How to best use REW to balance drivers

properly gate results

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Be sure you move the speaker at least the distance that the gate covers to remove any reflections, and be aware of the mic and its stand. Position the mic head pointing directly at the driver at about 12 inches or less and try and keep the stand out of the way. Be sure you're on-axis, as even small off-axis positions may offer poorer results. In fact an off-axis measurement is also useful.

Remember that gating puts a limit on the lowest frequency and the resolution of the response. For example, if you were trying to limit reflections from surfaces 1 meter away, you would use a minimum 6msec gate (d=(time*speed)/2)=(6msec*344m/sec)/2, but this would limit the lowest frequency of usable response information to ~167Hz (freq=1/period)=(1/gate time). So, you could select a left gate of 1msec and a right gate of 5 msec. You can go less for tweeters and midrange. I seem to remember using a 3 msec gate last time I was testing my tweeters for a test.

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. The popup will show the gate window and frequency resolution for you, so you don't need to do the math on that. 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. Of course, shut off any smoothing.

brucek

I will upload it to the web site

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I looked at your new mdat (taken with calibration files) and I would say that the wiring of the JBL in the plot called Full range would be your best method.

The response called FR rev polarity shows a cancellation that would indicate the woofer and JBL are out of phase at the crossover.

If two signals are in phase as they cross (just like a subwoofer and mains at the crossover), the resulting signal should be about 6dB higher. If I look at your mdat and do some gating, and show them with an expanded axis at the crossover of the woofer and mid JBL driver, I would say the response that you call Full Range (green trace in the first jpg below) could be considered a classic 6dB mix, and the correct polarity. The second jpg shows a dip around the crossover (blue trace) and I would consider it the incorrect wiring of the driver.

Correct crossover

Incorrect crossover

brucek