Topic: What portable recorder for very loud noise

[epicimages]

Hi guys, Im new here and i need some help.

Im not into audio, im a photographer, however i have been asked by some friends whos cars i regularly photograph, to make some videos.
I have the video all sorted with a few contour HD cameras and suction cups but its the audio i know nothing about. I have done as much research as i can, but sometimes it gets too technical for me to understand some articles.
I am looking at buying a portable audio recorder due to the ease of use, and its something i could locate around a car quite easily.

my problem is, i will be working with Ferraris, Lamborghinis etc... where i will be placing the recorder in the engine bay (suction cupped to the inside of the glass boot lid)

i have a feeling its going to get pretty damn loud in there. i have done some research and found the olympus LS-100 has a SPL of 140db.

is this the only unit that will record that loud?

i dont know the  dB i am working with, but for the sake of a recommendation, lets just say its pretty high.

what are the problems i would have if the recorder i buy will only record up to 100db and the sound is at 120db... will it just not produce the sound or will it get distorted?

i dont really have a budget, however i dont want to spend a lot of money on something i am probably only going to use a handful of times...
if i was to buy something in the 400-600 range, would i get my money back selling it second hand?

Thanks,

Dave

[keebs]

Hi Dave and all,

Unfortunately I don't have any many answers to this topic, but am looking for similar information so wanted to see if you'd figured anything out as well as bump this to the top.

It's quite surprising to me that none of the portable recorders provide proper specifications like THD @ certain input voltages for line-in's and SPL levels for included microphones.  Not only that, but they also don't include frequency response plots for the included mic's... strange. 

"what are the problems i would have if the recorder i buy will only record up to 100db and the sound is at 120db... will it just not produce the sound or will it get distorted?"

The one thing I can contribute is that yes, the recorded signal will distort.  Distortion creates harmonics of the level that's exceeding the input limit.  This is perceived to be worse the lower in frequency the offending signal is because a 50 Hz overload will produce harmonics at 100, 150, 200, 250, etc.  I imagine Ferrari and Lamborghini engines will be roaring fairly low.

Hopefully somebody chimes in, otherwise we may be forced to go with the expensive olympus option,

T

[sk-1]

Here's my quick recommendation:

Forget about using internal mics on a handheld recorder for this application.

Buy the following: 2 x Shure SM11 miniature dynamic lapel mics (~$100/ea, you'll need to get them online, most shops don't have same day stock of them), and 1 x Tascam DR100 mkII (~$300), total = $500. Sell it all the next day for $400. Cheaper than renting the gear for the day.

The SM11's will distort at 160dB SPL (so are basically unclippable), are omni-directional which means they are more resistant to vibration/wind noise (A Good Thing in car recording), are tiny which is good for accurate placement, and have a long, thin, flexible cable which is good for sneaking through car door/engine bay seals. Wrap the capsule in a 4"x4" piece of fake fur for wind protection. Secure the mic/cables with lots of camera tape (not gaffer tape because it can take off paint)

The Tascam with its inputs set to MIC mode, and on minimum gain, can handle the output of the SM11 mics at up to 154dB SPL. It's a good match.

Recordings made with the SM11 will need to have bass boosted in post (low shelf eq, +12dB @ 200Hz) to counteract its low-end roll-off due to it being mainly designed for speech.

Car recording is kind of a hobby of mine, so if you don't mind some suggestions I'd recommend (with a 2 mic setup) putting one mic on the exhaust (out of the way of the pressure blasts and wind turbulence) and the other one in the engine bay but favouring the air intake, which is where a lot of the action is (but not too close because a Lamborghini V12 gulping in air will swallow it whole - then die). This may not be possible if the intake ducting runs out of the engine bay. In this case do some tests of whatever sounds most interesting. Either way it will be pretty freaking awesome, so enjoy it!

Good luck

Ben

[keebs]

Great recommendations Ben!  Sounds like this will be very helpful to Dave and probably for me as well.

Cheers,

Todd

[epicimages]

Thanks for the tips. Since the first post I have spoken with a friend who recommended a similar setup but mentioned this mic. http://www.bhphotovideo.com/c/product/839897-REG/Rode_STEREO_VIDEOMIC_PRO_Stereo_VideoMic_Pro.html

Mainly because I will probably end up using it with my dslr for video too.


I'm in no rush to purchase and $500 is no problem. What sites are good to deal with other than b&h?

[earmonger]

Looks like the price is pretty widely fixed on that Rode mic. Google product search  brings up  B&H, Adorama, Zzounds...the main variable would be the sales-tax situation in your state.

Personally I'm a big B&H fan--they are always at rock bottom or near it, and they stock everything.

The advantage to Ben's setup is that you can widely separate the two mics and mix the sound from two different areas around the engine. Whereas the Rode will give you the stereo image from one spot. Meanwhile, unlike the lapel mics, the Rode should give you the full bass roar without tweaking.

[epicimages]

Ultimately I will need lapel mic's for presenter/interview stuff so both might be the go.

[sk-1]

Hi epic, a drawback of the sm11 is that is not very sensitive and needs a lot of clean gain (beyond what most handheld recorders are capable of) to give a useable signal. This is what makes it great for recording loud things (won't clip your inputs), but for dialog/VO you will struggle to get healthy levels that aren't drowned in hiss. I believe rode make a condenser lapel which is probably quite reasonably priced and will treat you better than the sm11 for voice work.

[TimeBandit]

Thin k the Lambo / Ferrari engines will scream loud enough for get reasonable level on that mics 

[rocksuitcase]

for another audio perspective of car sounds, think about this: I used to work with a guy who was the acoustician at GM in charge of noise quieting, cancellation and how it related to car audio and the driver/listener experience. They used binaural heads to make various measurement of interior vehicle spaces: http://www.bksv.com/products/pulseanalyzerplatform/pulsesolutionsoverview/acousticapplications/soundquality/soundqualityforconsumerproducts.aspx.

Perhaps, you could use a consumer version of binaural, from the outside of the vehicle to capture the powerful engine noise? Here is a link from gearslutz which has a nice list of binaural or holophonic microphone set ups which more than likely would be the high end price-wise of what you are looking to do: http://www.gearslutz.com/board/remote-possibilities-acoustic-music-location-recording/493726-holophonic-vs-binaural.html
years ago we used Sennheiser binaurals (MKE 2002)  with a dummy head to make some live music recordings which may be useful in your situation: http://www.sennheiser.com/sennheiser/home_en.nsf/root/about_historywheel_history_1966

The SPLs of between 140- 160 dB may not allow for good binaural recordings, but they are/were omni capsules which should withstand higher SPLs than directional mics.

What about a jecklin disc?