.wav sound problems

H

hgher

Member
Hi guys, I'm not sure what's up with my sound files and no one I've asked seems to know how to fix it.

They were recorded on a zoom h4n and I can hear them perfectly fine in Adobe Audition / Audacity / Foodbar2000 with headphones on or Stereo speakers but when I try and and use 5.1 suround or if I import the wav file into Media Composer I get a very low frequency tone with the sound very muffled in the distance. I've tried exporting the file via Audition and re-encoding it to other formats but the issue persists. I'm hoping this is something easy I've overlooked and it's driving me mad trying to figure it all out :Drogar-BlackEye(DBG, would really appreciate some advice here! I've uploaded two of the files to my dropbox:

https://dl.dropbox.com/u/9627044/00-mugb.wav
https://dl.dropbox.com/u/9627044/00-eggsfry_01.wav

(edit text color)
 
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What does "try and and use 5.1 suround" mean? What exactly are you doing? What are you trying to accomplish?

HOW were they recorded? With what microphone(s)? With what cable(s)?

(PS: Black text on gray is very hard to read.)
 
Thanks for the response Richard, I'm sorry about the black text - I copy/pasta'd from my Facebook group.

I'm trying to import and sync these sound files to footage I shot on the same day, these were recorded with a Sennheiser 816 shotgun mic connected to 1 channel on the zoom h4n. I'm not sure what cables were used.

My issue is that the sound files play fine using most programs and as long as I'm only using 'stereo' output, but when I import them into Media Composer 6 the sound is barely audible or plays a series of low frequency 'fuzzy batches'. I reproduced the same problem when playing the audio through 5.1 surround speaker output.

Sorry if I'm not being technical enough, the film was for a uni project and it was the first time we used the h4n - or recorded audio separately at all. We did test the sound in the h4n and I know our sound recordist controlled the level, so I'm hoping the issue is more with our post workflow. Still trying to learn it all :/

A friend did a media info grab of one of the files, if that helps:

General
Complete name : \Downloads\00-eggsfry_01.wav
Format : Wave
File size : 4.10 MiB
Duration : 7s 452ms
Overall bit rate mode : Constant
Overall bit rate : 4 616 Kbps
Producer : ZOOM Handy Recorder H4n
Encoded date : 2008-02-21 06:36:32
Encoding settings : A=PCM,F=96000,W=24,M=stereo,T=ZOOM Handy Recorder H4n

Audio
ID : 0
Format : PCM
Format settings, Endianness : Little
Codec ID : 1
Duration : 7s 452ms
Bit rate mode : Constant
Bit rate : 4 608 Kbps
Channel(s) : 2 channels
Sampling rate : 96.0 KHz
Bit depth : 24 bits
Stream size : 4.09 MiB (100%)
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OK my friend also suggested converting the file type to MONO in Audition and exporting it again. Its working now and I feel like an idiot for not thinking about this earlier.
 
Your first sample is almost too quick to discern anything. Almost. After listening to the egg frying, I can hear the problem in both. You have phase cancellation, which means that one channel somehow had its phase reversed (meaning + and - signal flows were swapped). It actually sounds terrible with stereo playback.

So a Sennheiser MKH-816 was used, but recorded to both channels (1&2 or L&R, however you'd like to look at it). I wonder how that was done. Since the H4n encoded it as a stereo file, it wasn't done by using the internal "mono mix" function. If it was accomplished by using a splitter cable, it's possible (likely) that one side of the cable is wired differently from the other.

How are you converting to mono that you're "resolving" the issue? Since the original source material is mono (the 816 is not a stereo mic), your best bet is to split the stereo pair and ditch one of the playback channels in whatever program you're using.
 
Thanks for the response Alex. I've gone through and extracted the channels to separate mono files and as you've said ditched one of them for two copies of the other in a make-shift stereo file. It's not the idea solution and certainly not 'resolving' the issue (whoops), but it's the best I can do for now. I wasn't the sound recordist on the project so I'm not sure how everything was connected or which cables were used, but when we tested the initial recordings it played back OK on headphones. I'm hoping to salvage any sound I can get out of these files and so far it's going OK with the 'work-around' I've ended up adopting, I'm not 100% satisfied with it but my team abandoned the project before completion and I've had to pick up the pieces to get something together and, if anything, its proved to be a great learning experience.
 
hgher said:
Thanks for the response Alex. I've gone through and extracted the channels to separate mono files and as you've said ditched one of them for two copies of the other in a make-shift stereo file. It's not the idea solution and certainly not 'resolving' the issue (whoops), but it's the best I can do for now. I wasn't the sound recordist on the project so I'm not sure how everything was connected or which cables were used, but when we tested the initial recordings it played back OK on headphones. I'm hoping to salvage any sound I can get out of these files and so far it's going OK with the 'work-around' I've ended up adopting, I'm not 100% satisfied with it but my team abandoned the project before completion and I've had to pick up the pieces to get something together and, if anything, its proved to be a great learning experience.
Click to expand...
Out of phase channels will usually sound okay as stereo when listened in headphones because the two channels aren't interacting with each other that environment. But when mixed together, such as when they are mixed into mono or into a 5.1 centre channel they will cancel each other out. When played in a 5.1 setup, odd things can happen such as the front channels suddently flipping over into the rear. When played on regular stereo speakers the two channels interact in the air between the speakers and the listener with all sorts of comb filtering effects and partial canellations. In-phase stereo will sound well-localized between the speakers while out of phase stereo will sound vague and diffuse, appearing to come from space to the outside of the speakers.
 
hgher said:
I've gone through and extracted the channels to separate mono files and as you've said ditched one of them for two copies of the other in a make-shift stereo file. It's not the idea solution and certainly not 'resolving' the issue (whoops), but it's the best I can do for now.
Click to expand...

Making a copy of a mono channel and duplicating it to create a "stereo" source can easily introduce phasing issues. Not sure which program you're using, but most DAWs and audio editors will allow you to take a mono file and either pan it to center or export it as a stereo file without having to duplicate and paste. Either of those methods will solve your problem, but the copy and paste method can create as many problems as you're trying to solve.

Besides... this is a mono audio source anyway. Why do you need a stereo file? Once you put it into an NLE or a DAW to use it in a mix, you can simply use the "pan" feature in the audio clip controls to center it.

hgher said:
I wasn't the sound recordist on the project so I'm not sure how everything was connected or which cables were used, but when we tested the initial recordings it played back OK on headphones.
Click to expand...

Phasing is very easy to detect in headphones. As Steve said, it won't cancel itself out as it will on stereo or 5.1 playback systems, but when you listen through headphones you can "feel" it. Because the two channels (left and right) are fighting with each other, it both sounds and feels like the sound is being sucked into the center of your head.
 
dre83 said:
one mic = mono most of the times.

stereo = 2 mics or stereomic
Click to expand...
or a mixer with L and R out........ and then you can still only need one mic. 1 signal in from the mic........two out into L and R of the Zoom. Immediate control of the signal level.

Most dialogue tracks are input into the DAW as a mono track. Curious why you are doubling it for 5.1? If you are using a decent DAW, let the program send it where you want it. You should have a surround pan control for the output of that track. You may be having issues with the drivers/interface/DAW.......by using a stereo that is supposed to be L/R......the hardware/software may be working really hard to figure where you want to send a stereo (L/R) then re-outputting it into a 5.1 aspect (L, C, R, LB, RB, sub), and is cheating, in order to keep from crashing (taking an easier processing route).

You would definitely have phase issues if you took/created a stereo track from a single mono and tried to just force it into a 5.1 mix. Just use a single mono track, it will be way easier.



EDIT: LOL, I should learn to read ALL posts first before responding......Alex and Steve said this
 
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Alex H. said:
Making a copy of a mono channel and duplicating it to create a "stereo" source can easily introduce phasing issues. Not sure which program you're using, but most DAWs and audio editors will allow you to take a mono file and either pan it to center or export it as a stereo file without having to duplicate and paste. Either of those methods will solve your problem, but the copy and paste method can create as many problems as you're trying to solve.

Besides... this is a mono audio source anyway. Why do you need a stereo file? Once you put it into an NLE or a DAW to use it in a mix, you can simply use the "pan" feature in the audio clip controls to center it.
Click to expand...

For some reason the sound files were archived as stereo so I assumed they were recorded as such. After extracting to mono I've gone ahead and placed the files in media composer and applied the pan feature to center the audio and it's holding up OK. Thanks again for the advice, was pretty lost a week ago!
 
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