View Full Version : 4 channels of audio.


Thomas Smet
September 14th, 2005, 06:06 PM
I loved the 4 channel audio recording on my XL1 and at first I was very excited to read about the XH1 having 4 audio channels. Does the XH1 really record 4 audio channels on HDV or is that for DV only recording? Where would they fit the other 2 channels for 1080i HDV since it already uses the full 25mbits? Perhaps the bitrates for the audio channels are cut in half to 192 kbits.

Chris Hurd
September 14th, 2005, 07:07 PM
Hi Thomas,

The official HDV spec has now changed with the introduction of the XL H1. The 24F, 25F and 30F frame rates are indeed supported by HDV, as is the four-channel audio feature.

You are correct about the bit rate... Four channels of 16-bit audio at 192kbps. The audio quality at that bit rate will have to be an individual judgement call based on the shooting situation.

Thomas Smet
September 15th, 2005, 01:01 AM
Thanks Chris for the info. I wouldn't think 192 kbits would be all that bad considering most of us are happy with 128 kbits mp3 files or 192 stereo dolby ac3 files. I know dolby is better than mpeg audio but I wouldn't think 192 kbits audio would be as bad as 32 khz audio with 4 channel DV. Don't most PAL DVD's as well as some NTSC DVD's already use 192 kbit stereo mpeg audio?

Daniel Kohl
September 15th, 2005, 03:18 AM
But for the audio to sound as good as mp3 or DVD audio, wouldn't have to be compressed while recording using one of those compressions at that bit rate?