View Full Version : Does HD250 record 4 tracks of Audio?


Jack Walker
November 19th, 2006, 04:19 PM
In the past it has been talked about that the HD100 would record wav audio as well as compressed audio. However, it appeared from people's tests and reports that this was not true, though I have never seen an official statement regarding this from JVC.

Do the HD100 and HD110 record 4 tracks or not in the final analysis.

Is there any difference between the HD110 and the HD250 in this regard?

Thanks!

Carl Hicks
November 19th, 2006, 05:44 PM
In the past it has been talked about that the HD100 would record wav audio as well as compressed audio. However, it appeared from people's tests and reports that this was not true, though I have never seen an official statement regarding this from JVC.

Do the HD100 and HD110 record 4 tracks or not in the final analysis.

Is there any difference between the HD110 and the HD250 in this regard?

Thanks!

Hi Jack,

No ProHD camera to date can do 4 channel audio.

Regards,

Ken Hodson
November 19th, 2006, 06:00 PM
I remember from the early days of HDV it was stated that the 720p format was limited to 19.7 Mb/s as to reserve space for future audio. Why has this not come to light yet? And if there was never any intention of this why has the 720p HDV format left those 5.3Mb/s sitting there unused and useless? I completely expected the new 200/250's to use this space for PCM audio and if not for sure use it for video being they were trying to squeeze 60p in the older cams 30p space. Thats a %25 of tape bandwidth sitting unused. Why?
Can we imagine the new "super-encoder" using the full bandwidth like the 1080i variants. Ouch!

Carl Hicks
November 19th, 2006, 06:21 PM
I remember from the early days of HDV it was stated that the 720p format was limited to 19.7 Mb/s as to reserve space for future audio. Why has this not come to light yet? And if there was never any intention of this why has the 720p HDV format left those 5.3Mb/s sitting there unused and useless? I completely expected the new 200/250's to use this space for PCM audio and if not for sure use it for video being they were trying to squeeze 60p in the older cams 30p space. Thats a %25 of tape bandwidth sitting unused. Why?

Hi Ken,

All in good time. The GYHD200 and 250 bring a huge amount of new features to the market, most of them by request from end users. The fact that these two new cameras have come to market a little over a year after the GYHD100 shipped is a testament to our desire to fulfill customer requests as technology allows. The ProHD family will evolve over the years and bring more and more features market. Patience please.

The choice of 19.7 Mb/Sec bandwidth for HDV1, from what I know, was chosen not only to allow some headroom for other information, but also to be compatible with broadcast DTV channels, which use the same bandwidth. Plus, the HDV1 signal can be fed down a SD digital microwave, thus allowing broadcasters to do things like a HD live shot send by a SD microwave system. In fact, this is starting to be done now by a few broadcasters. This would not be possible if our bandwidth went any higher.

In fact, some of our broadcast customers were the ones who pushed for the development of the 50p and 60p, but they specifically said to "do this without increasing the bandwidth." Our engineers found a way to do it.

Steve Benner
November 19th, 2006, 07:01 PM
Hi Ken,
The ProHD family will evolve over the years and bring more and more features market.


That's some very cool news as I am glad to here the company is looking foward. I love my HD100 and it is the best in it's class.

For the record though, if you want to send some feedback to the company, I think that ProHD should move towards Native 1080P, Blue Layer Disk Recording and Variable Frame Rates with Uncomressed Audio.

Brian Duke
November 19th, 2006, 08:30 PM
I record to separate audio so I have access to 4-7 tracks of audio. However, I still record to camera, but I rarely, if ever use it.