Dayton EMM-6 vs Cross Spectrum EMM-6

[johnnyrichards]

Caption contains pertinent information.

My S/n 0239 I bought Spring of 2010. The CSL arrived in the mail Monday. The 0239 uses factory provided cal file, and I downloaded the 5204 cal file from Dayton Audio and compared it to the Cross Spectrum cal file for that mic. The older mic is reasonably close to the CSL results, but the newer mic is off far enough to yield some significant tweeter padding issues.

This is all I have on it, just thought I would share.

[chrisn]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Interesting, I wondered how close they would be. Thanks for sharing. Tweeter padding takes some listening to get it right, but thats part of the fun

[Chris Roemer]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Hey Johnny.

I've got a Dayton EMM-6 that was cal'd by CSL about 2 years ago. The 2 cal files are night and day apart. The CSL curve looks like your "typical" panni condenser capsule: fairly flat up to 2-4k range (from memory) then going +4dB (or so) up by 10-12-14k where it basically flattens out.

My downloaded ("custom") cal file from Dayton for my sn looks c-r-a-z-y. It's all over the place.
I downloaded almost a dozen cal files from Dayton and many of them have an odd pattern that's common across mics. Kinda looks like a measuring artifact.

[andy19191]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

My downloaded ("custom") cal file from Dayton for my sn looks c-r-a-z-y. It's all over the place.

Mine is also nonsense. If the microphone had a response the opposite of the "calibration curve" it would be broken. Thankfully the microphone produces a smoothish curve with a reasonable tweeter and is almost certainly OK. I just can't used for measurement until I get it calibrated.

[Pallas]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Here's another comparison, that also shows the difference between CSL's on-axis (for speaker measurements) and grazing (for listening position measurements) calibrations.

[ryanbouma]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Thanks for this Johnny. I've been struggling with my setup recently when I posted a tweeter measurement using my CSL calibrated ECM 8000. Three reputable DIY'er posted a measurement of the same tweeter and mine showed the treble being much lower. They aren't using CSL mics afaik, they're using Dayton cal mics. So I did this:

Compared a few tweeter measurements of mine to zaphs. Check.
Ordered a UMIK from CSL to eliminate the sound card and compared. Check.
Remeasured in various manners. Check.

Everything I did I found I was ok. I'm suspecting I'm not at fault, rather the other measurers have mics that measure hot. But it's 3:1. Does CSL measure to low, or has Dayton started getting to hot? When I listen to a flat-according-to-my-mic system the treble sound quite spot on.

[carlspeak]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Can CSL calibrate Omni-mics?

[r-carpenter]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Can CSL calibrate Omni-mics?

Probably. If anything, Omnimic data can be compared to existing calibrated mic given the same conditions at which measurement has taken place. I may do it in a near future.

Ryan, I've actually compared 2 different mics calibrated by CSL and the results were near identical.

[carlspeak]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Herb Singleton lives not too far from me in Springfield, MA. He was a guest speaker at a CAS meeting a few years back. He discussed mics and calibrations. I'll probably have him do my new Omni-mic ver. 2 mic calibration. My first few measurements indicate it's reading pretty hot above 10K. I'm just wondering if my result is real or not, but will compare readings with my Behringer ECM8000 next chance I get.

[critofur]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

OK, so what I want to know is: what is Parts Express going to do to make this right?

I sure hope they fix their calibration system and ask everyone to send their EMM-6 mics back in to be properly calibrated. It shouldn't matter whether you've bought it 5 weeks ago or 5 years ago because the longer you've had it, the more you have to go back and re-do. :(

[Alien_Shore]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

A couple of thoughts here:
(1) mics do not stay calibrated forever. If you want to depend on your measurements over time, you'll likely want to invest in periodic re-calibration.
(2) when I spoke with [email protected] several months ago, I got the feeling that they will pretty much calibrate any mic that their equipment will support. I don't have my cal certificate with me right now, but I believe that they are using an ACO Pacific 7052 for their calibration services.

[johnnyrichards]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

A couple of thoughts here:
(1) mics do not stay calibrated forever. If you want to depend on your measurements over time, you'll likely want to invest in periodic re-calibration.
(2) when I spoke with [email protected] several months ago, I got the feeling that they will pretty much calibrate any mic that their equipment will support. I don't have my cal certificate with me right now, but I believe that they are using an ACO Pacific 7052 for their calibration services.

The CSL mic I bought was brand new. I am doubtful the calibration would have drifted that far between the Dayton calibration routine and Herb's routine. The other mic with the Dayton cal file still measures the same way as when I bought it in May 2010 - and it took a beating over the last three years. While I agree mics drift over time, implying this is the source of the problem is, IMHO incorrect.

[critofur]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Regardless of how much a mic might drift away from where it was at the time of calibration, if you are purchasing a calibrated mic one must place some trust in the entity doing the calibration that the calibration was at least accurate at the time of delivery. If that was not the case, then it should be made right (by, at the very least, offering a one time actual proper calibration).

Also, to me it seems bizare how rough Johnny's mics are - If I measure an XT25 tweeter with either my Berhinger 8000 or EMM-6 mic (or any of my homeade panasonic capsule mics) the FR looks much smoother,
and most of the measurements I've seen for those panasonic capsules are also much smoother than any of the graph lines on his chart?

For example, look at this one:



(From this thread: http://techtalk.parts-express.com/sh...ibration-files )

but, all my mics seem to have a fairly large dip before 20Khz.

[johnnyrichards]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Chris,

I do a short gate and 1/24th octave resolution. When I do a longer gate and lower resolution, my measurements more closely approximate the smoothed graphs most people post. I like to capture some of my rooms influence.

[critofur]

Re: Dayton EMM-6 vs Cross Spectrum EMM-6

Chris,

I do a short gate and 1/24th octave resolution. When I do a longer gate and lower resolution, my measurements more closely approximate the smoothed graphs most people post. I like to capture some of my rooms influence.

When I was saying how rough your graph looks I was talking about your mic's response* [in the OP], not speaker measurements - except in regards to where I mentioned the XT25 - however, when you measure nearfield the room becomes basically irrlelevant, which, is what you want when what your are trying to see is how smooth is you mic's response by using a tweeter known to be exceptionally flat in response as a reference. [When I measure an XT25 NF the sharp jaggy little spikes I observe tend to be ~ .1 db or so - even the "raw" measurement is nearly a flat line]

Take a look at my old RS28F vs RS28A measurement (1/24th octave also):



As to the gate, I generally use the "dual gate" or "multi gate" options to get the broadest view without sacrificing detail. I must admit though, when I look at the port output along with the near-field bass output of the woofer, I generally just "guesstimate" the summed output since far-field measurements in my room are so far from anechoic.

* - or was I wrong to assume that you are posting you'r mic's response in that chart, is that a speaker measurement? You do not state in the post that what you are posting as a speaker measurement so I had to assume it's your mic's response that you are posting there? Though I must admit it seemed quite odd that your mics had a ~10 db rise from 40 hz to 200 hz?!?