# How do I apply a "house curve" using REW and my DSP1124P??



## deepstang

Thanks to everyone's help I was able to have REW automatically apply and transfer a 4 point adjusted graph to my DSP1124P. I have been searching and can't figure out how to get the data in REW to have a "house curve" applied to my room. I found this interesting article, but still can't figure out how to load a house curve to REW, and in return have my room tuned as such. Thanks!

http://www.stephenmacmillan.com/ht/tips.htm


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## deepstang

OK, the write ups and directions here are amazing; however, it is funny how in all the instructions finding a simple answer can be a bit tricky. I saw several posts on House Curves, and read all the pages possible; however, it is not spelled out on exactly what to do.

It seems that I would need to find a data file that has the house curve numbers/data, save that and load that under the HOUSE CURVE screen in REW. I am not experineced enough to randomly derive these numbers and enter a house curve.

When I checked the box for "logarathmic interpolation", it did not seem to do anything. I think it is necessary for me to have the data file loaded for some type of house curve; however, i can not find a download of that data. 

Can someone please help me. Thanks!


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## JohnM

It is just a text file, as described in the help. Each frequency and SPL offset pair goes on a separate line.


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## Wayne A. Pflughaupt

> It seems that I would need to find a data file that has the house curve numbers/data, save that and load that under the HOUSE CURVE screen in REW. I am not experineced enough to randomly derive these numbers and enter a house curve.


Did you see these two? They descibe how to determine the house curve you need.

House Curve: What it is, why you need it, how to do it
On Minimal EQ, Target Levels, and a Hard-Knee House Curve




> When I checked the box for "logarathmic interpolation", it did not seem to do anything. I think it is necessary for me to have the data file loaded for some type of house curve; however, i can not find a download of that data.


The interpolation function facilitates a hard knee house curve. A simple two-line TXT file (as described in the Help Files link John provided) will suffice; there’s no longer any need to use all those values mentioned in the second article (Post #4) to “create” the flat-line Target. The “logarithmic interpolation” function automatically “flattens” the Target Curve to give a hard knee curve. So you could opt for a hard knee curve using the “logarithmic interpolation” function, or a standard house curve by not using the function.

Regards,
Wayne


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## deepstang

Thanks Wayne. I saw 1 article; however, the other one was new to me.

For anyone reading this in hopes of trying to apply a house curve using REW, here is what this noob learned thus far. First off, stop being scared and asking a ton of questions and just open "NOTEPAD" (if you have windows) and start off by typing in:

*20 6
80 0*

Once these simple numbers are entered in Notepad, save it (as a .txt file) and than under the ROOM CURVE screen (in the "Settings" tab (_has the symbol of a screwdriver and wrench in an "X"_)), click the BROWSE button and select the .TXT file you just made. 

As stated in the House Curve description in REW, this will basically give a target goal of a +6db boost starting at 20Hz and slope all the way to 80Hz ("0" designating no boost at 80Hz). When doing this 2 point method it is crucial to check that *"Use logarithmic interpolation"* box. 

I actually tried entering hard numbers in 5 to 10 frequency intervals; however, after multiple attempts it seems that using the "logarithmic interpolation" box and 2 points has the best result. I varied/tested the frequencies by maybe reducing or increasing the value at 20Hz. See what works best for you. 

Consider this my "Room Curve for Dummies" Cliff Notes version.


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## Wayne A. Pflughaupt

Well put Stang. :T

As noted in the articles, your room might need a different boost value than 6 dB. Also if you find that leveling at 20 Hz doesn’t sound good, try another value between 25-30 Hz.

Regards,
Wayne


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## tcarcio

Hey Guy's, I got a question. I don't have a laptop so no rew but I did check my house curve with the sinewaves like Wayne described and my lower feq's are louder then my upper ones. As a matter of fact the difference is that 30hz is 11db louder then 80hz. I cant cut enough to even them out so what would you do for this scenario?


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## Wayne A. Pflughaupt

REW is merely a measurement platform. It does nothing to compensate for differences in the two tones. If you don’t have REW, you can always use something like 1/6-octave sine waves plotted on graph paper or the spreadsheet program discussed in the BFD Guide. 


> I cant cut enough to even them out so what would you do for this scenario?


You aren’t _supposed_ to even them out. That would be _flat_ response, not a house curve. The object is that the high and low frequency tones should _sound like_ they are the same level.

Regardless, evening them out or adjusting so that they sound the same typically requires equalization.

Regards,
Wayne


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## tcarcio

I thought that you need a fairly flat response to start with and then do the sine wave measurements in order to get the info for the house curve?


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## Wayne A. Pflughaupt

Well, you do need to make sure that the two test tones are not located in a room peak or null, but it’s not necessarily a requirement to first flatten response. It may be that your unequalized response plays right in to the needed house curve for instance (mine does). In that case it’d be silly to first flatten and then induce the curve.

Of with course some response curves it’s best to first flatten response. It’s best to get a reading before equalization begins.

Regards,
Wayne


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## tcarcio

Thanks Wayne, I plan on running some tests tommorrow. I do have a problem I need to figure out as even with my sub off and the crossover set to 80hz I am still getting frequency readout on my mains below that. I know I will get some but I am getting strong readings in the 30-50hz range so I don't know whats going on.:dontknow:


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## Wayne A. Pflughaupt

Well, the crossover isn’t a brick wall. You can always expect some bass below the crossover point, but if it seems to be excessive, there could be lots of reasons for it:

* Speakers set to “large” in the receiver’s menu.
* Large main speakers with strong bass output (i.e., still putting out lots of bass despite having the lows filtered).
* Receiver’s crossover only works in digital mode (i.e. 5.1).

Regards,
Wayne


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## tcarcio

Well seeing how the only thing I have changed recently is my mains and they are big speakers, B+W 801's, It has to be the reason. Strange though, I would think the reciever cutting out the low freaks would just not allow the speaker to see them, especially if the crossover is set to 80hz and the speaker still see's freaks in the 30hz range.Doesn't seem to make sense. I will recheck my settings again just to make sure I have them set correctly.....Thanks Wayne.:T


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## Wayne A. Pflughaupt

Well, the crossover only reduces the signal electrically. If the speakers have enough acoustic output down there, you can still get a lot of bass from them.

A good way to see what’s happening, turn off the crossover and take a sine wave SPL reading at 40 Hz, which is one octave below your crossover frequency. Engage the crossover, and take another reading. Assuming the crossover has a 24 dB/octave slope, the second reading should be about that much lower.

Regards,
Wayne


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## tcarcio

I learn something new everyday here it seems. I will try that test and see how it comes out. I am running the sms 1 crossover with a 24db slope so that won't be a problem.


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## tcarcio

Deepstang, I hope you don't mind me useing your thread to ask some questions but since it is on the same subject I didn't think you would mind. Wayne, I ran the tones and for what it's worth my problem is a null. It is at 80hz, go figure, so I need to figure out what to do about it. I am limited with sub placement since I am running the DTS-10 so I hope a small move will help. Funny I just assumed, yes I know, that with a good readout from my sms that I was OK. :rolleyesno:


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## Wayne A. Pflughaupt

Is it a true null or just a depression? Most depressions can be equalized. If so you can eliminate it via equalization, then re-do the test.

Regards,
Wayne


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## tcarcio

Well seeing that the tone just about completley dissapears from the listening pos, I would think it's a null. The difference in spl readings is over 10db. So I don't think I could eq that or even would want to.


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## Wayne A. Pflughaupt

How did you determine that the 80 Hz tone is in a null?

Regards,
Wayne


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## tcarcio

Very low sound pressure levels at the LP. If you walk around my room while the 80hz tone is playing it is very loud until you go to the LP and then it just about dissapears.


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## Wayne A. Pflughaupt

And you don't get that with the lower tone?

Regards,
Wayne


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## tcarcio

No. The lower tone comes in loud and clear. I have been moving the sub around to the only places really available and I got improvement but not what I had hoped for.:rolleyesno: I am thinking of closeing in the half open wall but I am not sure how much improvement that would be for the money it would cost.


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## Wayne A. Pflughaupt

What do you get with tones at say, 90 and 100 Hz?

Regards,
Wayne


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## tcarcio

I only tried 100hz and it was louder then 80 but not by alot, maybe 5db or so.


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## Wayne A. Pflughaupt

I suggest getting a baseline reading, either with REW or 1/6-octave sine waves plotted on graph paper or the Excel program available in the BFD Guide, to see exactly where the null is, and how bad it is.



tcarcio said:


> Well seeing that the tone just about completley dissapears from the listening pos, I would think it's a null. The difference in spl readings is over 10db. So I don't think I could eq that or even would want to.


It would only be for the purpose of performing the dual tone test. Once you established the differential (dB slope) between the upper and lower tone, and create and load a house curve file into REW, you could remove that equalizing and proceed with normal measuring and equalizing.

Regards,
Wayne


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## tcarcio

Well moving the sub helped but my lower freq is still 4db louder then my crossover point. Now if it was reversed I know the house curve would be 4db from low freq to high but since it is louder at the lower freq do I boost the higher freq and cut the lower to creat the curve?????


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## Wayne A. Pflughaupt

> do I boost the higher freq and cut the lower to creat the curve?????


The object is to have both the lower and higher tone _sound like _they are at the same level. When that is achieved, the lower tone will _measure _louder than the upper. The SPL differential between the upper and lower tone is your house curve slope.

Regards,
Wayne


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