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I guess I just didnt see him change his slope (or maybe he tried), just lowered the crossover freq. But cabin rise was fighting against him.

Oh well, not curious anymore. Thanks SkizR. :D
no problem. i wouldnt bother with eq to far after the crossover unless the was an abnormal peak
 

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I'm pretty sure that's what cross spectrum sent me in the 3 cal files.
What Mic is it? Usually measurement mics are omnidirectional. One file is probably flat, one a-weighted, and one c-weighted

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It's the UMM6 USB. I got it from cross spectrum. They sent 3 cal files with it on a USB stick.
 

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What Mic is it? Usually measurement mics are omnidirectional. One file is probably flat, one a-weighted, and one c-weighted

Sent from my HTC6525LVW using Tapatalk

Cross Spectrum Labs sends On Axis, 45 degree and 90 degree off axis cal files. I have the same UMM6 and that's what they sent me.

High freq sounds tend to roll off when measuring off axis. The off axis cal file compensate for that.


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On/Off axis in regards to how you hold thd mic, or how the speaker is aiming?

I have a Dayton UMM, but not from Cross Spectrum so only the one cal file. Should I be pointing the tip of the mic in direction of the soundstage vs. Pointed up at the roof?
 

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On/Off axis in regards to how you hold thd mic, or how the speaker is aiming?

I have a Dayton UMM, but not from Cross Spectrum so only the one cal file. Should I be pointing the tip of the mic in direction of the soundstage vs. Pointed up at the roof?
The mic cal files are based on where the mic is aiming.


0 degree on-axis means the mic is pointed directly at the sound source.

45 degree means mic pointed 45 degrees off-axis.

90 degrees would be pointed perpendicular to the sound source.
 

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Cross Spectrum Labs sends On Axis, 45 degree and 90 degree off axis cal files. I have the same UMM6 and that's what they sent me.

High freq sounds tend to roll off when measuring off axis. The off axis cal file compensate for that.


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interesting. i always thought that it was omnidirectional
 

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interesting. i always thought that it was omnidirectional
Depends on frequency.

Most mics will have a high frequency rolloff based on directivity. That's why we get them calibrated. :D


Very similar to how all speakers eventually beam, depending on frequency.
 

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Yep. My UMM-6 came with 0, 45 and 90 cal files for "narrow band" and "1/3 octave" each. Taking a guess, using REW, I have 90 narrow band loaded as the cal file for tuning as Kyle demonstrated in the vids.


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And I used the 0 narrow so far for on axis like a few I have seen placing the mic around the headrest.

While sitting in the car (as I am a larger mass than other things in the car and I think I might make a sonic difference), I hold the mic at my mouth position, then left outer shoulder and then right.

But an Audio Pro told me to calibrate the dash drivers, tweeters in my situation (you might have mids in the dash).... from opposite sides of the driver I'm working on to get a better reading.

I think holding the mic, let alone moving it may introduce vibes and noise and kinda add things that I likely can ignore, but rather not include in the reading.
 

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I use the UMIK-1 and held it 90, 45 and 0 degrees. Measures the same. However, it does come with a 90 degree file to use with the NanoAVR.
 

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On/Off axis in regards to how you hold thd mic, or how the speaker is aiming?

I have a Dayton UMM, but not from Cross Spectrum so only the one cal file. Should I be pointing the tip of the mic in direction of the soundstage vs. Pointed up at the roof?
http://www.diymobileaudio.com/forum/how-articles-provided-our-members/163234-first-timers-guide-measuring-your-system.html

You can see how you're supposed to position the mic,it's usually facing the windscreen.That's the exact reason why you got the 45 and 90 degree calibration file as microphones get directional in the higher frequencies.They are to compensate for that as in the car you're not measuring on axis.
 

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Old post! I have a tuning question. After having everything time aligned, levels matched, and each side (l&r) eq’d to within 1 dB across the range, what do you do if the center image still pulls one way?
Adjust levels of independent drivers? Bandpass pink noise and further eq? I’ve read not to mess with time alignment once set. Any suggestions, thanks.
 

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Old post! I have a tuning question. After having everything time aligned, levels matched, and each side (l&r) eq’d to within 1 dB across the range, what do you do if the center image still pulls one way?
Adjust levels of independent drivers? Bandpass pink noise and further eq? I’ve read not to mess with time alignment once set. Any suggestions, thanks.
Tune by what sounds best. Period.

Isolate a set of drivers. So both midbass. Or both midrange. Or both tweeters.

If those drivers are playing 2k and down. Focus on moving image with time alignment and a little bit of level changing

If 2k and up. Its pretty level dependent.

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Tune by what sounds best. Period.

Isolate a set of drivers. So both midbass. Or both midrange. Or both tweeters.

If those drivers are playing 2k and down. Focus on moving image with time alignment and a little bit of level changing

If 2k and up. Its pretty level dependent.

Sent from my XT1710-02 using Tapatalk
This is pissing in the wind. If delays are set properly and your center image is still off, you should be using measurement and verify with ears to see if pairs of drivers are equal volume from side to side. More times than not, they may measure similar, but one side will be a bit louder when verified by ear. Use levels to adjust. Otherwise, you are just introducing comb filtering. If levels sound and measure right, you might want to revisit how you are setting delays, whether it means being more precise with the tape measure, or by using a tape measure from the get go instead of trying some random method you read on this site.

Just curious rayray, where does your center sound like it's coming from? In front of you? Center of the dash?

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This is pissing in the wind. If delays are set properly and your center image is still off, you should be using measurement and verify with ears to see if pairs of drivers are equal volume from side to side. More times than not, they may measure similar, but one side will be a bit louder when verified by ear. Use levels to adjust. Otherwise, you are just introducing comb filtering. If levels sound and measure right, you might want to revisit how you are setting delays, whether it means being more precise with the tape measure, or by using a tape measure from the get go instead of trying some random method you read on this site.

Just curious rayray, where does your center sound like it's coming from? In front of you? Center of the dash?

Sent from my SM-G975U using Tapatalk

I've tried several tuning methods and what I found that works best for me is:

1. Set T/A By Tape Measure.
2. Level Match all Left Side to Target Curve as Close as Possible.
3. EQ Left Side to match Target Curve.
4. Make the Left Side my new target curve and match the right to left.

Even then I find that I have to adjust the volume level of the left side slightly. Otherwise the vocals have an image directly in front of me, and not at the center of the dash.
 

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Skizer, I set ta by using a tape measure. Center image is a few inches to the left. This is a 3 way front stage. Midbass is crossed 80-200hz, midrange is 200-4khz, tweets 4-20khz. Sounds like a phase issue below 200hz, as I can add additional delay to the left midbass and image doesn’t move much to the right regardless. They are correct as far as polarity.
 
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