RE: How to measure Magneplanars - triamp 16:13:02 03/24/21 (0)
 RE: How to measure Magneplanars - emailtim 11:56:25 03/24/21 (0)
 RE: How to measure Magneplanars - andyr 03:53:18 03/24/21 (1)

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 RE: How to measure Magneplanars - triamp 16:13:02 03/24/21 (0)
 RE: How to measure Magneplanars - emailtim 11:56:25 03/24/21 (0)
 RE: How to measure Magneplanars - andyr 03:53:18 03/24/21 (1)
 RE: How to measure Magneplaners - dumpingground 07:11:51 03/24/21 (0)

Be advised that using a USB mic and USB DAC has the downside of having 2 different clocks which are not in sync. The next best thing is to use a single soundcard for both the mic and the DAC so the clocks are in sync. The downside is it costs more is more complex. You can also Master/slave clock both devices if they provide such features, but again, it adds more complexity and expense.

Since you said you do NOT have a PC source in your signal chain, you will have to follow a different procedure than many here. You will have to use REW to create some sweep wav files with timing chirps and then burn the REW generated wav files to a CD so you can play them on your [CD|multi-disk] player. The sweeps need to be of the same sample rate as your intended measurement sample rates (e.g. limited to 48kHz for the UMIK-1 so you would need a DVD player). It also requires the reference timing channel to be able to play high frequencies so if you are going to measure a sub by itself on the left channel, the timing chip should be on the right channel that is capable of a HF output.

This allows you to measure a playback system without physically being attached to it.

If you intend to measure each driver independently, you will have to protect each driver and only send it a signal within its usable range. This can be done in a variety of ways depending on how you are measuring.

If you measure with a higher sample rate, you will get a better HF measurement if your mic and playback chain is capable of handing the higher sample rates.

You can get a calibrated mic from Cross-Spectrum Labs or they will calibrate your mic if you already have one. They will generate files readable by REW. Note, they are slow. My experience has been that mics are off the most at low and high frequencies.

As for XO's. That is another issue. You need to level set your drivers first because the XO point changes as the magnitude of the individual drivers change.
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2022/03/30 Historical Records CENSORED

I would caution folks against spending too much time fiddling with EQ in a single session, some kind of aural confusion or fatigue sets in and your ability to critically judge the sound of the frequency range you are working to balance can elude you. Better to come at it another day with "fresh ears."

I've gotten what I think are very good results with the DEQX, to which I add some manually set parametric EQ points which I **think** help compensate for room modes, but which may actually be just personal preference.

Here is a plot of the correction filters my DEQX designed, please note that this is also compensating for differing gain levels in the amplifiers that drive the low, mid and tweeter drivers of my MG 3.6

Results for both MG 3.6 speakers were close to each other as you can see from the different colors in the plot.

Very likely that some room correction got "built in" to the woofer filter. I know I have a strong room mode at 50 Hz and you can see a dip in filter response at 50 Hz.

Note that these are NOT frequency response graphs- they are the "correction filters" my MG 3.6's need to bring them close to + / - 1 dB from ~100 Hz to 20,000

Note the increasing level of boost above about 15 kHz. I can't hear much above 12 kHz so I don't care about that, really. Maybe the tweeters do, but so far they have not burned our nor have fuses opened, so I am OK with that boost.