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Discussion Starter #1
Well finally I was able to figure out how to properly calibrate my soundcard and mic, to have a refrence point to start with measurements. Then I added some room treatment and these are the results, I would like to thank all who gave advice.
 

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REW Author
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I suspect that was due to using a 75 dB target level? For the data that was captured 85 dB would probably have been a more appropriate target, REW will estimate a suitable level if you use the 'Set Target Level' feature in the target shape panel of the EQ window.
 

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Discussion Starter #4
John,
I am fairly new at this and barley know what I am doing, I thought you wanted a target value of 75db? Why would I want REW to estimate any values for me? What would be the point of that? What should my target value be? I think maybe I got something wrong and will have to start over.
 

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The target defines a shape the response should be aiming to achieve, which includes allowance for the capabilities of the speakers - for example, if the speakers can only manage 50 Hz there's no point having a target that is flat to 10 Hz as the speakers simply couldn't deliver it. The Target Settings panel in the EQ window let's you configure those aspects of the shape of the curve, like the low frequency limit of the speaker.

Once you have the shape of the curve right, it needs to be set at the right level to tie up with the level of your measurement. EQ isn't a volume control, so if (for example) your measurement sits mostly around 85 dB and you used a target curve which had a level set at 75 dB you would be trying to use EQ filters to drag the whole response down by 10 dB - that's the job of the volume control! To allow for the fact that measurements will vary in level there is a 'Target Level' in the Target Settings panel. You can adjust that manually until the target shape lines up at around the average level of your measurement, or you can ask REW to adjust it for you using the 'Set Target Level' action. Once the level of the target looks about right then go ahead with the EQ.
 

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Discussion Starter #6
Ok John,
That makes sense and I understand that. Now let me ask you this, as you pointed out most of my measurement sits in the 85db range. Why is that? What is the deciding factor in where the level sits? Would that be the volume control or something else? Also being what it is are you saying I should move my target to 85db and go from there? That would seem to be the right thing to do in my mind? Thanks.

Jay
 

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Yes, just the volume control. You can set the target level to suit the measurements you have, and you could also make the measurements at a lower volume and use a lower target level to suit - 85 dB is a bit loud when you are making many measurements. The level doesn't change the shape of the result (unless it is very loud or very quiet, when distortion and background noise intrude respectively), just how far up or down the graph the curve sits.
 
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