# BFD just setup could use some advice.



## vrmarkii (Mar 28, 2008)

Hi, 
I just got my bfd setup yesterday and I'm having some problems. I've been reading the manual and the BFD guide and started messing with it today. Sofar I've set the switches on back to -10db and set the input gain so it wouldnt clip. I took some baseline measurements and went to set my first filter and here is where things went screwy. I'm not using rew just a RS spl meter maually for now. I burnt the 6th octave sin wave cd from the downloads section and am using that to take my measurements with. Here are my raw uncorrected measurements. 

Hz SPL
16 85
18 85
20 85
22 86
25 84
28 86
31.5 88
36 92
40 94
45 96
50 101
56 97
63 89
71 96
80 100
89 96
100 91
111 88
125 78
142.5 85
160 80 

So I set my first filter at 50 hz, -8 db, and tried a bandwidth of 20/60, 10/60, and 5/60. All 3 different configurations had an unintended side effect of a 3-11db drop everywhere below 50 Hz.

These measurements were with the bandwidth set at 5.
Hz SPL
16 84
18 86
20 75
22 78
25 81
28 80
31.5 78
36 81
40 91
45 93
50 93
56 95
63 89
71 95
80 100
89 98
100 91
111 88
125 79
142.5 86
160 82

If anyone has any ideas on settings to check or anything I'd appreciate it. I'm begining to think I'm better off without the BFD.


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## brucek (Apr 11, 2006)

The jpg below is a 50Hz filter at -8dB with a 5/60 bandwidth.

You can see it won't have the effect you're experiencing.

I would say you have entered something not quite correct....









brucek


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## Wayne A. Pflughaupt (Apr 13, 2006)

It appears that the filter you used at 50 Hz had the intended consequence of cutting the 50 Hz peak by 8 dB. As to the issues below 50 Hz, that could be accounted for by extraneous noises going on in or outside the house while the measurements were being taken the first time - like the air conditioner running, for instance. 

Or, there could be other filters activated that you weren't aware of. How many of the horizontal red LEDs do you have lit up? If there is more than one, then other filters are in use.

Regards,
Wayne


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## vrmarkii (Mar 28, 2008)

Thanks guys, I figured it out. I did'nt have all the filters for preset 4 set to pa. So After the first run through the cd it was creating filters. I got it dialed in pretty well now considering what I'm measuring with. Hopefully soon I'll be able to get a behringer mike setup with rew to do this a little more accurately. Now that I have it working correctly I got to say it works pretty awesome.


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