ECM8000 - THD and IMD performance

percy · 22nd July 2010, 02:49 PM

Hi,
does anyone know where can I find specs or measurements of THD and IMD performance of the mic itself ?
I have searched and found bits and pieces of information here and there but no full range specs or measurements. I am interested in finding the THD and IMD performance of this mic across the band i.e. 20hz-10Khz.

Pano · 22nd July 2010, 03:16 PM

This is a good question and I'd love to see the specs. Don't think I've ever seen mic distortion specs. An actual plot would be even better.

I use the ECM-8000 to measure distortion of speakers, but can really only use it as a relative measurement as I have no idea what the distortion of the mic is.

Helmuth · 22nd July 2010, 04:40 PM

Ask the engineers of behringer.

percy · 22nd July 2010, 07:03 PM

did already. basically they said at that price point they don't go into all that detail so these specs are not even available for this product.

I know Zaph uses this mic for his distortion measurements. Wonder if he has any info to share ?

markus76 · 22nd July 2010, 07:31 PM

Contact Herb with Cross·Spectrum Labs - Sound | Vibration | Engineering
Nice guy that can also provide calibration for your mic.

catapult · 12:58 AM

Cross-Spectrum Microphone Calibration Service - USA - Page 4 - Home Theater Forum and Systems - HomeTheaterShack.com

Cross-Spectrum Microphone Calibration Service - USA - Page 4 - Home Theater Forum and Systems - HomeTheaterShack.com

Herb's ACO mic is probably pretty low distortion at the levels being measured so its distortion is probably mostly due to the speaker. The Behringer mic's distortion would be the difference between the two mics.

twest820 · 23rd July 2010, 12:58 AM

I've wondered about this as well but likewise didn't find much in the way of data. Can't comment on the ECM8000 but with the Dayton EMM6 I have (cal'ed from Herb, pretty similar to the old ECM8000s) I've measured THD as low as -55dB, which is basically a measurement of the noise floor. So it seems good enough.

In my experience THD's usually a reasonable proxy for IMD so I'd expect IMD levels to be comparable.

Pano · 23rd July 2010, 02:19 AM

OK, cool. So you've seen THD at 55dB below the test tone? Do you remember what the SPL was?

In the pages linked, they are running at levels far above where I test, so it may not be a worry in the mid 90dB SPLs.

percy · 23rd July 2010, 03:05 AM

Quote:

Originally Posted by catapult

Cross-Spectrum Microphone Calibration Service - USA - Page 4 - Home Theater Forum and Systems - HomeTheaterShack.com

Cross-Spectrum Microphone Calibration Service - USA - Page 4 - Home Theater Forum and Systems - HomeTheaterShack.com

Herb's ACO mic is probably pretty low distortion at the levels being measured so its distortion is probably mostly due to the speaker. The Behringer mic's distortion would be the difference between the two mics.

I wish the same thing would have been mentioned for a few more frequencies as well in addition to 30hz and 1Khz.

Also, I too am interested in knowing about distortion figures only in the sub-120db level - more like in the 90-95db range. I really dont care about how much spl the mic can handle before reaching a said amount of distortion.

catapult · 03:41 AM

None of these Panasonic-based mics are going to distort enough at 90dB to worry about. As twest said, it will be down in the noise floor. The noise is fairly high with my Dayton, ~39 dBA as measured by Herb.

Edit: that's the total A-weighted noise summed across the audio band. The noise will be lower at any particular frequency.

22nd July 2010, 02:49 PM	#1
percy diyAudio Member Join Date: Apr 2004 Location: MN	ECM8000 - THD and IMD performance Hi, does anyone know where can I find specs or measurements of THD and IMD performance of the mic itself ? I have searched and found bits and pieces of information here and there but no full range specs or measurements. I am interested in finding the THD and IMD performance of this mic across the band i.e. 20hz-10Khz.

22nd July 2010, 03:16 PM	#2
Pano diyAudio Moderator Join Date: Oct 2004 Location: North Carolina Blog Entries: 4	This is a good question and I'd love to see the specs. Don't think I've ever seen mic distortion specs. An actual plot would be even better. I use the ECM-8000 to measure distortion of speakers, but can really only use it as a relative measurement as I have no idea what the distortion of the mic is. __________________ Take the Speaker Voltage Test!

23rd July 2010, 12:54 AM	#6
catapult diyAudio Member Join Date: Dec 2002 Location: Planet Earth	Cross-Spectrum Microphone Calibration Service - USA - Page 4 - Home Theater Forum and Systems - HomeTheaterShack.com Cross-Spectrum Microphone Calibration Service - USA - Page 4 - Home Theater Forum and Systems - HomeTheaterShack.com Herb's ACO mic is probably pretty low distortion at the levels being measured so its distortion is probably mostly due to the speaker. The Behringer mic's distortion would be the difference between the two mics. __________________ Dennis H Last edited by catapult; 23rd July 2010 at 12:58 AM.

23rd July 2010, 02:19 AM	#8
Pano diyAudio Moderator Join Date: Oct 2004 Location: North Carolina Blog Entries: 4	OK, cool. So you've seen THD at 55dB below the test tone? Do you remember what the SPL was? In the pages linked, they are running at levels far above where I test, so it may not be a worry in the mid 90dB SPLs. __________________ Take the Speaker Voltage Test!

23rd July 2010, 03:33 AM	#10
catapult diyAudio Member Join Date: Dec 2002 Location: Planet Earth	None of these Panasonic-based mics are going to distort enough at 90dB to worry about. As twest said, it will be down in the noise floor. The noise is fairly high with my Dayton, ~39 dBA as measured by Herb. Edit: that's the total A-weighted noise summed across the audio band. The noise will be lower at any particular frequency. __________________ Dennis H Last edited by catapult; 23rd July 2010 at 03:41 AM.


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22nd July 2010, 04:40 PM	#3
Helmuth diyAudio Member Join Date: Oct 2008 Location: Winterswijk	Ask the engineers of behringer.

22nd July 2010, 07:03 PM	#4
percy diyAudio Member Join Date: Apr 2004 Location: MN	did already. basically they said at that price point they don't go into all that detail so these specs are not even available for this product. I know Zaph uses this mic for his distortion measurements. Wonder if he has any info to share ?

22nd July 2010, 07:31 PM	#5
markus76 diyAudio Member Join Date: May 2008 Location: Switzerland	Contact Herb with Cross·Spectrum Labs - Sound \| Vibration \| Engineering Nice guy that can also provide calibration for your mic.

23rd July 2010, 12:58 AM	#7
twest820 diyAudio Member Join Date: Jun 2009 Location: Orygun	I've wondered about this as well but likewise didn't find much in the way of data. Can't comment on the ECM8000 but with the Dayton EMM6 I have (cal'ed from Herb, pretty similar to the old ECM8000s) I've measured THD as low as -55dB, which is basically a measurement of the noise floor. So it seems good enough. In my experience THD's usually a reasonable proxy for IMD so I'd expect IMD levels to be comparable.

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