# Old BFD design software still available???



## Guest (Oct 19, 2007)

I need a program to manipulate curves in so that I can creat different house curves for REW. The old BFD design software that is pictured in some of the house curve information on this site would be perfect but I can't seem to find a download for it.

Thanks,

Jason


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## Otto (May 18, 2006)

I'm not sure I understand. You can create house curves in a .txt file. They don't need to be perfectly rounded.


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## Guest (Oct 19, 2007)

That would be true for a simple house curve, but I want to create other curves as well, such as one that rolls off the low end below 30 hz for higher spl listening. I have a program that I can trace spl graphs and conver them to text with. So what I need is a spreadsheet that will allow me to draw curves centered around 0 db. The easiest way to draw curves would be with a parametric eq simulator such as the old BFD design software I mentioned. I could use REW but it will not let you set the target level low enough to get the curves near 0 db.

Thanks,

Jason


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## brucek (Apr 11, 2006)

Why can't you create the curves around a 75dB target and then when finished, use the Trace Offset feature to add -75dB and then click Add offset to data?

brucek


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## Guest (Oct 19, 2007)

brucek said:


> Why can't you create the curves around a 75dB target and then when finished, use the Trace Offset feature to add -75dB and then click Add offset to data?
> 
> brucek


Bruce,

I am using a spreadsheet called SPL Trace and I don't see any "Trace Offset" feature in the menues. Are you using a different spreadsheet?

I tried cheating by fudging the aligment values by telling SPL Trace that the levels on the graph were much lower than they were but it threw the scale off and my curve was much sharper than intended.

Maybe I am going about this the wrong way. If you were to create a target reponse that wasn't just a simple house curve how would you go about doing it?

Thanks,

Jason


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## brucek (Apr 11, 2006)

> I am using a spreadsheet called SPL Trace and I don't see any "Trace Offset" feature in the menues. Are you using a different spreadsheet?


I was referring to using REW...................... in response to your statement , _I could use REW but it will not let you set the target level low enough to get the curves near 0 db._

brucek


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

Not sure I’m getting what you’re after either, but...



> That would be true for a simple house curve, but I want to create other curves as well, such as one that rolls off the low end below 30 hz for higher spl listening.





> If you were to create a target reponse that wasn't just a simple house curve how would you go about doing it?


...you can create any kind of house curve you want in REW. For instance, I use the following values in a .txt file to get a straight-line, hard-knee house curve...

30 0.0
32 -0.5
45 -3.9
60 -5.9
75 -6.6
90 -6.0

...which looks like this:







​

You could easily add values to the top to make response slope down after 30 Hz...

10 -36.6
16 -20.5
22 -9.3
28 -0.5
30 0.0
32 -0.5
45 -3.9
60 -5.9
75 -6.6
90 -6.0

...and REW would display them as a target that looks like this:







​

Naturally, you can use whatever values you want to get the below-30 Hz slope you're after.

Regards,
Wayne


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## Guest (Oct 20, 2007)

Thanks all,

Bruce's reply gave me an idea and I can get REW to do what I want now. I started by creating a text file with flat response from 10 to 200 hz at 0 db. I then load it in to REW and apply filters to it until i get the curve I am looking for. Then I save that as a JPEG and use SPL Trace to convert it to a text file. I guess it would be simpler just to write house curves in Notepad but I find it easier to draw it first and then convert to text. 

Jason


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