Exported Sound as AIFF from FCP has noise

Hi,

A sound designer is going to tweak the some of the audio for my trailer that I am editing in FCP 5.0. with OS X 10.4.11 He needs a CD of the sound to import it into his old Fairlight System ( it does not firewire, hence the reason for the CD).

I exported the audio from the sequence, Using QT conversion (to AIFF) and Export Audio to AIFF. Then, in Toast 6.0.5 I burned a CD. When the CD was finished it was renamed Witchcraft (because I had previously burned a CD when I downloaded the song from itoons to use as temp music in my film). It also had loud static noise in with the audio. I've never done this before, but even so, it seems my computer is possessed. Any suggestions?

Colleen

A couple of things:

1. Did you do an Audio Mixdown?

2. If it's a sound designer, why not export an OMF? You can do AIFFs, but then you'd have to do each track individually, and you'd have to manually remove all levels, filters and transitions from your timeline or they'll be a permanent part of the sound.

3. Burning to audio CD is not the way to go. The audio in your timeline is 48kHz and audio CDs are 44.1kHz, but your final mix should be at least 48kHz. You're losing a generation for no reason. Just export the files and burn them to a data disc (CD/DVD), or use a USB flash drive, or use an external FireWire drive. Give your designer maximum-quality files, not an audio CD.


www.derekmok.com

Quote
http://en.wikipedia.org/wiki/Audio_Interchange_File_Format
Apple uses this new little-endian AIFF type as its standard on Mac OS X. When a file is imported to or exported from iTunes in "AIFF" format, it is actually AIFF-C/sowt that is being used. When audio from an audio CD disc is imported by dragging to the Mac OS X Desktop, the resulting file is also an AIFF-C/sowt. In all cases, Apple refers to the files simply as "AIFF", and uses the ".aiff" extension.

For the vast majority of users this technical situation is completely unnoticeable and irrelevant. The sound quality of standard AIFF and AIFF-C/sowt are identical, and the data can be converted back and forth without loss. Users of older audio applications, however, may find that an AIFF-C/sowt file will not play, or will prompt the user to convert the format on opening, or will play as static.

That was from wikipedia... I haven't encountered this before (or maybe i have a long while ago). I believe static (white noise) may also occur when the information gets scrambled.

But in any case,

1) If you are working in 48khz (which is typical of video), do not burn a CD, as you're down sampling the audio to 44.1 khz 16 bits. Instead, export it as 48 khz as your sequence setting (24 bits if he can handle it), and burn a data cd with the aiff files on it. If he's working on a PC with an older software, you could encode it to big endian.

2) If your audio contains separate music tracks, you should be sending him an OMF file with a low resolution video for reference instead.



www.strypesinpost.com

Wow. And Derek beats me to the post again! Maybe you're situated closer...



www.strypesinpost.com

Hi Gerald and Derek,

I sent your responses to my friend who is doing sound. He said he needs a "regular audio CD" so that he can import the sound into his Fairlight System - which has no firewire. He's only tweaking the a five clips of audio. I'm in my documentary and my voice is too soft in some places and too loud in others. He wasn't trilled with the FCP options, so he wants to import it into his system which is older but very high end. Plus, he doesn't know FCP. Anyway, I'll get back to you when he responds. Thanks for you help!!!

Hi Gerald and Derek,

I just spoke to my sound designer friend and he wants me to make a DVD of the audio. Thanks so much for all your help!

Colleen

>He wasn't trilled with the FCP options

Agreed. I'm not thrilled with the FCP options for audio mixing myself. It's really pants. Soundtrack Pro is where I go for final mixes/mastering. Haven't touched Logic or Pro Tools lately, but they're more powerful..

Just checked up Fairlight. It's a Console? Nvm. Thought it was a DAW..

> he wants me to make a DVD of the audio.

Then you should use the AIFF option for the DVD, don't have to select "best quality" as he is not likely going to need great picture quality, but he needs good sound.

Alternatively, if you would need a CD, you could try sending it to Soundtrack Pro and doing the conversion there (down sample it to AIFF 44.1/16 bits before sending it to iTunes, select "dithering" on export)



www.strypesinpost.com

> he wants me to make a DVD of the audio.

Video DVD for audio delivery? The files we use to make video DVDs with can be close to the original in quality, but I'm honestly not sure what happens when you encode and then he has to rip it back out for the mix. I've never heard of a video DVD on any sound deliverable. Also, you still have the problem that all your audio will be mixed together. What your friend is asking for just doesn't make sense to me. Can anybody vouch for this kind of workflow?


www.derekmok.com

Given the circumstances, it seems alright to me, in fact, a better format than CD. Audio can be stored as linear PCM; 48khz; 16 or 24 bits (naturally, higher the better). Mux into DVD assets, demux it on the other end, it's lossless..

Naturally, he won't want it flattened, the audio can be spread out, after the video, with good long video black on top, with 2-pops to knock the audio tracks in sync.

It's a matter of the decoding and the signal flow. I've never heard of AES/EBU outputs from DVD players though... Not sure if it exists for CDs either.

Fairlight seems more like a recording/mixing console that you may have synced up to an open reel or a hard disk recorder device. Any info on this set up?

The workflow certainly isn't very conventional (it's commonly ProTools and OMFs), but DVDs beats downsampling to 44.1khz, flattened, then upsampling it back to 48khz to sync it back for video delivery. DATs are more frequently used for audio transfers, as you go in and out via AES/EBU...

For DVDs, you don't compress it to dolby digital (.ac3) for this...

Anyone?



www.strypesinpost.com

I presume he's asking for a data DVD with relevant files on it, not a playable DVD which would mean AC3 encoding all audio, which would then have to be de-muxed...

I actually HAVE a CD player with AES out, a high end Denon unit meant for broadcast use. GPI's for triggering, 9 pin control. Awesome sound as far as 16 bit goes.

Fairlights are old science but they're pretty cool. Heavy iron. Really mini-computers (in the old terminology), a la DEC, as opposed to general-purpose Macs or PCs. Nothing more than a standard DAW, but very complex if you've never used one and great sound due to the D/A converters. The old systems were primarily editorial systems, but you could mix on them if you really tried. Mostly, though, you'd find them on large mix stages feeding large mixing consoles. They also crashed a lot, as I recall.

The few guys left who can fly them can really fly fast. Great for dialog cutting. I never liked mixing on the older systems. Later in life they focused on mixing surfaces, but I've never mixed on one of those. As I recall, mixing on the older systems was really a matter of changing clip levels, but I'm sure there was more to it than that. I was cutting dialog at the time (10 years ago) so clip level was all that was required. The great thing about Fairlights was that they could sync to SMPTE timecode in reverse - something impossible even today with most DAW systems - which was a holdover from the way re-recording mixers had worked for decades (I'd be happy to go into why this used to be important for anyone who's interested, but I won't bore you with it here, now).

File management on Fairlights - including OMF extraction, etc - is almost a command line exercise, at least it was on the system I was using. No drag & drop. PITA.

forgot to address the problem. In my experience, noise bursts are due to problematic disks. Seems to happen a lot with SCSI disks. Or an otherwise corrupt file.

Reid C

Thanks for the word, Reid. Wow. Never touched a Fairlight.

In my opinion, D/A converters (and the error correction) are EVERYTHING to audio- they can make 44.1/16 sound even better than some 96/24 devices.

>I presume he's asking for a data DVD with relevant files on it, not a playable DVD which
>woule me AC3 encoding all audio,

I'd think he really meant DVD video (or audio, but that would require a completely different encoder out of FCS), as he didn't seem to like the data cd. DVD video specs for audio allow for dts, pcm, ac3, and mpeg2 audio. But it would have to be encoded as aiff and demuxed if the transfer is to be lossless (i really doubt a DVD player with AES/EBU outputs exist, or even SDIs). Strangely, I can't seem to get the official paper, but I thought 96khz could only be used in DVD-Audio. Ahh...

Here's an article on it- 24/96 up to 2 channels for DVD video (pg 56-57); for DVD-A, Super high-quality linear PCM audio ? 192/176.4kHz and 16/20/24 bits, two channels maximum (pg 57).

[www.ambisonic.net]

What's interesting too, is that Sony and Phillips (the inventors of the audio CD format) eventually lost the war on SACDs.

>I actually HAVE a CD player with AES out, a high end Denon unit meant for broadcast use.

I vaguely remember using CD burner decks with AES ins.



www.strypesinpost.com