In need of Dirac measurement screenshots (analysis complete)

[barrak]

Jan 18, 2015 21:36:41 GMT -5 tubby said:

Jan 18, 2015 19:25:27 GMT -5 barrak said:

Actually, the curve Dirac chose for us is not bad at all. It is fairly straight from 20 Hz to 20 KHz with an overall ~5 dB drop. A few years ago Harman International conducted and published a study about a controlled experiment involving target curve preferences. They concluded that a straight target curve (similar to Dirac's) was best pleasing for the chosen critical listeners, albeit with an overall drop of 10 dB.

Until Full Dirac is available, I would suggest that XMC-1 users raise the sub level (after programming the filters) by 3-6 dB. That should bring the bass back in full force. I wouldn't go any higher though.

I agree with your sentiment in regards to the Dirac target curve but don't confuse target curve with microphone calibration. The calibration file for the mic is to ensure the measurement is correct. if the measurement is not correct it does not matter what the target is because the correction will not be correct.

I would also say that it would not be appropriate to use a calibration file that is not specifically created for you mic. There can be large enough variation between mics that they require a specific calibration for each mic. This is why mini dsp has a serial number specific file available for it's mics and why Cross Spectrum calibration is so popular. As far as I can tell the calibration provided for the EMM is the same file for everyone, unless they have somehow tied the specific mic to the Dirac user key, not likely. But this means that to some degree or another not all the mics will provide the correct response to Dirac.

Here is an example between my Umik and the 90 Degree cal file from Mini DSP vs the EMM and the cal file provided in the Dirac download. This is Front left 80z crossover to subs. Tis tells me one of the cal files is not correct and I tend to believe the Mini DSP file more than the Emo one.

Your results are very unsettling. If the mic is coming with a generic calibratrion file then it is next to useless. I just looked up the calibration files for my old Tact mics (which came with serial numbers and distinct calibrarion data that list the mic serial number in the table heading). The variation (from max to min) is 3.4 dB on one and 0.8 dB on the other. The mics look identical except for the serial number stickers.

[socketman]

Tubby, I have a brand new EMM enroute to Herb at CS which should arrive on Wednesday and then he will calibrate it fully and then we will have a definitive answer.

[ansat]

I don't believe that an generic calibration file is useless. But the reason that I asked for the graphs is that I am looking to see how Dirac is acting on the high frequencies across many different speakers in many different rooms. All of us that have cross-spectrum calibrated microphones are having trouble getting the cross-spectrum microphones and the EMM-1 in agreement. We are also seeing that the disagreement has some variation from each other, its always in the same direction. I have reached out to emotiva and to Dirac, and their measurements are showing that the calibration files are ok. In these graphs I identified one microphone that is really bad, and the rest tend to exhibit the same pattern. Almost all of our speakers needed Dirac to add gain to the high end and a lot of times, it seems to be about the same amount. Given that we are on an house curve, I find it odd that we exhibit this trend. The second trend is how much bass we all seem to have. Rooms add bass, I get that, but it seems like more then I would of thought.

But since emotiva cannot reproduce what some of us are seeing, I am at a loss of where to go from here. We are not long off from the Dirac upgrade and that is the tool to use for tailoring a curve to taste. But I have concerns with feeding it a general calibration file that I cannot get to measure the same as my cross-spectrum files. Using the cal file that I created, The microphones are now in agreement.

I cant wait to see the cal results.

Tony

[markc]

Jan 18, 2015 23:00:38 GMT -5 ansat said:

I don't believe that an generic calibration file is useless. But the reason that I asked for the graphs is that I am looking to see how Dirac is acting on the high frequencies across many different speakers in many different rooms. All of us that have cross-spectrum calibrated microphones are having trouble getting the cross-spectrum microphones and the EMM-1 in agreement. We are also seeing that the disagreement has some variation from each other, its always in the same direction. I have reached out to emotiva and to Dirac, and their measurements are showing that the calibration files are ok. In these graphs I identified one microphone that is really bad, and the rest tend to exhibit the same pattern. Almost all of our speakers needed Dirac to add gain to the high end and a lot of times, it seems to be about the same amount. Given that we are on an house curve, I find it odd that we exhibit this trend. The second trend is how much bass we all seem to have. Rooms add bass, I get that, but it seems like more then I would of thought.

But since emotiva cannot reproduce what some of us are seeing, I am at a loss of where to go from here. We are not long off from the Dirac upgrade and that is the tool to use for tailoring a curve to taste. But I have concerns with feeding it a general calibration file that I cannot get to measure the same as my cross-spectrum files. Using the cal file that I created, The microphones are now in agreement.

I cant wait to see the cal results.

Tony

Tony, I think we could speak a little louder on this. I don't have an XMC but have been tentatively following these forums as a potential buyer.

It seems incredulous that every single poster, without exception, on these forums has speakers (and many have high end audiophile speakers) that have tweeters which downplay the high frequencies (or rooms which mask them) and so Dirac has to boost the highs to compensate for the low volume of the higher frequencies. Many people have tweeters that have a response up to 30kHz or even 100kHz for ribbon tweeters.

Similarly, it seems incredulous that every single poster on these forums have speakers/rooms which provide too much bass when they are in their unadjusted state so that Dirac feels it needs to apply filter cuts to the low end to compensate and decre4ase the bass, even given the slight rise of the target house curve at the low end.

Surely this points to either a microphone sensitivity / calibration file problem or an XMC-1 tone generator problem or both.

I can't see if anyone has measured their fronts in REW using an alternative calibrated mic and then done the same using the EMM-1 with it's supplied file to see if the speakers unadjusted in room response curve is the same.

I don't think the problem is with the house curve chosen, or the calculated filters to get the response closer to the target curve, but the accuracy of the measurements.

Mark

[Priapulus]

We must be given the ability to input our own microphone calibration file; every other acoustic software allows us to do so. It allows us to get our EMO mikes independently calibrated, or use our own calibrated mikes. It is unreasonable to expect the EMO mikes to all hit the same calibration curve, no other microphone maker can do that.

Why not? There can be no proprietary risk to Dirac; it would simply allow their software to work better. It could be made a feature of the paid version of Dirac.

Sincerely
/b

p.s. I see the same thing, my treble is too bright, but no bass.

[klinemj]

Lack of calibration files specific to each mic has concerned me. Tony...will you be aggregating your data in a way you can easily show, or should we root through the data one by one like you did?

Mark

[ansat]

Ok, based on data that we gathered here, dirac is looking deeper into what we are seeing.

Dirac would like to know if anyone that posted their chart took their measurements with the microphone pointed anywhere but up.

Please respond promptly.

Tony

Edit: added noun.

[weigle2]

Jan 19, 2015 8:18:31 GMT -5 ansat said:

Ok, based on data that we gathered here, dirac is looking deeper into what we are seeing.

Dirac would like to know if anyone that posted their chart took their measurements with the microphone pointed anywhere but up.

Please respond promptly.

Tony

Edit: added noun.

All measurements taken with Mic pointing up.

[ansat]

Mark, for the most part, it shouldn't need to be spot on. But at the same time, Dirac should no show trends. Based on the graphs, it's really easy to say that using dirac will increase your treble and decrease you bass. (Which is what it has done for the charts posted.) And that is just not the case. That trend didn't exist when we used the trial.

If you look at some of the charts posted elsewhere, we should see a wide variety of different graphs with no patterns other then that we all have a little bit of bass that is out of control. (Room modes and reflections)

Tony

Jan 19, 2015 8:18:14 GMT -5 klinemj said:

Lack of calibration files specific to each mic has concerned me. Tony...will you be aggregating your data in a way you can easily show, or should we root through the data one by one like you did?

Mark

[rogersch]

Jan 19, 2015 8:18:31 GMT -5 ansat said:

Ok, based on data that we gathered here, dirac is looking deeper into what we are seeing.

Dirac would like to know if anyone that posted their chart took their measurements with the microphone pointed anywhere but up.

Please respond promptly.

Tony

Edit: added noun.

All measurements with MIC pointed up!

[tubby]

Jan 18, 2015 22:29:14 GMT -5 socketman said:

Tubby, I have a brand new EMM enroute to Herb at CS which should arrive on Wednesday and then he will calibrate it fully and then we will have a definitive answer.

Looking forward to your results.

[tubby]

Jan 19, 2015 8:18:31 GMT -5 ansat said:

Ok, based on data that we gathered here, dirac is looking deeper into what we are seeing.

Dirac would like to know if anyone that posted their chart took their measurements with the microphone pointed anywhere but up.

Please respond promptly.

Tony

Edit: added noun.

Up.

[tubby]

Jan 19, 2015 7:55:50 GMT -5 Priapulus said:

We must be given the ability to input our own microphone calibration file; every other acoustic software allows us to do so. It allows us to get our EMO mikes independently calibrated, or use our own calibrated mikes. It is unreasonable to expect the EMO mikes to all hit the same calibration curve, no other microphone maker can do that.

Why not? There can be no proprietary risk to Dirac; it would simply allow their software to work better. It could be made a feature of the paid version of Dirac.

Sincerely
/b

p.s. I see the same thing, my treble is too bright, but no bass.

It is possible to use your own file. It is just not a straight forward as other Dirac releases/measurement programs and directions are not supplied.

I don't want to widely give out the step by step at this point until Dirac and Emo have had a chance to respond to Tony.

[tubby]

Jan 19, 2015 2:13:34 GMT -5 markc said:

...I can't see if anyone has measured their fronts in REW using an alternative calibrated mic and then done the same using the EMM-1 with it's supplied file to see if the speakers unadjusted in room response curve is the same...

See my post on page 2, 4th from the bottom. My Umik vs the Emm

[geebo]

Jan 19, 2015 8:18:31 GMT -5 ansat said:

Ok, based on data that we gathered here, dirac is looking deeper into what we are seeing.

Dirac would like to know if anyone that posted their chart took their measurements with the microphone pointed anywhere but up.

Please respond promptly.

Tony

Edit: added noun.

Mic pointed straight up to the ceiling for me.

[thompson12]

straight up

[rocky500]

straight up too

[barrak]

While I still believe that a custom calibrated mic is critical for such high-tech implementation, a large part of the issue could be mitigated by proper target curve selection/control. Here is a typical (and editable) Tact TCS target curve. There are others with various degrees of bass hump and/or treble roloff.



See... even my audiophile lizard agrees with me (just popped out from under the keyboard while typing this reply).



Tony, my mic was pointed up. However, AGC was on. I'll remeasure tomorrow with it off, while the kids are in school and repost.

[ansat]

Jan 19, 2015 10:25:03 GMT -5 barrak said:

While I still believe that a custom calibrated mic is critical for such high-tech implementation, a large part of the issue could be mitigated by proper target curve selection/control. Here is a typical (and editable) Tact TCS target curve. There are others with various degrees of bass hump and/or treble roloff.

View Attachment

See... even my audiophile lizard agrees with me (just popped out from under the keyboard while typing this reply).

View Attachment

Tony, my mic was pointed up. However, AGC was on. I'll remeasure tomorrow with it off, while the kids are in school and repost.

I agree, for some of us, we want absolute control. But the LE version was supposed to satisfy the needs of most users out there. I think that the way this was implemented has the lowest learning curve and it what is needed for such a wide user base. For the full version, I do hope that a custom cal can be loaded via the software and other calibration microphones can be used.

Tony

[rogersch]

Jan 19, 2015 11:22:42 GMT -5 ansat said:

I agree, for some of us, we want absolute control. But the LE version was supposed to satisfy the needs of most users out there. I think that the way this was implemented has the lowest learning curve and it what is needed for such a wide user base. For the full version, I do hope that a custom cal can be loaded via the software and other calibration microphones can be used.

Tony

I agree but if the result of a DIRAC LE version is worse than no room correction than it is useless.... Well I've switched DIRAC completely off.
Hopefully in the full version you can use other mic's or at least use a specific calibration file for the EMM without tricks.