# How's my house curve?



## skool (Mar 9, 2009)

Hi guys, I've just been following the REW forum and began to use REW software with my eD A2-300. I then began my journey in flattening my sub by purchasing an eQ.2. It works relatively well in my room. However, recently I noticed a thread of Wayne about house curve and it changes everything that I thought about a flat-sounding sub. Now, I understand why many people prefer to run their sub hot (2-5 db) rather than flat at 75 dB. Is this basically what Wayne called as "perceived flatness" rather than "measured flatness"? 

Is it bad to boost a center frequency in order to achieve a house curve? Or should we allow room gain affects that will resulted in a house curve? Looking at the REW graph of my sub, how's my house curve? Btw, I am running my sub ~3 dB hot.












Btw, this graph is taken at seating position with no eq applied.


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## brucek (Apr 11, 2006)

> Looking at the REW graph of my sub, how's my house curve? Btw, I am running my sub ~3 dB hot.


It's not good, I'm afraid. That's not a house curve. You have a peak between 30Hz and 40Hz at the expense of losing the precious signal below it. That 'hump' simply overwhelms the lower frequencies.

The first order of business in creating a house curve is to be sure you have the response that can accommodate what you'd like to do, and then create a house curve file. This then, offers you a target line to follow.

The house curve file can be as simple as asking for an 8dB rise from 80hz down to 30Hz. You have to be sure that at 30Hz that you have enough signal left to run flat down to your lower extension point (~22Hz in your case). It looks like you only have enough for about 5dB-8dB rise from 80Hz down to 30Hz (from your graph).

Look at the overlay graph below of a standard target compared against a +5dB house curve target. It starts to rise at 80Hz and ends 5dB higher at 30Hz. It does not drop off below that. If the sub dropped off below that, then the house curve chosen is too ambitious for the sub.

BTW. Post all graphs with a vertical scale of 45dB-105dB and a horizontal scale of 15Hz-200Hz. Make the size is 800 wide. Use the floppy icon in the lower left corner of your graph to save your graphs in that size.









brucek


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

skool said:


> Btw, this graph is taken at seating position with no eq applied.


Since you have an equalizer, why not show us an equalized graph?

Regards,
Wayne


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## skool (Mar 9, 2009)

Thank you guys for you replies. I am still learning about this. How exactly do you create a house curve file? Is it just a text file specifying the hump?



> BTW. Post all graphs with a vertical scale of 45dB-105dB and a horizontal scale of 15Hz-200Hz. Make the size is 800 wide. Use the floppy icon in the lower left corner of your graph to save your graphs in that size.


I will keep that in mind next time. Thanks.



> Since you have an equalizer, why not show us an equalized graph?


I will try it again tonight and post the result. However, given the limited band filter on the eQ.2 equalizer, I am afraid I will not able to achieve the ideal house curve. If you're not familiar with the eQ.2, it only has two band filter. One is from 10-50 Hz, and the other is from 50-100 Hz. Anyway, I can tame that 30-40 Hz with my first band as I've done it before, but wasn't sure about the house curve so I reset the eq. Also, do I need to disconnect the front speakers when measuring the sub's response?


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## brucek (Apr 11, 2006)

> How exactly do you create a house curve file?


It's a simple text file. You must have missed that section when you read REW HELP files.



> I can tame that 30-40 Hz with my first band as I've done it before


That's basically all you need. Draw a line on your graph above from 22Hz to 52Hz and that's your target.



> do I need to disconnect the front speakers when measuring the sub's response?


Yes, it's best to get your sub alone dialed into the best response. Then add the mains and re-measure and then adjust your subs phase to clear up the crossover area.

brucek


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## skool (Mar 9, 2009)

I got home a little late tonight, but managed to do some more REW testing. I finally bought the Y-Cable necessary to feed the mono right RCA output into the receiver. I am not sure if it makes a difference, but just wanted to be sure I'm not missing anything. House curve is applied. Anyway, here are the results:

Graph below is original frequency response remeasured:












Below is the graph after EQ is applied. It is relatively flat from 45 - 22 Hz. How does it looks?












Here's a graph with the main towers added. The sub is recalibrated and is running roughly 3 dB hot.


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## brucek (Apr 11, 2006)

> It is relatively flat from 45 - 22 Hz. How does it looks?


It looks very good. You have the right idea now.

But, your mains are offering you a peak between 60-120Hz that may be possible to lower with some movement in their positioning. It may not be audible - I don't know.

brucek


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## skool (Mar 9, 2009)

Yeah, I may have to reposition the towers a little more to fix that. It's just too bad my receiver doesn't have some form of auto calibration with eq built in so I can play with it a bit more. 

Bruce, thanks for your comments though.


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