Mac and Ipad Internal Speaker playback problem

W

wayne atkins

New member
Any one with a solution to this please make contact wayne.atkins@xtra.co.nz but after 12 months we have found our clip http://www.youtube.com/watch?v=u3IE8o8cnWw plays back horribly when the interviews recorded with a sennheisser mkh 416 recorded onto a zoom n4h, and edited in avid media composer is played back on mac laptops or ipad internal speakers.

Connect a $5 set of earphones (!!!) to the mac laptop or ipad and sound restored.

What can we do to ensure playback on mac's and pc's will be the same, and audiable.
 
Wow. I didn't believe it, but it's true. Interviews disappeared on my iPod, but they are there when I watch on my Dell!?! I would try to talk to an Apple/Mac expert that knows the hardware and software, as well as web-programming. Are you a Mac owner? Do you have an Apple store nearby? If you can make an appointment at the "Genius Bar," you could at least get some advisement about whom to talk to... There seems to be some proprietary nonsense going on, which is strange because Mac's are known for their media-friendliness. Sorry I don't have an answer, but I can confirm that halfway across the world, it's still true: Mac=No Sound, Windows Machine=Sound.

GJ
 
Works on my MacBook Pro (10.6.8) and iPad 2. Interviews quieter than the music levels. Check your balance. If you have problems would suggest it's in the codec selected, settings for the codec and data rate. Since this is on youtube it's converted on their side but you can help that with what you upload.
 
Yeah it is the quiteness which is the problem, rather than just not being there at all.

My son is doing the edit with avid.

Could there be a setting there that he has missed
What I can not understand is that on PCs on ipads and macs with headphones it is OK?
 
It was messed up on my Macbook as well, except with headphones. It sounds like phase cancellation, but I cannot figure out how it would be okay in one place and not in another...

Just out of curiosity, what's his workflow? Is he taking two identical channels of audio ("stereo", even though it's mono dialog) and using them together? Is there a chance that one of them has slipped a bit?
 
we record using a sennhieser mhk 416 plugged into ONE of the two external LXR inputs on the zoom n4h and this is downloaded to the avid media composer which he edits on.

The sound recorded and edited from the zoom stereo mics is occassionally used in the final edit and when that happens, that sound plays ok.

Would the solution be to split the xlr cable from the mic and plug into both external input channels on the zoom, Does such a cable exist?
 
I did listen with earphones... as I said, it was a problem on my Macbook, except with headphones.

As for workflow, if you're using a single mic, and recording to a single channel, you shouldn't be experiencing phase cancellation... unless...

Depending on how your NLE system is set up, your H4n audio may be coming in as a stereo pair. The H4n is recording two channels, even though the mic is in only one, so you have a pair that includes the mic and a silent track. If your AVID system brings them in as a pair, they are defaulted to a stereo pan (1 to the left and 2 to the right). The proper way to deal with this is to split them, delete the empty track, and use the audio controls to pan the production channel to center. The improper way, whcih can cause phase cancellation, is to duplicate the production audio to a second track and pan it to the right to fill in. If the duplicate track isn't lined up correctly, if it gets shifted in the edit, it can cause issues.

Not saying this is what's happening here... but if that sounds familiar to the way this is being edited, please let us know.

I'll be back shortly... going to go play this back on a couple other computers and playback systems, just for giggles.
 
Just played it back on my Windows laptop and definitely get phase cancellation with the interviews. So somewhere along the line, the dialog is getting copied and knocked out of alignment.

I went back on both Mac and PC with better headphones and I can hear the phase problems in there as well. I used cheap ear buds the first time, and if one of the buds is slightly twisted off-axis it can tame the phasing effect... likely why it sounded fine to you and others who did the same thing. The phasing sounds slightly different in earphones/headphones than it does with speakers, but it's there.

It was even more audible in my edit suite, through my ProTools inteface and over Genelec monitors.

The reason you hear it (more) on your Mac's internal speaker, and your iPad's internal speaker, is because those are single speakers that play both channels back as a mono signal. That combines the out-of-phase channels and enhances the issue. If you listen with headphones, and pay attention, it sounds like the voices are coming from the center of your brain, rather than equally from both ears. The phasing issue means that the two channels are basically playing tug-o-war with the sound, which sucks it into an aural vortex in the middle.

Also, do I understand you correctly that you're sometimes using the audio from the internal, stereo mics along with the audio from the shotgun? This could possibly be part of the problem. However, as I listen more closely, it's evident that I'm hearing a single channel that has been knocked out of phase with itself.
 
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Yeah, I was going to say it sounds like a phase problem. Something is either happening in the NLE or on the export. Does it sound like that in the Avid? If not, what are your audio export settings?
 
You nailed it. I thought it was a weird stereo issue but didn't seem to be a stereo soundtrack. The left and right were different but the music seemed fine.
 
davefisk said:
Yeah, I was going to say it sounds like a phase problem. Something is either happening in the NLE or on the export. Does it sound like that in the Avid? If not, what are your audio export settings?
Click to expand...

It almost has to be in production/post. The music tracks are fine... just the dialog. Wonky export settings would fubar the whole thing, no?
 
Alex H. said:
It almost has to be in production/post. The music tracks are fine... just the dialog. Wonky export settings would fubar the whole thing, no?
Click to expand...

That's right. I've seen this happen when I've received tracks that were exported from FCP and the person didn't really know what they were doing. It's a mistake that happens, and we all learned from it.
 
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