View Full Version : recommend amic for recording exhaust/engine sounds


Syeed Ali
July 9th, 2012, 02:26 PM
Can anyone recommend a microphone that I could stick to the back of a car to record the exhaust sound?

Must be small and good quality and not to expensive.

Thanks

Jon Fairhurst
July 9th, 2012, 03:54 PM
I'd recommend a Shure SM57.

Shure SM57 - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Shure_SM57)

You don't need a high-fidelity mic. Most anything that can handle the noise level will work.

I've done this before. I put the mic off of the exhaust axis by about 45 degrees up and to the side. This was to keep smoke and spittle off of the mic as best we could. The mic was pointed straight at the tailpipe. I think the distance was about one foot. We just revved the throttle, did fast and slow accelerations, and held it steady at varying RPMs. I think we recorded about three minutes of content and made it match the video in post.

As I recall, I had to be really aggressive with EQ to get a beefy enough sound. I heavily scooped the curve and boosted around 200 Hz strongly. Engine sounds pitch shift really nicely too. Racing games use a very short loop and adjust the playback speed as needed. Works great!

Changing the EQ and panning of the engine sounds depending on camera position works great too. Give it more volume and highs from the rear. Muffle it slightly from the front. Muffle it strongly from inside the car.

Best of luck!

Christian Brown
July 10th, 2012, 05:23 PM
Audi Sound Studio - What is the Audi sound? - YouTube

You will get better results with a better microphone. Consider the DPA 4060. You can tape it to the bumper.

Jon Fairhurst
July 11th, 2012, 12:09 PM
Great video!

One funny thing is that at 0:49 they show a shotgun mic in the engine bay as they play the sound of an engine revving. Clearly, they didn't playback this sound. A mic in the engine bay mainly hears belt and valvetrain sounds, and maybe a bit if intake sucking. It tends to sound like a squeaking bucket of bolts. Yet, the sound they play has a strong exhaust note.

While the DPA 4060 is no doubt a great mic, it costs about $1,000. The original poster asked for "not too expensive." It's also an omni, which wouldn't be ideal. Taping it to the bumper is easy, but it would lack adequate wind protection when driving.

In my project, we just put the mic on a stand and revved the engine while parked in a semi-remote area. Recording in stereo would have been nice. I just panned the sound as appropriate. If you can do stereo, go for it. You'll get a larger sonic image in stereo.

But the bottom line is that an engine exhaust is a raspy, distorted sound. We're not recording a human voice, violin, or even a signature sound for a particular model car. We generally want a believable sound for Foley and want it to have a powerful sound for certain scenes.

The SM57 has been used to record electric guitars on thousands of albums. Studios with a cabinet full of thousand dollar mics will often grab the SM57 to place in front of the guitar amp. What could be more similar to recording an exhaust pipe? And you can get one for about $70.

As I wrote earlier, the key to getting the right sound is EQ. You can make it sound powerful, wimpy, or muffled depending on your needs. As long as the mic has a reasonable frequency range and doesn't clip at high volumes, your source sounds will be adequate. Just don't expect it to sound big and bad without EQ, regardless of mic quality.

If you want to record while driving, the challenge won't be the mic but the mount and wind protection. As shown on the video, a suction mount, Rycote blimp, and shotgun mic are the right choice for that. But on a budget, an SM57 on a stand is the way to go.

Kevin Walsh
July 11th, 2012, 05:34 PM
Does anyone know what mic clip is being used in the picture of the President on the SM57 Wikipedia page. I have been looking for a dual mic clip like this.

Rick Reineke
July 14th, 2012, 08:42 AM
SM57 VIP Dual Microphone Kit
Shure Americas | SM57VIP Dual Microphone Kit | Instrument Mic, Rugged, Touring (http://www.shure.com/americas/products/microphones/sm/sm57VIP-dual-microphone-kit)
The A2WS and A81WS windscreens are not shown but are included.
"Used by every presidential administration since Lyndon B. Johnson"

FWIW, the 57 is often the go-to mic for snare drum and used on millions of recordings and many many hit records.

Kevin Walsh
July 16th, 2012, 12:47 PM
Thank you!

Colin McDonald
July 16th, 2012, 02:31 PM
The SM57 has been used to record electric guitars on thousands of albums. Studios with a cabinet full of thousand dollar mics will often grab the SM57 to place in front of the guitar amp. What could be more similar to recording an exhaust pipe? And you can get one for about $70.


As a (albeit now retired) musician to trade, I concur.
Vorsprung durch Bulls***

I would dearly like to hear how even a full Rycote Windjammer kit copes with the airflow round a sports car driven at high speed.

Great video, though.

Jon Fairhurst
July 16th, 2012, 03:42 PM
I'd also like to know the speed limit of a windjammer. As mentioned earlier, I didn't even try. The driveway approach worked quite well for what I needed.

One last word: Fahrvergnügen. :)

Tony Koretz
July 17th, 2012, 02:24 AM
The sound from an exhaust is quite different from an engine under load ( ie driving) than one that is stationary. Probably a good idea to record both, as well as engine mics if possible to cover various scenarios too. There is a pretty good bunch of information on this site that you may find helpful. I had it bookmarked myself so I could find it again:
Rob Nokes Special: Guide to Recording Cars (http://designingsound.org/2010/08/rob-nokes-special-guide-to-recording-cars/)

Jon Fairhurst
July 17th, 2012, 11:13 AM
Great article!

And, yes, there is a difference between the exhaust sounds in the driveway and when accelerating on the road. If you floor the accelerator in the driveway, the engine will be "full throat", but within a second or so, you'll be at redline. On the road, you can floor it and record a more natural acceleration.

On the other hand, when cruising, even at freeway speeds, the throttle is only part way open. Unless you're at high speeds or going up a hill, the sound in the driveway is pretty representative. As mentioned before, EQ is a hugely important tool.