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I have decided to spend some money in a mic, and would appreciate any comment on this Audio Techica stereo mic: AT pro 24

http://www.audio-technica.com/cms/wired_mics/5f7e96b21f21e6b3/index.html

(in Spanish :http://www.audio-technica.com/cms/wired_mics/72c2f3ac87f777f2/index.html)

At 109 Euro + shipping it does not look very 'professional', I know, but on the other hand it is light and small (this is a MUST), needs no phantom power and with the 3.5 mm jack i DO need to plug it into the iRiver hard-disk juke box I'm using (shifting to a better device will have to wait). Intended use is recording natural sounds from birds to streetnoise... while carrying it in a overloaded backpack )

Please let me know what you think!

Cheers, and thanks in advance
Dob

dobroide
I have decided to spend some money in a mic, and would appreciate any comment on this Audio Techica stereo mic: AT pro 24

http://www.audio-technica.com/cms/wired_mics/5f7e96b21f21e6b3/index.html

(in Spanish :http://www.audio-technica.com/cms/wired_mics/72c2f3ac87f777f2/index.html)

At 109 Euro + shipping it does not look very 'professional', I know, but on the other hand it is light and small (this is a MUST), needs no phantom power and with the 3.5 mm jack i DO need to plug it into the iRiver hard-disk juke box I'm using (shifting to a better device will have to wait). Intended use is recording natural sounds from birds to streetnoise... while carrying it in a overloaded backpack )

Please let me know what you think!

Cheers, and thanks in advance
Dob

I've compared the specs to those of the AT 822, another stereo microphone, $419 USD, and the Neumann KM140, which is a common mono cardioid condenser.

You can find the specs for the Pro 24 here:

http://www.audio-technica.com/cms/wired_mics/5f7e96b21f21e6b3/index.html

The first thing I noticed about the Pro24 is that the cable is permanently attached to the microphone. This is not a good thing. It will fail eventually.

The frequency chart is mediocre: The microphone rolls off pretty steeply starting around 200Hz, but that might not be a bad thing if you are going to be hand holding it, since there is no rolloff switch. There is a rise around 4kHz to 10kHz, which might make it sound a bit brittle or shrill. But charts can't really give an accurate indication of how it sounds.

There are some other interesting numbers though:

OPEN CIRCUIT SENSITIVITY -50 dB (3.1 mV) re 1V at 1 Pa

MAXIMUM INPUT SOUND LEVEL 119 dB SPL, 1 kHz at 1% T.H.D.

DYNAMIC RANGE (typical) 82 dB, 1 kHz at Max SPL

SIGNAL-TO-NOISE RATIO 57 dB, 1 kHz at 1 Pa

Open circuit sensitivity is how loud the microphone is. The louder the microphone, the less you have to crank up your pre-amp. 3.1 mV is not particularly sensitive. For comparison, the AT 822 is 5.6 mV re 1V at 1 Pa, and the Neumann KM140 is 15 mV/Pa ,

Maximum input sound level is how loud of a sound it can record before it starts to distort. 119dB SPL, while loud, is not that uncommon out on the street. For comparison. For comparison, the AT 822 is 125 dB SPL, and the Neumann KM140 is 144 dB*. This is the number at which 1%THD can be measured. Higher end manufactures will use 0.5% THD. Using 1% THD inflates AT's specs by 6dB.

Dynamic range is the difference between the noise floor (the self noise of the microphone) and it's maximum SPL. 82dB is not as much dynamic range as a CD, If we were to quantify it in terms of bit depth, you could only make a 13 bit recording with this microphone. Dynamic range is usually not quoted in microphone specs, because it can be derived from the other specs. The reason that AT used this is because they are playing games with the next number, signal to noise. For comparison, the AT 822 is 101 dB SPL, and the Neumann KM140 is 128 dB*.

Usually manufacturers will give a microphones self noise, not the signal to noise ratio. This is how loud a microphone's circuitry is-- It's the hiss you hear when you turn up the pre-amp. The lower the number the better. Their number of 57dB S/N is meaningless by its self, but if you subtract the dynamic range from the Maximum Input Sound Level, you will get the self noise. 119dB-82dB= 37dB. For comparison, the AT 822 is 24dB and the Neumann KM100 is 22 dB*. The way they came up with 57dB is by saying that there is 20dB of headroom above the nominal level. 37dB + 20dB = 57dB.

So overall, I would say that this is not a stellar microphone, however, for $119USD, it's probably not a total waste of money.

For more information on reading mic specs ,check out:
http://www.dpamicrophones.com/page.php?PID=35

*AT measure distortion at 1%THD, Neumann measures it at 0.5%THD. If you were to compare apples to apples, AT's specs would be 6dB worse than published, or Neumann's 6dB better than published. I've taken the liberty of adjusting Neumann's data to match that of AT's, so if you look on Neumann's website, http://www.neumann.com/infopool/mics/produkte.php?ProdID=km100, there specs will be different than what I've quoted above.

I hope this helps you make an educated decission.

-Richard

RHumphries
...you will get the self noise. 119dB-82dB= 37dB. For comparison, the AT 822 is 24dB and the Neumann KM100 is 22 dB.

oops. I made a mistake. The Neumann's self noise is 16dB (A weighted).

-Richard

RHumpries, a great THANKS for the effort you took in writing a esponse and all the valuable info therein.

Before seeking opinions here I also looked at the specs for the AT822 (which I noticed you had used yourself sometimes). This mic seemed a bit pricey to me, but what I liked less was that it seemed oversized for a skinny backpacker. After reading you I'm probably even more hesitant than before, but that I have learnt a lot that's for sure !! Likely, choosing a piece of equipment represents a tradeoff of many factors...

Thank you again for your help. And by the way, I'm full of respect - and some envy - for your samples at Freesound

Cheers
Dob

Hi,

Perhaps the Rode NT-4 is your thing? It can be battery powered and comes with a xlr to mini-jack cable.
http://www.rodemicrophones.com/nt4_desc.asp?menu=nt4Menu
i dont own this microphone so i cant say anything about its quality but maybe Rhumpries can ?

Cheers
Anton
ps its a bit more expansive that your original choice but i think it should be about 300 dollars. (or look 2nd hand)

Anton
Hi,

Perhaps the Rode NT-4 is your thing? It can be battery powered and comes with a xlr to mini-jack cable.

wow, it looks superb! I had no idea such a beauty existed, thanks for the hint, Anton

Dob

I've decided to take at822.. the question is basically to RHumpies - as you've been using this mic quite often... Is it worth buying? basically i can afford something 100$ more expensive, so maybe Nt-4 would do the trick? The purpose is ambient sounds recording..

I use an AT835b while not stero I'm planning on upgrading to the NT4. Had a chance to use it a few times and love it.

Phorbox
I've decided to take at822.. the question is basically to RHumpies - as you've been using this mic quite often... Is it worth buying? basically i can afford something 100$ more expensive, so maybe Nt-4 would do the trick? The purpose is ambient sounds recording..

For the money, $250 USD, I like the AT, though it's probably not the best for very quiet ambiances. The NT-4, from the specs, definitely looks like a better mic. You will need some type of wind protection using either mic, so if your budget is really tight, I might go with the cheaper AT and spend the rest of the money on a suspension/wind shield.

Jut to muddy the waters some more... Another option would be a stereo pair of Oktava mics http://sound-room.com/customer/product.php?productid=18&cat=3&page=1 $375USD. or better yet (but probably too pricey), the stereo pair with 3 sets of capsules http://sound-room.com/customer/product.php?productid=17&cat=3&page=1 $660USD The up side is that you get two mics and you are not stuck with a single mic in an XY pattern. The down side is that you need to figure out some way to take them into the field, set them up in your favorite stereo configuration, and protect them from the wind. A stereo bar is not much trouble, but shielding it from the wind is. If they had a figure 8 capsule, it would be easy to stick a mid-side pair into a zeppelin, but an XY pair an ORTF or a spaced omni pair gets more complicated.

-Richard

Thanks for your replies)
Following Richard's advice, i'll consider buying AT822 and some wind protection.. I think that would be the best option just to start with. I also thought about oktava stereo pair (that might even be cheaper than 376$, as Oktava is located in Russia, just like me), but i don't want to mess with placing them yet.. So thanks again, i made my choice))

I found this dirt cheap option of 2 Soundelux CM-H8k stereo "matched" pair. with an x/y bar and shock mounts. for 89 euro's! (cardoid paterns i believe, but you can change the caps for omni or supercardoids, no figure 8 unfortunatly).

http://www.superlux.us/images/CM-H8K_series_datasheet.jpg

Any thoughts on it usabiltiy based on the given specs? (Richard perhaps?)

Im would use it in conjunction with Sound Devices 722. Basically to record ambience or concerts.
There is a bootleg recording done with these mikes online here: http://www.archive.org/audio/etree-details-db.php?id=28449&from=browseRecent

Ofcourse id love to consider more expensive options like Sennheiser or Rode mike;s but that will be a while since I spend a lot of money on the 722 (Dont worry I got my shotgun mike and 2 LD mikes to keep me busy in the mean time.)