First Response...doesn't look right

Depending on the number of drivers in your speaker, will determine how far away you do the measurement. A single driver would be in the 1"-3", so quite close.

But, if you have 2 drivers, you would need to determine where a proper mix/integration was realistic. Certainly not more than 12". Best to move the speaker as far away as possible from any boundaries.

The mic is pointed directly at the speaker (horizontal axis) and at 0 degrees. You can play with taking measures of horizontal off axis (30 deg.) too, to see how the off-axis distribution looks.

REW remains the same for taking the measurement, but once taken, then you can work with the impulse response to set an appropriate gate time depending on the frequencies you're measuring. Simply open the IR Windows pop-up and select a gate that you want and watch the impulse response to ensure it's appropriate (with respect to reflections), then select Apply Windows and your response graph will adjust to that gate time response plot. I've used a 1msec left window and a 5 msec right window quite successfully for 500-20000Hz measures. The popup will show the frequency resolution for you, so you don't need to do the math. You're trying to exclude reflections from any surfaces nearby. It could be as simple as the mic stand, but predominantly hard surfaces such as the floor.

So, a gate time of 5 msec would give you a reflection free time of about 0.86 meters. Remember the sound has to hit the boundary and bounce back. So, distance=(time*speed)/2 = (5msec*344m/sec)/2. Remember that a short gate time limits the lowest frequency you can get useful response information for. So 5 msec limits your lowest frequency to about 200Hz (freq=1/period).

So, for reflection free measurements where your closest boundary is 1 meter away, you could use a 5 or 6 msec gate and check your response fairly accurately without smoothing for a measure from maybe 500Hz-20000Hz. Then for the bandwidth below 500Hz, you could measure from 0-500Hz and extend your gate out.

If you wanted an overall full spectrum measure, you could use a wide gate and use smoothing. A bit less accurate, but suitable to take a wide general look.

brucek

I don't post here often, unless I am calibrating my system

Your dip at 200hz could also be due to the null from the front wall. This depends on how far you place the speaker from the front wall. The closer the speaker is to the front wall, the higher in frequency the null will be. For example, if your speaker is right up against the front wall such that the drivers are about 1.4' away from the wall, you will get a null around 200hz.

I generally, try to keep my speakers 4' or more from the front wall to minimize this effect.

Of course, i am unfamiliar with your speakers, so the problem could be something else. However, an easy test is to move the speaker further from the front wall for the purpose of testing. If the null moves down in frequency, then you know what is the main cause of the problem.

As per your tweeter's drop off, this might be due to the polar response of your tweeter. You might try toe-ing the speaker in towards the listening position to get closer to an on-axis FR.

Of course, an on axis near field measurement with the speaker away from boundaries could show if any problems might be due to the speaker design.