Using the BFD without subsonic filter? (1 Viewer)

[MichelF]

Hi,
I was worried about the lack of subsonic filter on the Behringer DSP1100P when using it for subwoofer EQ. I asked (email) Behringer why it is so and here is the answer I got from them:
"The DSP1100P cuts off under 20 Hz. This is due to the A-D converter. So, there is no need for a separate crossover or high-pass filter."
Would you really use it without an external subsonic filter? Did you try?
Michel

 

[Deane Johnson]

I don't use a sub-sonic filter with my 1100P and a Velodyne FSR-18 sub. Why would I want to?
Deane

 

[MichelF]

To protect your woofer!
Are you using the internal amp of your Velodyne sub? If yes it surely has an internal subsonic filter!
Perhaps my question was not clear: would you use the BFD with an external amp powering directly the woofer of a sub without any subsonic filter in the signal path and rely totally on the BFD to cut everything below 20hz?
Michel

 

[Deane Johnson]

I guess my Velodyne does have an internal sub-sonic filter. There is a switch to select 35 Hz or 15 Hz. I use 15 Hz. Never thought about it before since it was all taken care of in the design. I wondered why there was concern since I had never given it a second thought, now I know.
So far as using the BFD and depending on it to provide low frequency cut-off, I guess one has to decide whether they can count on BFD providing the right information or not. That's a tough call.
Hopefully, Tom V. or some one with more experience in DIY subs will jump in with an answer. I guess I shouldn't even have tried to answer your question since I obviously don't know the answer.
Deane

 

[MichelF]

Deane,
Thanks anyway
Michel

 

[Timmy]

"The DSP1100P cuts off under 20 Hz. This is due to the A-D converter. So, there is no need for a separate crossover or high-pass filter."

There is your answer.
The 20hz cutoff is not used, however, with the BFD in bypass mode. But who uses it in a disabled condition?
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