BFD (Behringer Feedback Destroyer) Parametric EQ "Setup Instructions Simplified" (1 Viewer)

[Ken Woodrow]

Sonnie:

Between you and Rick Radford, I have finally got my BFD up and running. Lot's more tweaking to go, but that's half of the fun!

One comment that Rick made may be worth incorporating in your guide:

"If the filter select key is unlit the number on the display

should be the preset number. If the filter select key is

lit, then the number on the display is the filter number of

whatever preset you chose. Hope that you're following me

here."

Somehow I missed this critical distinction b/n the presets and filters within the presets. The first few times I was actually setting up filters within subsequent presets, rather than multiple filters within the same preset. Needless to say, it didn't work!

Thanks again for your great guide.

- Ken

 

[Sonnie Parker]

Ken,

Maybe I'm stating it differently. But if you follow the instructions completely you should see this.

From the guide:

Set “FILTER SELECT”. (For each filter you setup.)

The bottom line is, I believe I cover this thuroughly. If I'm not following you then I'm lost myself. LOL! It's a lot of info and I've read it over 100 times (exaggerated) and still feel like I'm missing something. Then I go back and see I included it but said it a little differently than I was thinking. Of course, I'd say that each person is probably going to read it differently.....it's hard to word it for everyone. If ya know whut I mean!

SP

 

[Sonnie Parker]

Once again, I have modified the BFD webpage.

It can now be viewed in 800 X 600, although it is best

viewed in 1024 X 768.

Printing will still need to be in landscape or download the

Word document. *The Word document has not been completely

updated but will be within a few days or so.

Image dpi has been decreased for faster downloading of the

page. Obviously there is some loss of quality but it's

acceptable. Some image files were 100k to 300k in size and

all are now less than 60k and most are less than 15k to 20k.

There have been some modifications to the wording with some

additions.....nothing overwhelmingly significant.

Some typo's were modified on the page and in Ken Bruce's

review as well.

Again, I appreciate the interest, comments, suggestions,

etc...that I continue to receive. As stated earlier, I'd

like to make it the best BFD information source available.

I will continue to work on it on a regular basis for some

time to come.

SP

 

[Ken Woodrow]

Sonnie:

Thanks for the clarification and for the updated page. It's an invaluable reference tool, IMO. You're right about the information being in your original text -- I was simply missing it. It took Rick's translation to light the bulb in my head.

- Ken

 

[Sonnie Parker]

Thanks Ken,

You had me wondering. I kept thinking I was crazy but it was simply information overload I think. LOL! It was worded differently to an extent. No biggie...at least you got it figured out.

Rick has been a lot of help as well for me. He has picked my brain quite well and kept me on my toes.

It still needs some work but it will eventually get there. I'm not the absolute best with words so ????

SP

 

[Rick Radford]

>I don't believe this can be true in all cases. If the "FILTER SELECT" button is unlit, then other buttons may be lit and displaying that selected info.<
Sonnie, you're absolutely right. I was trying to differentiate between *presets* and *filters within presets* and wasn't precisely clear.
Fine, bandwidth and gain could all have displays which overlap the *preset* or *filter within a preset* range.
Fortunately, Ken was thinking along the same lines I was and I didn't confuse him further!
FWIW, I think that setting the BW properly is probably the most difficult thing to do. With an RTA program running, it becomes easy work to dial in a BW and see what happens in seconds.
But I can't imagine how long it would take to run the test tone CD, find the right tracks, make a note of the freqs and the response, plug the new numbers into the Excel graph and see if you've chosen a good BW. Thus far, I've found that my BW calcs aren't worth a hoot.
I can't emphasize enough how helpful a program like ETF5 has been for me. And the same for your site too!
BTW, I stopped by your site the other day and noticed that Opera now seems to be showing the same graphs and pics that IE does.

 

[Sonnie Parker]

I can't imagine how long it would take to run the test tone CD, find the right tracks, make a note of the freqs and the response, plug the new numbers into the Excel graph and see if you've chosen a good BW. Thus far, I've found that my BW calcs aren't worth a hoot.

It does take quite some time to run through the process. Once you do it 3-4 times it becomes faster and easier. I setup preset #5 the other day due to a temporary furniture crash (my recliner broke - ahh okay....I may have helped it break some). It took me about an hour. I took about 12 measurements.

The test cd I made is 21 tracks (16-160hz) at 10 second intervals. I have my Excel Workbook open and pop in the numbers. I look at the peaks and start guessing with the bandwidth settings.....I can get a general idea of what it should be, although I have surprised myself enough. I couldn't agree more that the calculations just plain ain't worth squaddly poot. I don't know about everyone else but I find myself using narrow bandwidths (2/60, 4/60, 8/60).

I can also agree that the ETF software program should make it faster. I would have to have a laptop....I can't move my computer.

Rick, maybe you could fix us up with a comprehensive guide on how to use the ETF program. What do ya think? I would love a link to such. And if there's anyone who has worked with Spetra Plus, a good guide for it would be nice for a link as well. I have plenty of space on my website if anyone needs it and I can put a page up if you give me the info.

I would like to request of Wayne A. Pflughaupt to help us get a write up on a "house curve". I think this is very interesting in equalization.

 

[Rick Radford]

>I don't know about everyone else but I find myself using narrow bandwidths (2/60, 4/60, 8/60)<
Same for me. Here are my last set of filter parameters:
Filter FrequencyBWGain
F1: 25+8/606/60-3
F2: 32+8/606/60-6
F3: 50-8/606/60-10
F4: 50+8/603/60-7
F5: 80+1/60 10/60+3
F6: 40+0/604/60-1
> I would have to have a laptop....I can't move my computer.<
That's what I thought too. But I'm getting the time down to about 20 minutes to take it down and set it back up in the HT room. It's still a PITA. But worth it!
>maybe you could fix us up with a comprehensive guide on how to use the ETF program<
Actually there's already a pretty good one here. One notable exception is that the RS mic correction file in section 3 doesn't work with ETF. ETF is not setup for mic correction below 500 Hz.
I know Jon was planning to update that site, but I haven't seen much activity there for a while.
w/r/t LF correction files for the RS spl meter, the author of ETF said:
*****
"I see that the RS mic has some discrepencies at these lower frequencies.
I am not going to be able to add low frequency calibration to ETF. The program can be improved more significantly in other ways.
To use the RS meter, you will have to visually add these low frequency changes to whatever you measure.
It probably looks like an easy task to add this calibration data - it isn't.
The problem is that the internal processing works at only 500 Hz and above.
I didn't anticipate LF calibration because our mics have always been "flat" to below 20 Hz. We have not yet done calibrated LF measurements."
*****
I struggled with this for a while before it finally dawned on me (with BruceD's help) that it really didn't matter. After all, if you get the response curve flat without the RS correction, you'll actually have your house curve built in. (~7 or 8 dB rise as the freq drops to 20 Hz)
If anyone could write up an ETF guide, BruceD is the man. The author of ETF also offers excellent support and has lots of info on the website. Plus, there are some resident experts here. I am still a grasshopper. (but happy to contribute where I can)

 

[jeff peterson]

Sonnie and Rick...thanks soooo much for the time you guys spent on this. It's been invaluable to me. I've got the 1124, the RS meter, and EFT5. I've also got a question
I have one peak that, according to EFT, is 8 db above my flat line. I dial in the center freq and a bandwidth and negative 8 on the gain. However, the peak doesn't come down enough (only about halfway to the flat line). I end up having to use around negative 25 to really get it flat. By that time, my SVS sounds "funny", so I put the gain back to negative 8 and let the peak still be partially there. My anal side has a hard time living with that but the other side of my brain is happy with the sound.
Note I didn't have this problem with ALL the peaks I reduced, just one. I'm wondering if my bandwidth wasn't wide enough and the EFT software doesn't have enough resolution to really show me what's going on. Maybe I should try 2 filters on the peak? I guess experimentation is in order but I'm looking for your guys opinions. Hopefully, I've explained it well enough.
Oh, and Rick, you're definately past the grasshopper stage.

 

[Rick Radford]

heh, got you fooled, Jeff! I know just enough to be dangerous! The more I learn, the more I see there is to know.
Since you have ETF, you can pretty much see what's happening in near real time. Have you found SDA mode yet? (Sequential Data Acquisition).
If not, once you take a reading, the lower right button on the graph becomes active (iirc). Click it and you gain access to SDA.
Reading the help file, I just discovered this note about the SDA loop:
>( Win NT4.0, Win 2000 Only). Not reliable in all Win 95/98 systems but will do no harm.<
If this works on your PC, you can make parameter changes on the fly and see the change onscreen in 1.5 seconds. Pretty cool! (sure beats the manual method)
If you want, zip up a LF response graph and shoot it to me. I may not have any better idea that you, but I'll look at it.
Make sure it's the .etf file and not a jpg. Since I have ETF I can manipulate it here.
In my anal way, I've been able to get my sub response to +1.3/-0.9 dB from 20Hz to 92Hz. (uncorrected) With the RS correction tossed in, I have a nice 6 dB rise as the freq decreases from 89 Hz to 16 Hz (according to the graph).

 

[Sonnie Parker]

Rick also wrote:

If anyone could write up an ETF guide, BruceD is the man.

Okay Rick, if you won't do us a guide to using the ETF, help me talk him into helping us write up one. Is this Ken Bruce (brucek) or is there a BruceD that I don't know?

 

[Brian Corr]

Well, reading your guide gave me the motivation to pick the the BFD. Found it locally at guitar center for $129.

I spent about 4 hours yesterday and 3 hours this morning tweaking. I ended up moving my sub from one corner to another due the the ability to get a flatter response. I am almost dead flat from 20-80 hz except for a 6-7db dip at 56hz. The bass does sound tighter now.

But one of the above statements has me confused. Is it better to have a gradually sloping curve rather than flat?

thanks for putting up the guide!

Also, I modded my RS SPL so I wouldn't have to worry about making the adjustments for the lower frequencies. It is cheap and easy (if you know how to solder) and I would recommend it.

 

[Sonnie Parker]

Brian,
That's pretty close to the same dip I have. I haven't noticed any loss in smoothness as a result though.
As far as the gradual slope detail goes, I'll refer you to another thread: house curve thread
My opinion is I like my sloping response better than my flat response. But it depends on your room size and your taste as to where the slope would begin and how much to slope it. You might experiment with it and see what you like. You've got 10 presets to do it with. Flip through each one of them replaying the same music or scene and see which one sounds the best to you.
The mod to the mic would be a good link on my site. I'd like to know how to do it as well, but I'd have to have very explicit details or I might screw it up. Would you mind giving me the details and allowing me to put up a page for it. I have plenty of web space.

 

[Brian Corr]

The site I used for the SPL mod is:
Link Removed

 

[Brian Corr]

Will you check out my graph and tell me what you think?
Link Removed
Sub location 2 after calibration is my current position and settings.
I changed the URL. See if that works. MSN is such a pain to use to post stuff!

 

[Sonnie Parker]

Thanks for the mod site Brian.

I couldn't get your sub graph site to pull up a graph. It takes me to a log in page.

 

[Sonnie Parker]

Everything is okay with the site. Occasionally our server will go down (you know how that can be sometimes) and we don't catch it quickly enough. I apologize for the inconvenience.