF.
0
Comments
It seems that I have a beginning of answer.
Following the filter curves published in the \"original\" 366 manual (page 20), it seems that the crossover point for Bessel 24db is located around -7,5dB...
Thus the multiplying factors in the Rane technote seems to be ok (see § \"Rane's Bessel Crossover at -3 dB\" ).
If a gentle BSS engineer or forum guy have an idea, they are welcomed...
It would be nice if someone solve your problem
There is a cunningly titled 'support' page on the BSS website that will allow you to send a message directly to a technical support person in your timezone.