# Help setting Target Level for REW Equalization



## byancey (Jun 29, 2014)

I've got a Behringer 1124p being delivered this Friday and I've been playing with the Equalization feature in REW to come up with a reasonable set of filters to apply. I'm unsure of what guidelines if any I need to take into consideration when setting the target level for the house curve. The target level set by REW seems too high to me and the predicted result is not significantly different than the measured curve. Attempting to match the target level to the average or low point of the original curve results in a predicted curve that follows the house curve fairly well, and tends to use relatively few filters. If I go well below the original curve, I start getting warnings from REW that a significant percentage of my house curve is below the original curve and more filters are used, but I can get a pretty flat predicted curve that follows the house curve very closely.

I've included 5 plots below that start at the level recommended by REW and work their way down to well below the curve. If I were looking only at how well the resulting predicted output follows the house curve, I would simply pick the lowest target, but I assume it's not that simple. Any suggestions on guidelines to take into consideration when setting the target level would be greatly appreciated as well thoughts on which approach below would yield the best real-world results.

Thanks!


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## EarlK (Jan 1, 2010)

As long as you can make up the gain ( from excessive EQ cutting ) to balance sub to mains , almost any of the target EQ's can be made to work ( excluding the first ) .

I'd go with #3 as a target ( it's close enough & uses fewer filters ) / though #4 is a bit better looking .

I would not auto EQ unless the sub-woofers ( or AVR's ) low-pass filter is engaged . I can't tell if it is or is not ( due to the clipped pictures ) .


:sn:


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## byancey (Jun 29, 2014)

I have LFE set to 80Hz in the crossover menu on my Denon AVR...it's a confusing location for that setting, but I believe it's the LPF as opposed to the crossovers for R/L, C, and surround found in that same menu.


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

Judging from the looks of you target curve, it looks like you’ve seen my “Minimal EQ” article?

It looks like REW isn’t recommending any boosting filters, did you enable that function in the EQ window?




> ...but I can get a pretty flat predicted curve that follows the house curve very closely.
> 
> If I were looking only at how well the resulting predicted output follows the house curve, I would simply pick the lowest target...


It isn’t necessary for the curve to perfectly track the target. The deviations between graphs #4 and #5, for instance, would not be audible.

Looks like you dropped the target a full 6 dB between the first and second graphs. I’d suggest only dropping it 3 dB instead, to better center the target between the peaks and depressions.

Among the posted graphs I’d go with #2. I’d add a filter to lift the area between 30-40 Hz, and possibly eliminate filters #1 and #5. They’re so close to your crossover frequency they’ll probably get blown out by the main speakers anyway.

Regards, 
Wayne


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## byancey (Jun 29, 2014)

Wayne A. Pflughaupt said:


> Judging from the looks of you target curve, it looks like you’ve seen my “Minimal EQ” article?


Yep. Great article. 



> It looks like REW isn’t recommending any boosting filters, did you enable that function in the EQ window?


I think I missed that setting. I did notice that REW wasn't boosting anywhere and was curious about that. I'll track that setting down and enable it. 



> Among the posted graph I’d go with #2. I’d add a filter to lift the area between 30-40 Hz, and possibly eliminate filters #1 and #5. They’re so close to your crossover frequency they’ll probably get blown out by the main speakers anyway.
> 
> Regards,
> Wayne


Thanks for the input. I'll take a look at that this evening. Can't actually apply any of this until tomorrow when my BFD arrives. 

Thanks.


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## byancey (Jun 29, 2014)

*Blending EQ SW with my mains+*

My BFD is out for delivery today, so I should be able to play with some equalization and take some actual measurements of the results this weekend. With some possible EQ curves behind me, I've started to take a closer look at how to go about blending my mains with my Equalized subs.

Keeping in mind that I don't actually have my Equalizer yet, here's the approach I took.

Using the REW check balance feature I set the levels so that both subs playing together were roughly equivalent to L+R playing together (~-18dB FS). I did not consider the center or surround channels for this measurement.
Took a sweep measurement from 15 to 200 Hz of the mains together.
Took a sweep measurements from 15 to 200 Hz of the subs together.
Equalized the sub curve from step 3 and compared the resulting levels around my crossover frequency to the measurements from step 2. Used this information to determine how much to increase the output level of the subs (about +7 dB in this example).
Adjusted the output using the volume settings on the subs to provide the needed boost from step 4.
Took another sweep measurement of the boosted sub and applied the same filters from step 3.

A graph with the resulting equalized subwoofer curve overlayed (dotted green) on the curves for the mains at normal levels and the subs at +7 dB boosted levels is attached. Based on this graph, it actually looks like 90 Hz may be a better crossover point than 80 Hz...or possibly crossover the mains at 70 Hz (though I think may AVR may only allow 60 or 80 in that range) and apply the LPF starting at 90 Hz.

Is my approach to determining how to blend the subs and mains sound? How about my conclusions regarding crossover and LPF? Any recommendations based on the attached graph? 

Thanks!


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## byancey (Jun 29, 2014)

*Re: Blending EQ SW with my mains+*



byancey said:


> My BFD is out for delivery today, so I should be able to play with some equalization and take some actual measurements of the results this weekend. With some possible EQ curves behind me, I've started to take a closer look at how to go about blending my mains with my Equalized subs.
> 
> Keeping in mind that I don't actually have my Equalizer yet, here's the approach I took.
> 
> ...


Answering at least one of my own questions based on my experience this evening. Setting the subwoofer level based on the level of the L+R playing together resulted in far too much bass. Instead I measured L and R separately, average those two curves, and then used this as the basis for setting the subwoofer level. This gave a much more balanced result.

After applying EQ and taking actual measurements with the BFD in line, I also ended up extending my house curve out to 100 Hz and adjusting the LPF for the sub and crossover for the mains to match. That spike in the mains between 70 dB and 90 dB levels out a bit around 100 Hz and made a much more natural transition from the subs to the mains.


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