16 or 24 bit audio for my camera?

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offbeatbryce

Well-known member
How do I tell what bit rate of audio my canon xa20 films at? If I plugin an XLR line in from a mixing board what's the bit rate in audio? Premiere just tells me in properties it's 48 khz compressed. Doesn't list the bit rate at all.

My canon camera manual isn't much help either.

Screen shot of audio formats from manual: http://i.imgur.com/ezQuNV4.png
 
Jim Feeley said:
I was going to guess 16-bit, since Canon was in general late to the 24-bit audio game. So I googled up the specs, and sure enough:
https://www.usa.canon.com/internet/portal/us/home/products/details/camcorders/professional/xa20/

Linear PCM (2ch)* / Dolby Digital (5.1ch when SM-V1 is used) * Feature supported only in the 28 Mbps/23.98 Mbps recording mode; resolution: 16 bits
Click to expand...

Is 16 bit bad? I know that's used for CD but if that's all I have then I have to work with it. the footage is of a concert and I had the line in from the soundboard into xlr on my camera so it's 16 bit. It's just going on YouTube.

What happens if I had recorded into a digital audio recorder at 24 bit? Would it be true 24 bit or does it also depend on the mixing board used?
 
offbeatbryce said:
How do I tell what bit rate of audio my canon xa20 films at? If I plugin an XLR line in from a mixing board what's the bit rate in audio? Premiere just tells me in properties it's 48 khz compressed. Doesn't list the bit rate at all.
Click to expand...

Plugging in from a sound board via XLR has no impact on bit depth. The audio flowing down that XLR cable is analog and is not dependent on sample rate or bit depth. Those are specs that relate only to digital audio, and the bit-depth of the recorded audio in the camera is completely dictated by the camera's setup.

Digital video runs at a native 48kHz sample rate and a native 16-bit depth. Most all dedicated sound recorders can record at the higher 24-bit depth, and very few cameras out there do. 16-bit is perfectly acceptable, but lower record levels can result in artifacts in post especially if adding audio filters and plug-ins. 24-bit audio, when available, gives a little more data to work with in post.

Since your footage is showing as compressed audio, I assume you're recording in MP4 instead of AVCHD. Compressed digital audio (usually AAC) has different specs than uncompressed digital audio, but you're probably safe to assume that, within Premiere, you're working with 16-bit audio.
 
How do I tell what bit rate of audio my canon xa20 films at?
You seem to be confusing RATE with DEPTH (or width).
The standard RATE for audio for video is 48KHz You can assume 48KHz sampling rate for all video unless it says otherwise.
Virtually all camcorders record at a bit DEPTH of 16-bits.

If I plugin an XLR line in from a mixing board what's the bit rate in audio?
It has nothing to do with the source of the audio.
It has everything to do with what the recorder (or camcorder, etc.) is configured for.

Premiere just tells me in properties it's 48 khz compressed. Doesn't list the bit rate at all.
48KHz is the sample rate. The "bit rate" depends on the data compression factor.

Is 16 bit bad?
It's just going on YouTube.
By the time it is sentout from YouTube, it probably isn't even the equivalent of 16-bit.

...I had the line in from the soundboard into xlr on my camera so it's 16 bit.
It is whatever the recorder/camcorder is set for. It has nothing to do with the equipment source or the program material.

What happens if I had recorded into a digital audio recorder at 24 bit?
Would it be true 24 bit or does it also depend on the mixing board used?
Yes, it would be true 24 bit. Again, it has nothing to do with the equipment source or the program material.

Given the option, many of us prefer to use 24 bit recording for live musical events because it gives a better "safety-margin" before the signal starts to clip. Even if you get a proper sound-check before the program to set levels, you can almost depend on the peaks for a live performance going 3dB or even 6dB higher than what you encountered in the rehearsal. And, of course if you got no rehearsal, then you will have to use your judgement about recording levels. Whatever you are recording with (a proper sound recorder or directly to your camcorder.)
 
If Premiere is telling you that it is compressed, you might not have your camera set to linear pcm. Make sure that you are recording with LPCM as part of the bit rate/ frame rate setting. Otherwise, you are really limiting yourself with internal audio.
 
cpreston said:
If Premiere is telling you that it is compressed, you might not have your camera set to linear pcm. Make sure that you are recording with LPCM as part of the bit rate/ frame rate setting. Otherwise, you are really limiting yourself with internal audio.
Click to expand...

With the XA20, if shooting in MP4 the only audio recording option is AAC (compressed). Switching to AVCHD opens up the options of Linear PCM (uncompressed).
 
More to the point is what is the quality like coming from the mixing desk?
Or are they playing out MP3's or even worse tracks from compact cassettes?...... yes there are some productions that still do.
 
Richard said "Virtually all camcorders record at a bit DEPTH of 16-bits.)

Times they are a changing. Some cams are now recording in 24bit. My Panasonic does.

Best Regtards, Grant

Edit: I surely hate the spelling auto correct feature.....makes me look like an idiot unless I proof read.......
 
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