Response curve as target curve?

[Ominae]

I'm trying to match the response of my speakers on each side. I've measured and EQ'd the left side speakers, now I'm trying to EQ the right side speakers to match (as much as possible). I saw that REW has the option to export a measurement as text, so I saved a measurement of my left side and used that as the target curve to EQ the right side. It's the same curve, but much higher decibel level on the graph (60db-90db for the original measurement versus 130db-160db for the target curve).

Is there a way to use a measured response as the target curve and keep it the same level as the original measurement? I tried searching the forum but didn't find an answer.

 

[Wayne A. Pflughaupt]

Not sure I get the question. A target curve is a slope in frequency response, not a hard dB level.

That said - welcome to the Forum!

Regards,
Wayne

 

[Ominae]

Maybe I'm not explaining it correctly. I'll try to clarify.

I've taken a measurement of the speakers on the left and exported it as a text file. I'm trying to input that file as a target curve so I can match the response of the speakers on the right to those on the left.

The issue I'm having is with importing that text file into REW. The response curve is the same, but it shows at a much higher decibel level on the EQ graph. When I exported the measurement (as a .txt file), it ranged from from 60 to 90 decibels. When I import it as a target curve and then go to the EQ window in REW, it shows up as a target curve, but it shows it on the graph as ranging from 130 to 160 decibels. So if I take a measurement of the speakers on the right and try to match them against this new target curve, REW is trying to do this at a decibel level that is twice the original.

So my question is: Is there a way to take a measurement, export it as a .txt file, then use it as a target curve at the original measurements decibel levels? I've tried to do this a few times but it always put the target curve at double the original db levels.

 

[John Mulcahy]

I guess you are loading it as a House Curve and using a flat target response? The target curve has an associated target level, typically around 75 dB, so the data in your house curve will be adding to that - if your measurement was around 70 dB and the target level was 75 dB the result would be around 145 dB. You could change the target level to be somewhere around 0 to offset it that way, but a better option would be to apply an offset to your measurement to bring centre it around 0 dB before saving it as text, using the graph controls and Add offset to data.

As an aside, applying EQ above a couple of hundred Hz is a risky business that can easily do more harm than good, responses can vary a lot over short distances so filters you apply may have a very different effect than you expect just a short distance away from the measurement point. If you do apply EQ at higher frequencies best keeping the filter Q values low and typically best applying the same EQ to both channels (somewhat counter to what you are attempting) as our brains are pretty good at distinguishing the direct sound from the speaker from the contribution of the rooms' reflections (which are included in your measurement) so what you hear is often not what you see on the measurement.

 

[Ominae]

Thanks for the response, John.

This is for the system installed in my vehicle. The mounting locations of the speakers make it impossible to get the same response from my left and right speakers at the listening position. It is causing a shift in the soundstage at certain frequencies. To counter this I am trying to match the response of the left and right side speakers. It is a compromise, but probably the best I'm going to get in a car.