mixing 24 bit and 16 bit audio in timeline (both at 48khz)

[Bouncing Account needs new email address]

You can’t set the card to 16 bit/48kHz ?

[Khashyar Darvich]

Hi Matte,

Thanks for your response.

It seems as though I cannot change the BetaSp-DV conversion setting on the Kona LHe that will change the fact the audio is converted to 24 bit audio (at 48khz) instead of 16 bit (at 48 khz).

There is an easy setup setting in FCP whereby I can choose “8 bit to DV” conversion, but after I captured the footage, the audio is 24 bit/48khz…

I tried to combine 24 bit and 16 bit audio in the same timeline, and it seems to play fine. But, I don’t know how this will affect mastering, etc…. I guess I have to pay attention to audio pops and other audio issues…

But, I’ve rented a BetaSP deck for the weekend, and I want to make sure that the BetaSP audio that I capture is going to work, so I don’t have to rent the deck again.

Khashyar

[Khashyar Darvich]

Well, I found out that the sequence that I created when I was first capturing my DV footage has an “Audio Format” of “32-bit floating point” and a 48khz “Audio Rate.”

So, it seems that the “Audio format,” whether it is 16 bit, 24 bit, or another bit rate is far less important than having the audio at the same 48khz Audio Rate.

I would appreciate if someone could confirm this for me.

Thank you,

Khashyar

[Khashyar Darvich]

I spoke with a sound engineer friend of mine (who has worked extensively with Pro Tools, as well as has done sound mixes for film on FCP), and he told me that the Audio Rate (48 khz) was the important thing to keep consistent, and that he believes that it does not matter if you mix different bit rates of audio, as long as the Audio Rate was the same.

I wanted to pass that along if anyone else had a question about this.

Khashyar

[Meesta Joe]

This is correct. Mixing bit lengths (24-bit with 16-bit) is not a problem. Mixing Sample frequencies is less desireable. I’m not sure if the FCP timeline can combine 16 & 24 bit, but you can easily convert the 24 bit files to 16 bit. There are many programs that will do this in batch. Download a trial version of Sound Grinder. It does a great job at converting Audio files of many formats.

AG

[Khashyar Darvich]

Thanks for your feedback, AG.

If I find that I need to, I will use one of the converter programs that you mentioned.

Actually, I tried to place the 24 bit and 16 bit audio tracks in the same timeline, and they seem to co-exist fine together. I will post information here if I find that it is becoming an issue. (I welcome anyone else to post if they have experienced probnlems mixing 24 and 16 bit audio.

Khashyar

[John Pale]

If you are mixing your audio in Pro Tools you might want to do some tests. There are some older versions that will not deal with an OMF file that has mixed bit rates.

[Khashyar Darvich]

Thanks, John.

I am having a sound engineer friend of mine mix the film in Pro Tools after the online is finished. I think he has a pretty new version of Pro Tools.

Khashyar

[Meesta Joe]

FYI, there are no versions of Pro Tools that allow you to mix bit rates. Everything needs to be converted to 16 or 24 bits beforehand.

[John Pale]

good to know. I knew it was a problem on older systems, but was not sure if they fixed that. It used to be that you could not mix bit rates on an Avid, but they have overcome that issue.