BFD Settings Recommendation (1 Viewer)

[Chuck Bogie]

For the second channel of the BFD...

Call Parts Express, and order a few boxes of Bass Shakers, and a 100 watt plate amp for each sofa. Use four shakers per sofa, wired for a 4 ohm load, and enjoy.
Punch the BFD wide a little low, and cut hard/wide above 80hz...

 

[Chris Huber]

Filter Freq Gain B/W
1 21(20+4) -5 10
2 33(32+2) +3 5
3 40(40+0) -30 10
4 45(40+10 -10 5
5 55(50+8) -9 3
6 63(63+0) +6 10
7 70(63+8) +6 2



Here is my newest edit of frequencies... I wanted to leave a bit of low end and start the curve from there... I ended up watching Episode V last night and things sounded pretty good.

I still could not tame the 80-89 peak... I set a filter at 84Hz, gain -20 and B/W 10, but this did not come down. I played the 80 and 89 signwave, and felt the main woofers making vibration as well as the sub.


Now that I am going to stick with these settings for a while, if I wanted to turn up the sub vol a bit, should I turn it up on the sub vol or AVR sub vol? Does it make a difference? If I turn it up on either, my graph will no longer be correct, right?

 

[Wayne A. Pflughaupt]

”Correct” is relative. You will merely see everything below 80 Hz or so uniformly rise.

Regards,
Wayne A. Pflughaupt

 

[Chuck Bogie]

Uh... Could be that that 80hz area is getting some help from your mains? What's your crossover set at? Can you turn down a crossover on your sub amp?

 

[Chris Huber]

Yes, my mains are helping. I can feel them moving when I play atest tone. Also, my sub is adjustable to 120hz(which is sits at now), but AVR only has 100Hz setting(where it's set now).

 

[Max F]

You seem confused.

All we are trying to tell you is to turn up the sub so that the line below 80 hz move uniformly up. Bring that line up around 5 db so that it will be closer to the peak at 80hz. You can turn up the sub with the receiver or on the sub. However, if the input lights are not coming on while listening at a comfortable volume then turn up the sub using the receiver so that there is an adequate input signal. Does that make sense?

 

[MikeNg]

Chris,

Also try lowering the crossover setting on your sub. See how it sounds at 60, then 80, then 100. It might not make a difference with the 80Hz peak since you applied a -20dB cut on the BFD and it did nothing, but it's worth a shot.

Just curious, but did you try your test tones with the sub off to see what your mains are exclusively doing?

Mike

 

[Chris Huber]

Ha, a little. I was alot more confused at the beginning of this thread Anyway, so my flat bass line EQed ~75db accross should be turned up on either the AVR or Sub vol ~ 5db to 80db? What I know this would put some sub bass back into things, but what would this do for my 80-90Hz peak?

 

[MikeNg]

The gain boost would only affect what's coming out of the sub, not the main woof's. Your 'net effect' may be a flatter response in that region. This assumes that you've rolled off that part of the spectrum on the BFD. Looking at your settings it doesn't appear that you did. Maybe set another filter at 85Hz, Gain = -10, BW = 10 - 15.

Mike

 

[Sonnie Parker]

Chris... I'm not sure if you ever got that peak at 80-89hz lowered but I would suggest you disconnect your mains altogether while measuring your sub. The idea behind the BFD is to strictly get your sub response set to the curve you desire, be it flat or house. I'd be willing to bet once you disconnect your mains you'll se that peak go away, and if you still have that filter cut set you'll probably see that peak is now a huge dip.

Also keep in mind that LFE will provide information up to about 120hz to your sub so you want to set the crossover on your receiver between your sub and mains to 80hz or typically about double what your mains are rated down to. You can vary that but generally 80hz is good. Then on your sub itself set it to 120hz. If you set it lower than 120hz you will not hear LFE between the crossover point on your sub and 120hz.

 

[Jim J]

did you try reversing the phase on the sub? might help the 80 hz peak

 

[Chris Huber]

So, the BFD cannot boost anything below the 20Hz mark?

 

[Sonnie Parker]

It will boost below 20hz but you cannot center the filter bandwidth at below 20hz.

For example... you can set a filter with a center frequency at 20hz... you can set the bandwidth to be 1/6 octave wide (10/60)... it will boost/cut down to 18hz, but the boost/cut will also reach up to 22hz. Naturally the boost/cut will be more at the center frequency than the outer frequencies. You could set the bw to a 1/2 octave wide (30/60) and it will reach down to 15hz and up to 30hz.

So... if you want to boost below 20hz you can do it. Once you set your filter up and boost however far below 20hz you want ot boost then you may have to set up filters to cut what it boosted above 20hz. It would probably take a lot of unnecessary filters and would most likely strain your amp more than you'd want it to.