# Measuring Mics - what do you use?



## Zeitgeist (Apr 4, 2009)

I have a Dayton EMM-6 that I had calibrated by Cross Spectrum Labs that I've been very happy with. I also have an Audyssey APM-1 that I keep debating getting calibrated.

Does anyone on HTS use any more exotic (higher priced) measuring mics that they use for measurements? IE, Earthworks/Audix/B&K/Josephson/etc.

Just curious. I just keep thinking about investing in a more expensive mic. Not a DPA 4007 ($2k) though.


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## SAC (Dec 3, 2009)

Yes.

As well as 'higher end' more capable pre-amps and analysis software.

But before you buy ANYTHING, please sit down and define exactly what you need to do and what are the critical compliancies that need to be satisfied. The accuracy and precision, as well as the necessary capabilities, depend upon the scope and purpose of what you are doing.

Simply having a bag of expensive 'name' gear, while it may impress those less intimate with what is actually being done (and whose opinion doesn't really matter!), but it alone will not accomplish anything. Especially if you later discover that you need to re-buy a piece of gear in order to acquire the actual capability/specs that you need.


If you need greater precision and accuracy, the next step might be any of the following, in order of increasing cost Audix TR-40A (now replaced by the the much more reliable and consistent TM-1),TEF04, TEF05, or Earthwork M30xx. Above that there are such brands as Testmic, Josephson and DPA (with the DPA 4007 for about $1700 being about as high as you would ever go).

As far as pre-amps featuring increased linearity in terms of both phase, frequency response and, perhaps most significantly, noise floor (S/N), units made by MAudio, PreSonus, Edirol and Duran.

But before you move up in terms of equipment quality, I would first suggest you look at 2 channel FFT capability such as is offered by platforms such as ARTA and 'up'. (ARTA, which is priced at 79 Euros, is a definite steal now with the drop in the Euro relative to the USD). And beyond that there is Easera, RoomCapture, and TEF, etc., as well as platforms oriented more toward live sound such as Smaart, SysTune and WaveCapture. But again, it all depends on matching your actual application needs with your equipment. 

And additional useful accessories might be a calibrator and even a wireless unit, but I will warn you that 'any' wireless unit will not suffice, and that as you do not want it to be a limiting factor that you will almost necessarily be looking at a high end unit such as an Lectrosonics (400A or equivalent)...

Don't just buy a name! Buy specific capabilities matched to you actual needs.


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## tonyvdb (Sep 5, 2007)

Ive used the Audio control SA3055 to EQ my mains, the microphone alone is $400 (yes we had to replace it once) That I borrow from my church. I also use my Galaxy CM140 for just general readings and with REW.


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## Zeitgeist (Apr 4, 2009)

SAC said:


> Yes.
> 
> As well as 'higher end' more capable pre-amps and analysis software.
> 
> The accuracy and precision, as well as the necessary capabilities, depend upon the scope and purpose of what you are doing.


What do you use? 

I'm familiar with some of the professional and lab software and solutions (ie dn6000, TEF, systune,Smaart). I have Smaart for example.


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## SAC (Dec 3, 2009)

It depends.

For basic 2 channel use I use the Duran D-Axys preamp (higher all around precision and significantly greater S/N), an Earthwork M30 and Easera. I also carry the Easera Gateway (both have integral hardware loopback configured internally). The Gateway allows TDS to run on the Easera platform allowing me to leave the TEF20 at home for the use of basic TDS applications where the additional noise immunity is required (...it sure is nice to be able to run sweeps on a large high noise SR system environment while AC/DC is simultaneously playing over the system under test and without entertaining the fantasy of expecting the SR system, union apes and/or setup crews to become silent! Try using any other platform in such a hostile (read "normal") environment where the ambient noise is treated just like part of the test signal as the tow motors' backup beepers are sounding....!!!:yikes: Again, it all depends on one's application the environment and the precision required...). 

For multi-channel input requirements I have 2 PreSonus Firestudio Projects allowing ~12 channels of input for use with either Systune or Easera Pro (that significantly decrease measurement time for such multi- channel testing applications as generating polar plots for speakers or for distributed live use with SysTune).

The basic workhorse is usually one or more of the matched Earthworks M30s, either phantom powered or occasionally the BX battery powered unit. 

I also have multiple TEF04s for utility use - especially when I am in an auditorium competing with the dreaded 'chair carts' (for those not familiar, it never ceases to hurt having a microphone destroyed or damaged, regardless the cost - and _especially_ awkward if you do not have a spare!!!); and for various applications, an array of mini omni Crown CM-10s, a handful of variously compliant accelerometers, a Crown SASS, a few Crown PZMs (as well as a variety of variously configured Plexi-glas mounting panels) and even a couple of Sennheiser 421s and Shure SMs, as well as several stereo mics (AT4050), etc.... but that quickly enters the wider realm of testing for a wide range of applications, far beyond what most are concerned with here... For NLA (noise level analysis) needs where the system has to be calibrated and certified, the Earthworks are sufficient there are well. Also there are 2 dodecs (dodecahedron) and subs for driving various rooms available as well.

Needless to say, for a complete kit, you are looking at several bags, an ATA roadcase, and assorted cases for additional heavy and awkward devices that you really would like to avoid carrying if at all possible - especially if traveling. Thus defining exactly what you want to do, and establishing a measurement plan is the first step. Advances in non-destructive post processing are a God send in this respect, but it fails to provide for that measurement you were either unable to take or for which one's planning simply failed to anticipate.

_But for basic small room measurements the Duran D-Axys pre-amp, the Earthworks M30, and Easera are the de facto go to platform. _That is perhaps the simplest answer that would address the question asked above as well as for what most are wanting to do on this site. Note, especially if flying*, it may be necessary to arrange for additional materials to be securely shipped or otherwise provided on site.

Things become more complicated than I would like as no one platform does everything one would like, and it quickly becomes a case of Fibber McGee's closest as to what combination/permutation of gear is necessary to do everything that one may need to do depending upon the nature of the space and/or the application - a fact that renders traveling with this stuff a royal pain if one must attempt to limit the selection and/or clear security at an airport as well as carry on the gear (while still allowing for a toilet kit and a change of clothes) that one does not relish being 'lost', damaged or destroyed by baggage handlers.

As far as associated useful accessories, a 'regular' boom mic stand and a tall 12 foot lighting stand for positioning the mic in the wall-ceiling corner. And if there is no flying involved (as flying with the larger - "it must be a bomb" - carry-on rack is a PAIN with TSA!) - a coaxial speaker source, Dodecs and sub, plus a rack mounted Crown D75A (along with a PreSonus FireProject Studio, and TEF20 that affords multi-channel &/or PolarETC capability respectively), are generally lugged about if no suitable in-place sound system is available. But in traveling with the gear, planning is _necessary_ as the goal is always to anticipate the necessary measurements as well as to then bring only as much as is absolutely needed (while providing for the care or replacement of _critical_ tools such as a spare mic) depending upon the task and venue and to arrange for either the secure shipment or an arrangement for such material to be provided on site; while one is afforded a bit more latitude if one drives.

*Trust me, while it sounds glamorous, flying with this stuff has always been a royal pain (compounded dramatically by trying to carry ANY rackmount gear), made all the worse by the geniuses with TSA. Its truly difficult to capture the atmosphere when a committee of TSA agents who barely figured out how to walk through the door entering the building stand in a circle trying to determine just what kind of a bomb a 3-4U rackmount case full of electronics gear constitutes, let alone an additional Pelican case filled with a computer and still more electronics, a toilet kit, a pair of underwear, a spare shirt and maybe a Subway sandwich....


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## Wayne A. Pflughaupt (Apr 13, 2006)

Zeitgeist said:


> I have a Dayton EMM-6 that I had calibrated by Cross Spectrum Labs that I've been very happy with. I also have an Audyssey APM-1 that I keep debating getting calibrated.
> 
> I just keep thinking about investing in a more expensive mic.


As long as you’re only doing home measurements for the main speakers and/or subs, there’s no reason to use a more expensive mic. As you know, the calibration file takes care of any deviations from flat response. All you’d be getting with a better mic that presumably has flatter native response is a calibration file with fewer and less severe corrections. That won’t matter a bit when you go to measure, and assuming the two are virtually identical physically – i.e. same type and size element, same case construction, etc. – you won’t see a difference in the measurements. Frequency response measurements, at least – can’t speak for other types.

That said, there might be a good reason for some people in some situations to go with a different mic. For instance, it might be beneficial to have a mic that exhibits flatter high frequency response off-axis. Or one that exhibits good response at the frequency extremes (i.e. beyond 20 Hz or 20 kHz). But unless you have a specific need for the particular characteristics of such a mic, there’s no reason to go that route.

Regards,
Wayne


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## Zeitgeist (Apr 4, 2009)

Thanks SAC - Appreciate the lengthy response. I'm not familiar with Easera - sounds pretty interesting. I'd never thought too much about doing analysis in a noisy (hostile). Never occurred to me that you COULD get good results with a poor SNR.

I thought your comments about TSA were interesting / tragic. I'm all too familiar with the challenges (putting it politely) that they can present. The last time I had a bag checked they were more upset about a bag of gummy candy than a backpack full of radios and electronics. I can't even imagine traveling with rack-mount gear.

--

Thanks as well Wayne. I had a feeling that the better mics had a flatter response (needing less correction) - but was curious what the other benefits really are. I read that the diaphragm design on some gives better temperature stability - which I thought was interesting. Appreciate the sanity check.


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