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Getting decent video audio on your Seven


Croc

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Getting decent video audio from GoPro or other types of action cameras

 

I have started this thread as lots of people ask me how to get decent sound in a seven while on road or on track. I am not sure I am any better qualified to answer but I have done a lot of experiments to form an opinion as to what I think works. Of course opinions are like assholes – everyone has one and quite a few people have two!

 

I am not going to cover which is the best camera or mounting systems in this thread – just want to focus on sound. I personally want a good throaty engine sound in my videos, nothing annoys me more than seeing a great video with some crap music overlaid. I want to hear that engine roar at revs. If you are like that read on. If you prefer crap music then stop reading now.

 

I am not an audio engineer – I just know what I like listening to in a sevens driving video and there seem to be enough sensible enthusiasts on here who are similar to me in what they want out of a sevens video for sound. I am an anal personality (very appropriate being an accountant/actuary) – I am trying for high quality sound – some of you may agree with me and others may want to short cut. All of us are right – we deserve to get what we want.

 

Klasik and Kitcat expressed some desire to know more about my sound research on videos – not quite sure why they ask me – I could f$%^ up an erection! So this is a practical approach for the average numpty like me.

 

A seven has unique acoustical properties:

- They are aerodynamically dirty so lots of wind noise is a given.

- They have a light construction so they transmit more vibration, noise and even electrical interference.

- The light construction can sound “tinny” instead of resonating a nice deep note that a regular car might do with its more enclosed and insulated spaces.

- They have lots and lots of wind noise….did I say that already?

So this is a challenge that even open wheel race cars don’t really have as most of them have slippery aero bodywork that can hide microphones unlike a seven.

 

Many of the video examples below are illustrating the sound changes with the different methods. Don’t listen to the whole thing – listen just enough to get a sense of what works or does not work.

 

So let’s start at a baseline. The GoPro or any numbers of action cameras advertise fantastic sound quality out of the box. That might be so when you are surfing, horse riding, riding a mountain bike, rock climbing or running around with your girlfriends during a tampon advertisement. However that is not true when you stick an action camera into a seven and ask it to record a spirited drive or track event.

 

For example here is a GoPro HD2 without external mic in its regular waterproof case perfectly mangling the glorious tones of a beautiful BDA engine in this gorgeous Caterham:

 

GOPR1922 - YouTube

 

Hmmm…. So that sucks! But what if you move the GoPro from the roll bar down to a more sheltered position in around the scuttle, just behind the aeroscreen?

 

GOPR0191 - YouTube

 

Actually that is not too bad. The position seems to shelter the camera from the worst of the air turbulence noise.

 

Lesson 1 – Position the microphone out of the wind.

 

So let’s try and use an external microphone and see if that improves matters? Just a simple Olympus ME-52W connected to a POV VIO HD camera with the mic under the canvas tonneau in the boot area:

 

 

 

 

Not great. The mic is overpowering the ability of the camera to process the intense noise frequencies. So with exactly the same mic mounted in exactly the same position let’s try it with a Go Pro HD2:

 

 

 

 

 

Well that’s better. Still a little soft in volume and too much wind.

 

Lesson 2 – Some cameras are better than others at processing recorded sound.

 

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Somewhere around this point in my discovery I read lots of techie type articles about how you need a powered microphone to improve dynamic range, improve gain and possibly score on a Friday night. Well maybe not the last one but it got your attention. So I graduated to an AT-3350 lavalier omnidirectional microphone. This has a little battery within it. So let’s mount it to a GoPro and locate the mic under the rear tonneau in the boot area.

 

 

 

 

Much better. Much more differential noise than I would like – whines like Yellowss7 on this forum. Still some wind noise. Not as throaty as the engine sounds in real life – a little thin sounding. Still not a great recorded representation of the sound we hear from our cars.

 

Lesson 3 – Power is better than no power when using a microphone

 

So now I thinking I need to move the mic around to find a better position within the car. Positions tried and discarded:

- Under the passenger and driver’s seat – too much wind noise

- Under the dash on the center tunnel – too much wind noise. I guess air flow rolls off the dash and circles under the dash and foot well area?

- On the rear wing in front of the exhaust tip – way way way too much wind noise even with a dead cat cover. A dead cat cover is a furry item that covers the entire mic tip and is intended to protect the mic from hearing the wind. In that position, I would probably found a dead pussy to be more effective than the mic cover.

- Mount the lavalier mic to the exhaust tip using painters tape. Totally blonde move from me. Burned the tape, melted the mic, recorded nothing worthwhile and I felt like a right muppet.

 

After hanging upside down in my passenger foot well like an overgrown bat I saw a nice ledge way way up under the passenger side dash where the relays are located. So I gave that a go.

 

I also upgraded mics to a demo model of an AT689 that I… errr….borrowed (and broke…oops!). This is an expensive powered mic (about $160 from memory – now superseded). I do not recommend trying this at home.

 

 

 

 

Much better. No wind noise now but because it is next to electrical components and it is unshielded you get static and interference. You also can hear the cycling of the fuel pump relay if you listen carefully. So that is another fail.

 

Lesson 4 – Sticking your mic next to electrical components in a car will likely get some static/interference noise.

 

I do learn that a better quality microphone will produce better sound recording results – you get what you pay for. From my direct phone discussions with the Go Pro tech people on how they produce their videos I learn that they frequently use a Sennheiser MKE400 or in one case a Rode Video Mic. Both are $200 area each. They also admitted they have used from time to time separate digital sound recorders to blend sound into the sound recorded by the camera. More of digital recorders later.

 

Lesson 5 – With microphones you get what you pay for

 

So let’s try the same mics and locations in different cars of different USA7s members to see if I can replicate the results consistently. All of the following are done with two AT-3350 mounted in the boot area under the tonneau using GoPro HD2s:

 

No

 

http://www.youtube.com/watch?feature=player_detailpage&v=OFXx0S3UucM#t=639s

 

 

Yes

 

 

 

 

 

 

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Consistency is damn near impossible. I installed all of these mics using the same technique I tried on my car and I get an overall fail rate. Some issues driving the problems are:

 

- Vibrations making the mic to camera and internal mic connections break.

- Flat battery in the AT-3350 (no idea how long the battery lasts – I seem to get 1.5 days continuous track time from my testing at NJMP but it always go flat when I really want to rely on it).

- Forgetting to turn the on switch on the AT3350 (no excuse – shoot me!)

- Vibrations eventually killing the mic so that it no longer records (internal fault to the case or some break in the mic wire?). Been through 3 this way now.

 

It is very difficult to work out at a track or during a drive whether you are recording good sound or not. There is no effective way to test this out in the field. Easily done on a laptop though.

 

There is no excuse for the errors I made – I was the biggest tool in the kit. Keeping it simple is important as you have a lot to remember to coordinate when you are about to go on track (helmet, gloves, belts, camera, fuel, mic turned on, bonnet clipped down, etc.

 

Lesson 6 – Just when you think you know something you get taught you know shit! Try again.

 

With all this frustration I needed a cure.

 

Lesson 7 – Alcohol can improve your attitude.

 

So now I try for the Holy Grail. I give up on the cheap but fragile AT3350 and I run the AT689 mic forward to the engine bay and (painters) tape it to the shelf above the passenger foot well. The metal in theory should shield the mic from electrical interference and I should get lovely throaty sound from the roller barrel throttle bodies. Recorded with a GoPro

 

 

 

And so it works. On back off I do get a tinny (another technical term of my making) sound as the intake is closed off but the rest of the sound is perfect. I even hear the CR500 tires being bitch slapped through the corners.

 

Lesson 8 – Engine bay on the intake side can produce really good sound with an external mic.

 

So now can I replicate the sound using different mics same location? GoPro HD2 paired with either an Opteka VM2000 shotgun mic or an AT Pro-CM24 shotgun mic.

 

Opteka mic

GP010002 - YouTube

 

AT ProCM24 mic

 

 

Success!!! Both are Zetecs of relatively similar horsepower running the same day and on the same track. The only difference in mounting is that the AT Pro CM24 was mounted drivers side above the pedal box on the Caterham.

 

The Opteka was mounted above the passenger foot well under the bonnet of the SPF S1. The AT Pro CM24 sounds best to my ears.

 

As a contrast here is the Opteka taped to the inner scuttle above drivers knee – not bad but a bit rattly and more wind noise than I would like. Would prefer just engine noise/exhaust noise.

 

 

 

 

Lesson 9 – Engine bays are a good location for microphones as wind noise is largely minimized and intake sound is pretty good

 

Lesson 10 – Have a drink as a reward at this point.

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So now my question is does it work with other cameras? Yes – tested the AT689 with the Drift HD Ghost and the Braun Six Zero with mic mounted up under the bonnet above the passenger foot well.

 

Braun Six Zero and AT 689

 

 

 

 

 

Drift HD Ghost

 

 

 

The Drift camera is not quite as good as processing sound as the Go Pro or other cameras with an external microphone. It picks up the deeper intake notes but seems to have trouble with the higher pitch notes once the intake is closed. Seems like Lesson 2 holds true.

 

Lesson 11 - Some level of testing is required to make sure these solutions work on your seven. There is no out of the box solution for a seven

 

So then I tried separate digital recorders, both mounted in the cockpit using the screw clamp mount. The first tried was a Tascam DR05 and the second was a Zoom H1. Most professional videos will use a separate recording source rather than use a mic attached to an action camera. This makes sense when you think about it as a digital recorder of sound is a complex piece of equipment, larger than the action cameras we are using. So its dynamic range, sensitivity of mic, noise reduction, and general ability to record a good track is always going to be better than the comprised equipment contained within a tiny GoPro box or the like.

 

The one big downside with these is you have to spend time post production synchronizing video with sound (either with the regular video editing package or an application like Race Render. When you start recording you would clap to get a visual and aural cue from which to base the synchronization

 

However, I found the vibrations from the car killed both the Tascam and then the Zoom H1. They would turn themselves off or just not record. So they were returned for refunds.

 

Lesson 12 – Digital recorders offer the promise of better sound recording but more stuff to fuss with to record and sync with video later. Better to keep it simple.

 

What sounds good to me does not sound good to others. Being a young stud on this forum I prefer a little more bass in my sound mix. Others prefer a little more treble when they hear their car recorded using my equipment.

 

Lesson 13 – Sound is a personal thing. You may not like what I like – so experiment.

 

This is my view on getting decent video sound on a Seven drive or track day. I don’t profess to know all the answers so please constructively contribute with details and examples of what you think works well for mic position/location and equipment used.

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Jezz, Croc, highly impressive effort. I dont want to think abt the time commitment it took.

 

I was very happy with the sound I got from the way you set up the GoPro on my car at last NJMP w/mic under bonnet taped down by steering column.

 

I was also happy w/my own earlier set up, where I put my self powered cheapo mic (since expired) in a large wool sock and folded into a ball and taped it to the floor of the passenger side of the car.

Edited by Kitcat
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Wow, what a great.............no, FANTASTIC lesson on audio recording with a 7. I really got a kick of some of your technical explanations, like "dead pussy". I googled on Amazon.com to see if I could buy one inexpensively and they just don't list them. Must be a regional item :hat:

 

Ok, so now I'm on the hunt for a ProCM24 mic. By the way, do you have a $24 million budget for testing this stuff ? I can only admire your determination to find the perfect solution.

 

Question: Were you totally friggin drunk when you taped the mic to the exhaust or did you do this while somewhat sober ? I don't have room to talk as evidenced by some of my videos with the sound of............well a Eureka vacuum cleaner running on 220 VAC.

 

I never would have thought of puting the mic in the engine compartment but I have to admit it is brilliant, and very logical. What are we trying to record ? The sound of the engine of course, so why not put the mic close to the engine.

 

I can't thank you enough for taking the time and incredible effort to lay out all the possibilities, post the results, and explain how and why. I can't speak for the others but I can vouch that I would have given up way before coming to the conclusions you did. You must be in the electronics business. Absolutely BRILLIANT presentation.:cheers:

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Since Croc went to all this trouble for us, I thought I'd help a little by listing the mics and their prices;

 

Opteka VM-100 with mount and hairy cover......$19.99 + shipping

Audio Technica ATR-3350 Lavalier...................$19.91 + shipping

Audio Technica PRO24CM Stereo with mount.....$61.22 (free shipping)

Olympus ME-52W noice cancelling mic..............$26.94 + shipping

 

All of these were from Amazon.com some were in short supply. And of course, the one that gave the best results is the most expensive of the group. I think it's the only one that records in stereo mode as well.

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I think I was referring to dead pussy as dry humor for a cat that has expired. However, there are things for cutting wind noise on microphones called dead cats or dead kittens - here for example:

 

http://www.amazon.com/Rode-DEADKITTEN-Dead-Kitten-Windscreen/dp/B0017JHU10/ref=sr_1_2?ie=UTF8&qid=1374693858&sr=8-2&keywords=dead+cat+windscreen

 

They actually work quite well although I have lost and burned quite a few through my experimentation. :o I prefer the ones from www.windcutter.com as Rebekah the owner has been very helpful in providing advice.

 

Much of my equipment was loaner from various suppliers and connections with me being a journalist reviewing the equipment for a newletter (and I did write articles). More than once I have returned equipment in a non-operative condition and escaped punishment. The cameras are all this way although I have since bought the Braun SixZero as that is one brilliant little camera and my GoPros are slowly dying off. I also bought some used (as new) microphone equipment on Amazon or Fleabay and saved a packet.

 

I was not drunk when I taped the mic to the exhaust - I was having a blonde moment. Yellowss7 and Blubarisax were on track with me that day and luckily did not notice. :redface:

 

Me in the electronics business? Nah! Just a boring little accountant/actuary

 

The AT Pro-CM24 was mounted on Mike's (Kitcat) car. Really just taped down the mic to the aloominum with painters tape so it could not move or rattle leaving the foam covered microphone exposed. We removed the stand thing that it came with. The wire from the mic to the camera was also run along the side of the car and up the roll bar to the camera with painters tape holding it temporarily. A little more thought could make a neater permanent solution.

 

When pricing on amazon, look at the "More buying choices" options. They have the items cheaper again.

Edited by Croc
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Anyone have results with a Replay XD1080? I have one and am happy with the video quality and the camera’s user-friendly features, but sound quality is an issue . . . yep, it pretty much sucks. I have the Replay lavalier mic and have tried several different locations with no good result; have not tried under-hood yet, but have considered this option. Willing to try another (better) mic with this camera, but not sure what will work. Guidance appreciated.

X :willy_nilly:

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I have not tested the camera but looking at the external mic and its sound specs I can get a sense of it being comparable to the Crocolis camera I have used. The Replay external mic is a variation of the AT3350. Powered are powered mics using the LR44 battery.

 

Given the very compact size of the camera I would not be surprised if you have inbuilt compromizes on the ability of the camera to process sound recordings from demandingly loud environments.

 

My suggestion to improve matters would be:

 

1) get a 3.5mm extender cable (3.5mm male end and a 3.5mm female end) that will allow you to go from the camera back to the engine bay. These are cheap.

http://www.amazon.com/iMBAPrice-iMBA-PS-06MF-6-Feet-Plated-Extension/dp/B009UEBQIM/ref=sr_1_3?ie=UTF8&qid=1374699424&sr=8-3&keywords=3.5mm+extension

 

2) Place the Replay mic in the engine bay somewhere out of the way where it cannot be eaten, burned, fried or otherwise destructive in rapidly rotating belts. I tape mine down to be sure. i am assuming that the end cap shown in the Replay XD external mic kit can be removed for this?

 

3) Give it a test.

 

4) If that test shows wind noise then look for a mini windcutter dead cat/kitten/pussy to mask the wind and try again.

 

5) If the test in 3) does not reveal wind noise but shows that the mic cannot handle the sound - breaking up, distortion, hoover noises, etc, then you have an issue with the mic. Maybe start cheap and try the AT3350 first as a replacement. Its a good little mic for the money but I just found they would break on me. Admittedly I am using them in a very demanding automotive environment!

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I have used GoPro cameras for years and always laugh at the "over 100 MPH use closed case" note, more like "over 40 MPH just give up", (see cheezy music note posted by others).

When the Hero2 came out I jumped on it and after a few trys have had good luck (in an S2K) with stereo mics, one inside the passanger footwell deep under the dash for motor and one mounted in the boot for rosd sound, both with a dead pussy covering it (see great post by others).

I do have to admit that my loose suspension sounds like a cheap coffee can and pebbles percussion group till the car comes up to speed but then you get some good tire noise.

Don't remember the brand but non-powered and about $75 bucks for the pair. Haven't had any problem with headroom on the unpowered mics. GoPro does have a limited power supplied to the mics so you don't need to supply an outboard power unit

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Most of the usual mics (nowadays typically electret condensor mics with or without preamp) just have trouble with the decibel level. They are not made for that and distort the signal already, then still output high volume signal into the recorder which may distort it even more before it gets in to the AGC stage.

 

I had moderade success with an old fashioned passive dynamic microphone from Radioshack. This normally needs a mic preamp but with a 1:4 audio transformer I just routed it directly into the camcorder (I used a Contour HD with hacked electronics for a remote mic) and slid the mic behind the driver seat. Somewhat decent volume (usually needed some boost when editing), good exhaust sound but in that position also some suspension click/clack and wheel noise on uneven pavement.

 

However, I have given up video recording for the most part. I still have unedited video from 6 years ago and don't need to add to that....

Edited by slomove
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Regardless of quality, I find the soundtrack very instructive as trackday driving feedback. I can hear myself lift off the gas in the fast corner where I wld swear on a bible I never lift, hear the motor tail off way before the corner that I thot I was charging up to, hear myself get on/off the trottle in places where I shd be smooth. If I compare my "sound" to a fast driver on the same track, I can "hear" where they are faster.

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Well the JVC will not help you as that does not have an external mic option. At least it did not in its just superseded version. And I never saw a good review on its audio. Not sure if the new release for late this month does have an external mic?

 

Xcarguy on here is working with a Replay. I like the small size but it seems to have audio processing problems from the youtube I see of his but that could be because of operator challenges?

 

Never tested a Contour but someone else here probably has.

 

I rank the GoPro (HD2 for me) marginally over the Drift HD Ghost for sound capture using an external mic. The HD2 captures very noisy environment (i.e. our cars) much better without distorting. The GoPro Black/Silver are supposed to be better again. The same mic was used in my back to back testing. This is a marginal win in my view as they are pretty close and I am being fussy in my evaluation.

 

However, the Ghost is a much better package design overall - all in one design makes it much cheaper than a GoPro Silver where you have to buy all the options (eg, viewing screen). The swivel lens is very helpful in getting upright images without ball head mounting adapters. Also a very helpful customer service function. A GoPro Black will beat the Ghost easily for quality but at what cost?

Edited by Croc
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Xcarguy on here is working with a Replay. I like the small size but it seems to have audio processing problems from the youtube I see of his but that could be because of operator challenges?/quote]

 

I am using the Replay XD1080 HD and have only had it in hand since April, so I’m fairly new to the camera; Croc, the rear cap on the camera is removable.

 

After researching cameras, I chose the Replay for its simplicity and size. The video quality is superb (my humble opinion) and the camera programming can be manipulated to suit the needs of the user. For example, I have reprogrammed y camera for an external power application. When I plug the external power cord into the power outlet in my car, the camera turns on and automatically begins recording. When I remove the external power cord from the power outlet the camera will record for an additional 60 seconds and then automatically powers down; a great feature if you are strapped in your car and have your camera located where you can’t easily reach the ON and RECORD buttons.

 

Dialing in sound quality has been my nemesis thus far; and, my ‘operator challenges’ :willy_nilly: haven’t helped. The Replay comes with small ‘stick-on’ windbreakers that you affix over the mic hole to suppress wind noise. During my first track day with the camera in April, I placed one of the windbreakers in the wrong place on the camera (mic wide open to the wind). After watching the first video, I rechecked the camera and discovered the misplacement of the wind breaker—operator error. The wind noise on the videos was so horrible that overlay music was the best/salvageable option.

 

After this adventure, I place the windbreaker correctly over the mic hole and went for a test hop; this too proved fruitless. It suppressed the wind noise to an extent, but it also suppressed the engine sound I have ‘yet to date’ to capture. I then ordered the Replay external mic and picked up a foam windsock at the local music store. Several test hops later (and several different mic locations) and I still wasn’t happy with the sound quality. I tried behind the seat (high and low positions). I even tried running a hollow flexible tube (plastic electrical conduit) down to the exhaust tip; ran the mic down the tube and still, no good sound quality.

 

During my next track day, I placed the mic underneath the dash. At the end of the day, I discovered that I never turned on the mic (:cuss: AHHHHHH!!!!!!). The second batch of videos I posted (6//1/13) are shot with the Replay windbreaker placed over the mic hole. To date, I haven’t gone out and done a test hop with the mic placed under the dash AND TURNED ON. Once I run an under-dash test hop, I’ll report back on this thread.

 

My last resort with the Replay mic will be to place it in the engine bay; I also may try a different windsock. However, this may be a problem area as well due to the sides of my engine bay being open and exposed to the wind. We’ll see. :ack:

 

X

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Hello. My name is Jeff, and I've been a lurker of this forum for a while as some day I hope to be a 7 owner.

 

I've been reading this thread, as I too have been playing with POV cameras. I thoroughly enjoyed reading Croc evaluation of different cameras.

 

I drive a BMW Z4 M coupe in autocross and track events. I have the Replay XD 1080HD, and like xcarguy I love the video quality, but it was a challenge to get great audio quality. I too found the windbreakers not to solve the wind noise issue. I got the Replay external mic, and tried it in all different positions. The best location I found is in the engine bay, and the second best is with the microphone clipped on the rear license plate pointed towards the exhaust.

 

Here are some examples with the microphone mounted in the engine bay (gain setting at max 59 dB):

 

And on the rear plate:

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