redguitar

Thank you Zach!

Thanks! I'll check for this feature in the menu? Hopefully I can turn it off!

Hi, had the strangest thing happen today. While recording on 744t, I heard a delayed playback of the same recording, through the headphones. Also (and I'm not sure if this was always there and I've never noticed it), there was a headphone icon next to where it shows the channels (in my case 1,1) I was listening to. When I reviewed the files later, I did not hear the delayed playback in them. Any idea how I messed up? Much appreciated.

​Thanks Rich, yes actually of the two mics in the example I posted, one is set higher level than the other, and I do exactly what you describe above in post. But to take it step further, I need to find out if the 744t can make two recordings from the same mic, with one set at a lower db level. I've been using this feature on the Tascam DR60D to record "drive-by" exhaust sounds and really like it.

​Thanks, can you please elaborate on that? Are you saying I should record without clipping then boost the sound in post? When I've tried that before, the texture of the rumbling roar in the mid-freqs seems to lose impact. Sorry but I'm just hacking at this and trying to learn.

Here's an example of what I'm talking about. At the high end of the revs around the 5:18 mark, the exhaust sound gets a bit clipped. Past experience has been that if I use the limiter, it can sound almost corrupted or something — you can tell the limiter is struggling with it. If I don't let it clip, the 744t doesn't capture the meat of the mid-frequencies as the rev winds down. This is about what I consider just right. But I'm completely open to disagreeing opinions:

 

 

Thanks everyone, appreciate all the feedback & advice. My ears aren't exactly what they used to be, but I don't think I detect any pops, clicks, etc., just really loud "car music" that sounds like a guitar on distortion. But that said, I'm going to do further research based on the suggestions here. Thank you.

I'm working on a project that includes a cut of a muscle car screaming through a tunnel. We have several sound recordings to choose from. Some are just under 0db, and some are clipped. Honestly, it's the clipped ones that sound the best to me. I don't hear distortion, just BIG reverberating sound. And since playback will mostly be on mobile phones and computers, I want to make sure the sound IS big (it's a video for an automotive exhaust company, and sound is a big part of it). So my question is, is it ever ok to use a clipped sound? Recently I asked an audio engineer if the human hearing system has a limit and clips sound. He felt this was true. I was in that tunnel recording that car, and for me, the sound was so big and deafening that the only way I can reproduce the excitement of that moment in a video is to use one of the clipped recordings. I also suspect, without any proof, that if I were to analyze the soundtrack of a blockbuster movie DVD, I just might find parts here and there that are clipped. But I'm no expert and I welcome the opinions of those here. Appreciate your input. 

What's the recording situation? Dyno or track? That is really going to change the setup. When I've done cars on a Dyno I'll have easily up to 6 microphones on the exhaust, and they are placed anywhere from right on the pipe to 10 yards back. If the car is on the track then it's two, maybe three mics, mounted right on the car. My personal favorite on loud exhaust is the MD421. I'll usually have a 57 in there, and I always make sure I have a Sennheiser MKE2 Platinum thrown in there. It's a lav, but it sounds good when you throw high SPL at it. I've worked out a way to mount it right on the bumper (trade secret) and in engine compartments and wheel wells. If the car is on a Dyno then I'll pull out a Crown SASS-P and then I'll use just the "mid" of a Neumann RSM-191. Depending on the car I'll pull out a 416, and there's usually an arsenal of mics waiting to be used. Cars are very interesting to record and finding the sweet spot for mics is important. One area might sound bad with one mic, but you switch it out and all of a sudden it sounds wonderful. It really comes down to knowing how mics can perform in certain situations and which ones will give you what you want. I probably spend more time doing mic placement than actually recording because it is that important to get right. 

Thanks dfisk. Situation is track. I get the startup & launch, in-cabin, exterior (usually via bumper mics), and drive-by. I use SM58s for the startup & launch and exterior, a Sanken COS-11DBP for in-cabin, and an AT 4073A for drive-by. 

Thank you all very much for the input. I'm going to research all these mics now, probably pick up a couple and start experimenting. Speaking of experimenting, another option I'm going to try is a horn mic — the kind that gets placed inside a trumpet.

I record a lot of car exhaust, using a 744t with SM58 mics. Usually this combo works really well (at least I think it does, you can see a sample at https://youtu.be/ALQn0eTXttA), but sometimes the exhaust I'm recording has a huge bottom end AND a lot of high frequency sound as well. Since the SM58's seem to be optimized for mid-frequencies, I just can't get a full-bodied sound in those cases. Can you please recommend other mic choices that give me a wider range of recording capability, but can record really LOUD sound sources like the SM58's can? Obviously I'm not a trained sound pro, so please excuse any errors in my terminology. Appreciate any help.

" unless the reel sound sounds more like the real sound than the real sound recording does. "

right...

my class this morning suggested you could add the roar of a lion, to make it sound more organic!

Great idea! Packing a rope and some prime rib now and heading to the zoo...

This looks interesting

Mic nose cones...

" I wish there was an auto-gain feature so as the car pulls away the sound doesn't fade so fast). Re: shooting out the back of the camera car, the sound you hear in that Mustang vid was actually from a rear bumper mic (SM58). "

so, you are manipulating the sound to tell the desired story...

like I said: reel sound vs. real sound.

Yes, however, we'd rather pursue ways to get the real sound, unless the reel sound sounds more like the real sound than the real sound recording does.

3) car to car is the one requiring more planning because you don't want to hear the camera car, but need to keep up with the picture car making some use of the engine. Some sort of shotgun, or long shotgun mic would *probably* help avoid the camera car noise (if it has quiet exhaust), but you are potentially heading into hurricane level winds. I watched the video for the Mustang GT and the car-to-car was out the back of the camera car, so in a case like that, the camera car would probably provide a way to block the massive wind. That would give the "this is what I sound like to you as I come up behind you" perspective.

Thank you for all your great points and yes you've nailed the challenges and optimum recording scenarios of what people want to hear (another one is the vehicle "launch," and that one's fairly straightforward, although I wish there was an auto-gain feature so as the car pulls away the sound doesn't fade so fast). Re: shooting out the back of the camera car, the sound you hear in that Mustang vid was actually from a rear bumper mic (SM58). I've tried recording from the camera car but wind noise was overpowering. One thing we haven't tried is a full Rycote system from rear of the camera car, I wonder if that would work. Something to try next time!

" the true exhaust note "

" Sometimes the sound from a GoPro (or heck even an iPhone) can be better than the "pro" sound, "

I still believe you are dealing with subjectives...

Absolutely. That's just my impression of course.

Another thing to point out is that re: the suggestions in other threads to use an axle dyno, the problem with that is the engine is not "under load" and the sound is not true. So we're faced with our arch-enemy the wind....

" an accurate-as-possible reproduction of what the exhaust actually sounds like, "

OK, I watched the video, but there is still a lot of subjectivity and "it depends"...

I can easily think of loads of different sounding possibilities: like POV... what does it sound like in the driver's seat (are windows up or down?) or when it goes by someplace (and the place will play an important part in what it sounds like)

mic choices, mic placements, and many other variables will be a part of the final result, and then of course so will the data compression schemes of transmission, and the audio capabilities and performance of the individual playing the clips...

In fact your very question beg: are you looking for the most accurate sound reproduction (whatever that is) or the best sound reproduction (whatever that is!) ??

Yes, this is the crux of the challenge. The variables are many, exactly as you say. And a huge factor is of course wind noise, and how to tame it just enough to avoid changing the true exhaust note too much. We're always experimenting with mic placements, custom-made aerodynamic housings (different for each vehicle), and many other factors. Sometimes the sound from a GoPro (or heck even an iPhone) can be better than the "pro" sound, which is frustrating. I think the auto-gain feature in these cheap alternatives can work very well for the ever-changing volume level of a car exhaust.

Please keep in mind a lot of what I say is just the best way I know how to say it at this point. I'm not an audio pro (which you undoubtedly figured out after my first post!). I've hacked at it for many years, worked with pros, but my spot has been behind the camera, along with scriptwriting, lighting & editing. I'm trying to get serious about learning the audio trade because often we have an extremely small window of opportunity to record the exhaust sounds, and we can't get always get a pro to come out. All the help here is greatly appreciated!

Thanks Jim, I had seen that thread and found it very informative. Senator Mike, since these videos are aimed at consumers who want an accurate-as-possible reproduction of what the exhaust actually sounds like, our focus is on the "real."

Thanks everyone for the great input. Marc Wielage, I will get those books.

Hi, I'm new and appreciate this great resource and the people here. We shoot a lot of automotive performance videos, and the biggest challenge is recording accurate exhaust sound. I found a great thread here on the subject, but I also want to ask if anyone can recommend any books, online courses, or even "brick & mortor" classes (if in L.A. area) that would help me learn and expand audio skills, especially for this exhaust challenge.

One book I found that might apply is Recording Music on Location by Bruce & Jenny Bartlett. I figured the dynamic range of an automotive exhaust was similar in many ways to a concert. But I am sure suggestions from the pros here will be much more applicable.

It might help to show an example of what we typically do.

the link should go to about 4:55, where a particularly loud exhaust is featured.

I greatly appreciate any help!

- Chris