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smudger_smith
10-06-2010, 02:00 PM
Hi

This is a similar problem to a couple of others on his forum. I connect my Foxsat-HDR to my TV via the HDMI socket. When watching any SD channel the volume setting on the TV is about 12 for comfortable listening. When I'm viewing either BBC HD or ITV HD I have to advance the volume level to 30 or more for the same listening level. If I forget to wind the volume down again before swapping back to an SD channel I can rattle the windows and my ear-drums! Anyone any idea why this is? I've looked in vain for some sub-menu item allowing me to pre-set the HD audio but in vain.

Cheers

Smudger
FenderBender
10-06-2010, 04:46 PM
I think this is a 'feature'of HD. They have to squeeze the transmission to get all the extra data that HD requires. A trade-off is to reduce volume which subsequently reduces the data rate.

You may notice ordinary DVDs have the same issue.
jim9200
10-06-2010, 04:47 PM
HD satellite channels sometimes broadcast audio in multi-channel format (AC3), with a much wider dynamic range than SD MPEG.

Some amplifiers have an option to adjust dynamic range compression, while some TVs have automatic volume adjustment.

There may be an alternate audio stream on BBC HD that uses MPEG encoding at "SD levels", but it often carries the audio description as well.
smudger_smith
11-06-2010, 08:13 AM
Hi

Thanks to you both for the responses. I had a feeling this might be a feature of HD and/or available bandwidth.

My TV (LG) has an automatic volume feature but it is just about unusable. The time constant for build up is far too short so that even slight pauses allow the volume to build up to unpleasant levels. When a sound occurs the level reduces abruptly giving me the impression of watching a home video made on a cheap camcorder. The intention is good with different time constants for build up and fade but the implementation is poor and the preset levels are too spread - at least for my liking.

So it looks like I'll have to live with this and learn to reduce the volume before leaving an HD channel.

Thanks again.

Smudge