Recording high audio levels with 151

R

Richy Lacey

Active member
Just had my first job since I bought a hmc151.
I was shooting a band at a music festival. For audio I had a Rode NTG2.
The audio levels were very high, so high in fact that I had to turn the level down to a few small notches above the minimum.

Once I'd done this the audio levels seemed to peak at -12db on the screen.
When I played back the audio at home the sound was awful. The audio is clearly distorting, despite what the display suggested.

I had the mic ALC set to on. Even with MIC ALC on the levels were still showing clipping. Is this normal?

Any suggestions as to how I can avoid such awful audio in future?
 
Richy,

Welcome to DVXUser.

Just to help you get started with this, there was much grousing about the 150 audio when it was first introduced. Essentially, the reports were much as you describe, extremely poor performance and or clipping while recording loud music. My recollection was this was mostly when the internal mic was used. Regardless, the 150 seems to have difficulty at high SPLs.

Suggest you look into a mixer with good limiters. Inline pads can also be added to reduce your SPL.

Try the search function and you'll get an earful since this was a pretty hot topic about a year ago.

Best Regards,
Grant
 
Any suggestions as to how I can avoid such awful audio in future?[/QUOTE]

Monitor with good headphones in a quiet place.
 
Thanks for the responses folks.

accelv said:
Monitor with good headphones in a quiet place.
Click to expand...

That doesn't make any difference when the camera simply can't handle the sound levels.
It's a design oversight on Panasonic's part, which may have lost me a few jobs already since I was unaware of it before shooting.
 
I wonder if the mic might be contributing to the issue?

I recorded this with (2) Audix I5 Mics, on a PA stack, one on the sub, one on the horn about 3 inches away. I had to turn down both inputs as suggested to about 1ish but I did not have any issues with clipping etc....


http://www.youtube.com/watch?v=ur3aWVBeeO0
 
Richy Lacey said:
That doesn't make any difference when the camera simply can't handle the sound levels.
Click to expand...
Or, more likely, it can easily handle the sound levels, and you were using the wrong mic for the job.

It's a design oversight on Panasonic's part, which may have lost me a few jobs already since I was unaware of it before shooting.
Click to expand...
No, it's a user error in using a condensor mic in a high-SPL environment. Use a dynamic mic next time and see if you don't get a thousand times better audio.
 
Hal2 said:
I wonder if the mic might be contributing to the issue?
Click to expand...
Almost unquestionably.

I recorded this with (2) Audix I5 Mics, on a PA stack, one on the sub, one on the horn about 3 inches away. I had to turn down both inputs as suggested to about 1ish but I did not have any issues with clipping etc....
Click to expand...
Right -- because the Audix I5 is a dynamic mic. Much, much, MUCH better suited to recording very high sound pressure levels.
 
Hi,

as Barry said - its often a question of the right microphone characteristic.

If i use a condensar like the NTG2 or the more expensive Sennheiser MKH416 in a club where loud music plays - there will be no chance getting an "perfect" sound... Especially Interviews cant be made with these mic's in such situations.

YOu can improve your Sound-Quality using dynamic Mics... i like the sennheiser MD421 / MD441 very much for use in clubs or even in a ice-hockey-stadium while the music is playing. I also often use the AKG D230 Reporter Microphone... .

I havent used the HMC150 because i just got mine a few days ago but heard of some problems with audio but i would use a headphone to listen the sound on location... .

Maybe u could use a "damping - element"... like a -20db pad adapter or something like that to get the levels of your NTG2 lower and have a more useful "area" of manual metering on the HMC.
 
Last edited:
85mk7 said:
Hi,

as Barry said - its often a question of the right microphone characteristic.

If i use a condensar like the NTG2 or the more expensive Sennheiser MKH416 in a club where loud music plays - there will be no chance getting an "perfect" sound... Especially Interviews cant be made with these mic's in such situations.

YOu can improve your Sound-Quality using dynamic Mics... i like the sennheiser MD421 / MD441 very much for use in clubs or even in a ice-hockey-stadium while the music is playing. I also often use the AKG D230 Reporter Microphone... .

I havent used the HMC150 because i just got mine a few days ago but heard of some problems with audio but i would use a headphone to listen the sound on location... .

Maybe u could use a "damping - element"... like a -20db pad adapter or something like that to get the levels of your NTG2 lower and have a more useful "area" of manual metering on the HMC.
Click to expand...


OK, dumb question, a pad will work even though there is no "power" to the I5? I would like to have a little more head room to play with. Will using the pad cause any issues? Would a -40db pad be "too much"
 
yes a -db pad will also affect dynamic mics like the I5 - even though i dont know that mic...

but a -40db pad could be to much for a dynamic mic in my opinion because genarally their levels are lower than condensar mic's.

On Mixers you otfen get -10db pad button... And -30 to -40db is often used do bring Line-Level to MIC-Level.

So i think -20db would be a good start for trying it with a condensar. It depends on the Mic and its ouput so i guess there is no general anwser what will fit best.

I'm not sure if there is a need to use such a pad with a dynamic mic.
 
Last edited:
85mk7 said:
yes a -db pad will also affect dynamic mics like the I5 - even though i dont know that mic...

but a -40db pad could be to much for a dynamic mic in my opinion because genarally their levels are lower than condensar mic's.

On Mixers you ofen get -10db pad button... And -30 to -40db is often used do bring Line-Level to MIC-Level.

So i think -20db would be a good start for trying it with a condensar. It depends on the Mic and its ouput so i guess there is no general anwser what will fit best.

I'm not sure if there is a need to use such a pad with a dynamic mic.
Click to expand...

Thanks, yea I had to keep the levels pretty low but still had some adjustment room so didn't know if it would be a good idea or not....
 
I've been looking at some of the pads suggested in the other thread.
The Audio Technica AT8202 has settings for -10, -20 and -30.

The only thing putting me off pads is the potential for loss of sound quality.

I should have had my Zoom recorder connected to the mixing desk so the awful audio is my own fault.
 
Hi Richy,

i'm using an SQN very often for professional sound mixing for ENG-Stuff and we send the ouput signal wireless to the camera (DigiBeta, Panasonic P2...).

We are leaving the SQN using the LINE-Levels and attaching an pad-cable to get the levels lower for use of our wireless system....

I havent noticed a quality loss in audio...

And even the SQN itself gives the possibility to -pad connected signals and it works fine without problems while giving you more flexibility in manually leveling the signal.

And yea.. recording simultanous to your Zoom will give u a nice Backup if something going wrong on the microphone/camera settings.. I also use it that way or even to simply get an clean Atmosphere sound even if my camera isnt running.
 
I was making a test recording in Brazil on a concert where the music was really stupidly loud, I got a head ache even wearing closed Sennheiser Monitoring Earphones, which by the way were great.

First I went to the back with my 150 on a Manfrotto Monopod, then I did set the camera Audio 1 (one) Notch over the minimum, ALC was ON.
Then I made a 4 channel recording with the Zoom H4N using a pair of Rode NTG-1 and I had to turn down the level to 2% for the Zoom mics and 3% for the Rode mics.
On all the mics I did use the foam windshield and I engaged a Lo-Cut of 80Hz.

The video was recorded with 720/60P and with F3 to get a vivid touch which was great except some white spots pushing out in the spotlight.
The audio of the camera was only used to synchronize the mixed audio from the Zoom.
At the end of the day I was really pleased with the result, even I got sharper images from my Casio F1, but also more bumped out highlights and an absolutely unusable audio. But I was able to mix the two clips.
 
Hi,
I've almost decided to order the HM-151 until I read about the audio trouble at locations with high SPLs. Since one of my main
application for the cam will be shooting fireworks and pyromusicals, which are loud in nature, I'm very concerned about this.

Going through this thread it looks, that its more a problem with external microphones either clipping itself or delivering too
high levels overdriving the preamp. Since easy portability of the cam is an issue for me, I plan to use the internal mic, how
does this behave in loud environments, also clipping issues ?

Another question that bothers me is, that there is no ALC obviously. Only some kind of limiter, which is activated in auto
audio mode. Does this mean the camera can do the audio leveling on its own or do I always have to worry about audio
levels ? How does this work out in practical use of the camera ? I'm afraid that this could be very annoying especially
if shooting alone on the run, already dealing with focus and aperture. What are your experiences about this ?

Thanks,
Markus
 
Eisbaer,

If you are intending to have professional sound, you will want to use external mics and or a mixer between mic and cam. A cam like the HMC-150 or really any cam that has pre-amps and phantom power will record decent sound; think basic stuff like talking head interviews. They lack the control to produce pro results in more difficult scenarios, especially so if you throw it curve balls like fireworks, loud music, or anything with varying or high sound levels. NO CAM IS DESIGNED TO GIVE YOU PRO AUDIO BY ITSELF. A good mixer will provide all the things the cam doesn't have; better controls, built in pads, better pre-amps, better limiters, and a bunch of other stuff to make your audio more flexible and sound better. See the link for a great location mixer. As a rule of thumb, you should be expecting to equal your cam investment in audio gear. Bitter pill but true. Crap sound will ruin your video.

http://www.bhphotovideo.com/c/product/292980-REG/Sound_Devices_302_302_Portable_3_Channel.html

Grant
 
ggrantly said:
NO CAM IS DESIGNED TO GIVE YOU PRO AUDIO BY ITSELF.
Click to expand...

Perhaps, but the DVX 100 takes such good audio that it is entirely usable for event work, even in such loud circumstances as a nite club band or wedding reception environment.

Will the 150 perform as adequately using the internal mic?
 
Jim,

I haven't owned a 150. I have owned a DVX100a, HPX170, and HMC40 and have recorded audio to all three. In fact when practical, I advocate recording to cam, with the qualifier that additional audio control is often needed.

Sound is a relative thing, what may be good enough for you is not for me, so to each his own. I stand by my statement two posts above that for anything approaching pro sound in a difficult environment, you need more than the pots on the 150 or any cam. Why do you think pro productions have sound people with mixers and thousands worth of gear? I think you proved the point with your original post, you aren't getting good audio despite turning the pots down.

One other thing you should check is the maximum spl at your shoot. The NTG-3 is rated for a max of 139db, but it probably degrades at a lower level. If your mic was in close to some real head banging, that could be an issue. Were you monitoring the sound with cans? What did that sound like?

Grant
 
I don't doubt the validity of using external audio on a pro shoot. I was asking about using the internal mics at an EVENT shoot, where mobility and automation are often very strong requirements, and "pro audio" is not.

I know the 170 has the same CCD as the 150. I don't know if it has the same mics and audio subsystem though. The 150 records only AAC, whereas the 170 records superior WAV files. I recall others claiming the 150 audio is not as good as the DVX100 (which was really very good for event work, and superior to many other DV cameras out there). I was just hoping to get some impression about the internal system of the 150.
 
You must log in or register to reply here.
Back
Top