# How do I use target settings?



## ermesy (Jun 11, 2013)

I'm having a lot of difficulty in understanding the Target Settings window in REW 5.0.in trying to equalise my sub and floor standing mains using a miniDSP with the ADV 2.1 plugin. I want to set the cutoff for the sub at 75Hz but what do the "LF Cutoff", "LF Rise Start", "HF Fall Start", etc. mean and, more importantly, can anyone suggest what values they should be? I've read the REW Help topic but can't make head or tail of it!
According to a miniDSP help file I have, when equalising the sub only, I should set the "Speaker Type" to none (the help file might be a screen shot from an older version of REW as it doesn't display anything else other than the Target Level drop down box). Should I be selecting Subwoofer and, if so, what values should I be using for "LF Cutoff', LF Rise End", "LF Rise Start" and so on? If selecting "None", do I need to enter any values in the "Rise End", "Rise Start", etc. fields. And the same question applies when I select Full Range when I'm trying to equalise the mains. 
I've looked in the "Equaliser" section of Preferences as I know that's where the default settings are set but it still doesn't help me understand how to
use the settings sensibly to get the best results. 
BTW, I only what to equalise up to 1000Hz as I believe that beyond that there's not much REW can do - am I right in thinking that? So basically I'm looking to apply EQ from 20Hz to 1000Hz. 

Thanks for your help.


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## JohnM (Apr 11, 2006)

The idea of the target settings is to tell REW what you expect or want the response to look like, so it knows what to aim for when applying EQ. The first selection is what kind of speaker the measurement is from. If it's a Full Range speaker the basic target is flat. If it's from a Bass Limited speaker the target has low frequencies rolled off to include the effect of a bass management filter, then the Crossover setting lets you tell REW how steep the bass management filter is and what frequency it is set to. Same for Subwoofer, except the high frequencies are rolled off.

For Subwoofers and Full Range speakers the 'LF Cutoff' and 'LF Slope' settings also come into play. They are to allow for the fact that although we might like to have speakers or subs that are flat right down to 0 Hz, in practice they have a lower limit so it is better for the target to reflect that. For a typical 'Full Range' speaker that might be 40 Hz, for a typical sub it might be 20 - 30 Hz. You can usually see from the measurement where it is rolling off and adjust these settings for the target until it matches.

The LF rise and HF fall settings are there to allow a house curve to be superimposed on the response, the LF rise is typically used to have bass rising as frequency gets lower while the HF fall is used to reflect the downward tilt in HF for most listening position speaker measurements.

Finally the target level lets you move the whole target response up or down until it sits in the right place relative to your measurement. When the target is right the bits that go above it are the peaks you want to tame and it usually runs more or less through the middle of the measurement.

REW can apply filters anywhere across the band, but it is usually best to limit filters to low frequencies (less than 200 Hz or so) unless you are compensating for some general characteristic in the speakers (an example might be a dip in the mid range or a bit too much HF) - that is using EQ as a fancy tone control.


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## nathan_h (Feb 19, 2009)

ermesy said:


> I'm having a lot of difficulty in understanding the Target Settings window in REW 5.0.in trying to equalise my sub and floor standing mains using a miniDSP with the ADV 2.1 plugin. I want to set the cutoff for the sub at 75Hz but what do the "LF Cutoff", "LF Rise Start", "HF Fall Start", etc. mean and, more importantly, can anyone suggest what values they should be? I've read the REW Help topic but can't make head or tail of it!
> According to a miniDSP help file I have, when equalising the sub only, I should set the "Speaker Type" to none (the help file might be a screen shot from an older version of REW as it doesn't display anything else other than the Target Level drop down box). Should I be selecting Subwoofer and, if so, what values should I be using for "LF Cutoff', LF Rise End", "LF Rise Start" and so on? If selecting "None", do I need to enter any values in the "Rise End", "Rise Start", etc. fields. And the same question applies when I select Full Range when I'm trying to equalise the mains.
> I've looked in the "Equaliser" section of Preferences as I know that's where the default settings are set but it still doesn't help me understand how to
> use the settings sensibly to get the best results.
> ...


I asked the same question on the minidsp forum and the answer was to choose "none" for speaker type, to avoid unintended consequences of REW's default approach to a particular sub making assumptions that might not be correct in a situation where there is no pre-pro or receiver -- apparently since I'd be setting crossovers (hi pass filter for the stereo mains, low pass filter for the sub) in the minidsp interface itself.

I too am flummoxed by the OTHER choices in the REW interface at this point, and have asked about that, there, but have not got a response, yet. I could foresee where their approach was the ideal scenario with the version of REW they used when writing their guide, but maybe the current version of REW, which has more user changeable controls on that screen, might not be "correct" (i.e., what they expect) when used this way.

It certainly flummoxed me when trying to figure out how to use the REW auto generation of EQ correction filters for the high frequency mains, and I just decided to run my mains without any EQ, only using the minidsp for crossover, in the case of the mains. Sub is still getting EQ-ed, though I did have to turn it WAAAY up, due to how REW set the recommended target volume perhaps? for smoothest response. Luckily I had the headroom to spare.

In any event, it is a very cool combo. And you don't have to follow the minidsp instructions. Try it the other way and see how it measures and sounds.


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## ermesy (Jun 11, 2013)

Thanks Nathan - and a very big (albeit belated) thanks to John for his reply. 
Re your comments about miniDSP I made the mistake of paying far too much attention to their instructions whereas I should've come back here much sooner. Since John's reply, I've been experimenting a lot with the target settings and have learned an absolute truckload about improving the response - it's been a revelation!
So now I ignore miniDSP's instructions and set the speaker type to sub and tweak all the settings to get the smoothest response I can and I'm still finding ways to improve the response. Same goes for EQing my mains. The good thing about the miniDSP is that, with the input PEQ blocks and channel 3 and 4 output blocks, you've got 12 filters per channel to tweak your mains response so don't be afraid to utilise that functionality - after all, you paid for it! I limit my mains EQ attempts from 100 to 800Hz though admittedly the sonic results are not nearly as obvious as for the 20 - 100Hz range I'm currently experimenting with my sub (I have a peak the size of Mt Everest at 40Hz in my room - but not anymore!)
My advice to anyone else who's having difficulties in this area - ignore miniDSP's instructions and come here for help - you'll learn more in a few days than months following miniDSP's advice.

Cheers.


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## subterFUSE (May 10, 2014)

The most detailed REW tutorials I have read are in the car audio forums like DIYmobileaudio.


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## nathan_h (Feb 19, 2009)

ermesy said:


> Thanks Nathan - and a very big (albeit belated) thanks to John for his reply.
> Re your comments about miniDSP I made the mistake of paying far too much attention to their instructions whereas I should've come back here much sooner. Since John's reply, I've been experimenting a lot with the target settings and have learned an absolute truckload about improving the response - it's been a revelation!
> So now I ignore miniDSP's instructions and set the speaker type to sub and tweak all the settings to get the smoothest response I can and I'm still finding ways to improve the response. Same goes for EQing my mains. The good thing about the miniDSP is that, with the input PEQ blocks and channel 3 and 4 output blocks, you've got 12 filters per channel to tweak your mains response so don't be afraid to utilise that functionality - after all, you paid for it! I limit my mains EQ attempts from 100 to 800Hz though admittedly the sonic results are not nearly as obvious as for the 20 - 100Hz range I'm currently experimenting with my sub (I have a peak the size of Mt Everest at 40Hz in my room - but not anymore!)
> My advice to anyone else who's having difficulties in this area - ignore miniDSP's instructions and come here for help - you'll learn more in a few days than months following miniDSP's advice.
> ...


Cool. Thanks for the perspective.



subterFUSE said:


> The most detailed REW tutorials I have read are in the car audio forums like DIYmobileaudio.


Any in particular you'd recommend?


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## subterFUSE (May 10, 2014)

nathan_h said:


> Any in particular you'd recommend?


Start with this one: First Timers Guide To Measurement


I'll find some more and post later.


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## nathan_h (Feb 19, 2009)

subterFUSE said:


> Start with this one: First Timers Guide To Measurement
> 
> 
> I'll find some more and post later.


Thanks for the link. Reading now.

EDIT/Update: Good stuff for how to measure. Most interesting that they don't do the SPL calibration piece, first, but maybe they are assuming that info is in the mic profile/correction file?

I'm hoping to find something like that walk through for creating correction filters, especially related to these:


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

ermesy said:


> The good thing about the miniDSP is that, with the input PEQ blocks and channel 3 and 4 output blocks, you've got 12 filters per channel to tweak your mains response so don't be afraid to utilise that functionality - after all, you paid for it!


Actually, you should be afraid! Don’t get caught up trying to achieve a good-looking graph. The goal when equalizing the main speakers is an _audible_ improvement. An audible improvement won’t necessary “look” the best on a graph. You can’t use the same kind of drastic filtering on the main speakers that we use with subwoofers. Typically adjustments of a few dB are about all you can reasonably accomplish with the mains. Smoothing the graph to 1/3- or 1/6-octave before equalizing is a good idea, as this gives you a graph that visually resembles what you’re actually hearing and will help resist the inclination to over-equalize. If you haven’t already I’d suggest taking a look at my “Minimal EQ” article.

The goal isn’t to correct every little ripple in response you see on the graph, but to correct the broader ones, as they are the most audible. As such mains filtering should be more along the lines of broader adjustments. Typically that means filters no less than 1/4 – 1/3 octave wide. Typically 3-4 filters should be sufficient. If you think you need more than that I’d suggest perhaps the speakers are severely deficient.

The green trace in the graph below is a good example. Dropping the broad area between 500 and 2 kHz would make an audible improvement, as would lifting the area between 2 and 10 kHz. The ragged area above 3 kHz in the red trace is an example of “severely deficient.”











Here's a "case study" thread of a successful full-range EQ effort. Ignore the suggestions that the mains can't be equalized, and upright mic orientation for measurement.

Spridle’s Experiment

Regards, 
Wayne


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## nathan_h (Feb 19, 2009)

Wayne A. Pflughaupt said:


> Actually, you should be afraid! Don’t get caught up trying to achieve a good-looking graph. The goal when equalizing the main speakers is an _audible_ improvement. An audible improvement won’t necessary “look” the best on a graph. You can’t use the same kind of drastic filtering on the main speakers that we use with subwoofers. Typically adjustments of a few dB are about all you can reasonably accomplish with the mains. Smoothing the graph to 1/3- or 1/6-octave before equalizing is a good idea, as this gives you a graph that visually resembles what you’re actually hearing and will help resist the inclination to over-equalize. If you haven’t already I’d suggest taking a look at my “Minimal EQ” article.
> 
> The goal isn’t to correct every little ripple in response you see on the graph, but to correct the broader ones, as they are the most audible. As such mains filtering should be more along the lines of broader adjustments. Typically that means filters no less than 1/4 – 1/3 octave wide. Typically 3-4 filters should be sufficient. If you think you need more than that I’d suggest perhaps the speakers are severely deficient.
> 
> ...


Thanks for pointing this out. I thought I was crazy for preferring the sound of my mains WITHOUT EQ versus the default recommendation from REW -- which worked great on the sub, but sounded off on the mains.

So for now, I am using the minidsp for crossover (between sub and mains) and for EQ for the sub, and that's it.

There is still room for improvement, I think, and that's probably due to user error. Once I learn more, I may revisit the mains and see if there are any humps in the 100 to 200z range and try to bring those down, but other than that, I'll likely not touch them much.

(This is a 2.1 setup.)


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## ermesy (Jun 11, 2013)

Hi Wayne - after a bit of an absence I came back looking for help with an Impulse Response problem I'm suddenly having and revisited this thread. Thanks for your input as I had no idea about smoothing the graph response to help with EQing. Sadly I have fallen into the trap of focussing on a good measurement and expecting a good audible response (not for the first time!) Anyway, if I can get around my current IR problem, I'll certainly take on board your advice.
Cheers.


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## Phillips (Aug 12, 2011)

I managed to do a near field measurement of my speakers, so I can see the response of the speaker

This showed the crossovers of my speakers, this shows in my in room response although not as prominent.

I wonder if I can EQ the crossover dips?

Also with a 6th smoothing what is the tolerance say +-5db?


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## ermesy (Jun 11, 2013)

Re EQing the xover dips - I think the preferred option is, if possible, to first try adjusting the xover slopes. miniDSP allows adjustment between 6db/octave to 48 db/octave. But then I'm by no means an expert on this so maybe someone more knowledgeable could help? 
No idea about your second question, Phillips, sorry!


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