My experiences with the BFD (1 Viewer)

[David Judah]

We just moved into a new house a few months ago and I have been wanting to pick one up based on the recommendations here, so I went down to the music store and got a BFD 1124.
I hooked it up and spent a few hours figuring out how it worked and started taking some measurments with it in bypass mode. Now, I have always had some kind of nasty peak in our different apartments, so I figured it would be the same for the room in our house.
Much to my suprise from 26-80 Hz there was little variation(within 2.5-3 db) in the 6 square foot space I had to work with. I was up between 4-5 db at 20-25 Hz. These were crude measurments taken with Avia and an SPL meter(with corrections), so I know absolute accuracy was not possible, but at least the shape of the curve could be attained.
I really don't know if it is worth having the BFD in the LF audio chain just to tame a small peak between such a small range of frequencies at the lower end of the spectrum. I remember someone(Wayne?)even suggested that it's not really beneficial to flatten down below 25 Hz or so anyways.
Moral of the story:
Measure before you decide you need to make some changes.
DJ
Note: For those of you who do have peaks in your room, the BFD is everything that members have been saying about it--it performs very well after you figure out how it works(it's really not that complicated).

 

[Jeffrey Noel]

David, since it doesn't sound like you need it too bad, are you going to sell it? If so, let me know!

 

[Vince Maskeeper]

in the 6 square foot space I had to work with.

Yikes, and I thought my room was small...

-Vince

 

[David Judah]

The more I think about it, maybe I will set a very wide bandwidth and bring it down a few notches, so the valleys in the response aren't quite as low compared to the rest of the frequecy plateau.

Has anyone tried doing that?

DJ

 

[Wayne A. Pflughaupt]

David,
I expect your small space is contributing to the amazingly good readings. However, I am a little concerned here.
First, you say you took “crude measurements.” Second, you always had some nasty peaks at the old places, and you expected you had the same thing at your new place. It seems to me if you went from nasty peaks to the smooth response you measured, you would have noticed the improvement the first time you fired the system up.
So since you didn’t I’m really wondering about those measurements. I suggest getting a disc with individual1/6 octave or finer test tones (preferably sine wave) and take some accurate measurements before “rendering a judgment.”

I remember someone (Wayne?) even suggested that it's not really beneficial to flatten down below 25 Hz or so anyways.

That was indeed me who said that – quite a few months ago (wow, some memory you have, David. ). I was referring to was EQing for the house curve (where room response rises with the lower frequencies). I found that at about 30-35Hz things sounded better if response flattened, or at least the curve decreased. Beyond that point, you still want good response out to 20Hz (and beyond, if you can pull it off).
Happy Holidays,
Wayne A. Pflughaupt

 

[Kevin C Brown]

David- You have to get a better test disc.
The Avia disc runs through the frequencies too fast, and with C weighting, the response of the Radio Shack is way too slow to get an accurate picture of your response.
You have to get the Autosounds 2000 disc, or maybe that Stryker disc. (Or some other disc, or a PC card and software for your computer.)
The Auto Sounds 2000 CD does 1 Hz increments from 10 to 98 Hz. Each Hz is a track on the CD, 30s long.
http://www.autosound2000.com/Products/cds/index.htm

 

[David Judah]

Well, I'm going to not be so lazy and move the computer in the room, so I can RTA it with Spectra Plus tonight.
The BFD looks cool in the rack, so I don't want to have to take it back.
DJ

 

[Kevin C Brown]

Oops, that should have said with the "slow response" on the RS meter, which is the recommended setting for HT.
I'm jealous! The PC/software approach is much faster, and probably more accurate than me sitting next to my "sweet spot," with the RS meter held out at arms length in one hand, and the DVD player remote in the other, switching tracks on the Auto Sounds CD!

 

[David Judah]

Yep, the RTA made quite a bit of difference compared to the SPL meter alone. I managed to get more accurate readings and work out 3 minor peaks and a major one over about 4 hours or so. I think my wife is happy that the computer is finally back in the computer room.
I was able to bring my sub level up 3 db and the bass definitely sounds tighter now. This Forum is really great--first you guys motivated me to build my own subs and now convinced me to get a BFD. I am very pleased with the results although my wife thinks I and all of you are crazy.
DJ