View Full Version : Is it common for the HD feed to be 5 seconds behind the SD Feed?
RobertSeattle
10-22-07, 12:31 PM
Was watching our local Fox HD feed from DirectTV on the HR20 in the living room, and my wife turns on the SD TV in the Kitchen that uses a HR10 SD Fox Feed - she was watching "ahead" of me by about 5 seconds - very annoying - especially when watching sports! Same channel, the only difference was SD -vs- HD.
Is this common and I just never noticed it before?
say-what
10-22-07, 12:35 PM
They're 2 different feeds so it's quite posisble, and common, that there are different delays. Also, it's not uncommon for the HR20's signal to be delayed in comparison to the same signal on other boxes, so you get an echo effect if you have 2 HD boxes on the same channel or tune the same SD channel on another box.
Earl Bonovich
10-22-07, 12:37 PM
Yes...
In order of "time"
-) Live Event
-) AM/FM Radio broadcasts
-) Analog OTA
-) Digital OTA
-) Cable
-) SAT SD
-) SAT HD
Here is why:
It is a cumlative affect.........
The SD signal on HR10, via SAT...
Goes from the broadcast station, to DirecTV usually via a fiber connection or OTA... and then is sent up to DirecTV...down to their link center... then back up... and down to you.
The HD signal from a provider, is usually already behind the SD signal at the source... but then goes to DirecTV via OTA, which DirecTV has to decode, then re-encode... the up and down... and up and down....
So yes... 5 seconds is very normal.
Then if you are on a DVR... a just a little bit more for the delay in the buffers and things like that.
Was watching our local Fox HD feed from DirectTV on the HR20 in the living room, and my wife turns on the SD TV in the Kitchen that uses a HR10 SD Fox Feed - she was watching "ahead" of me by about 5 seconds - very annoying - especially when watching sports! Same channel, the only difference was SD -vs- HD.
Is this common and I just never noticed it before?
I've never experienced a 5 second difference before, but yeah, it's common for a few reasons. Different satellites are going to be farther away, adding a few milliseconds. A non DVR is going to process faster than a DVR, and 2 DVR's may process the signal differently, adding to the time delay. My HR10-250 is about 1/2 a second ahead of my HR20-700.
Come to think of it, are you sure the HR20 hadn't been paused for a couple of seconds?
RobertSeattle
10-22-07, 01:57 PM
I was getting annoyed by her going "Wow what a play"... while I was waiting for the hike... I made sure I was as up to the moment as possible, even changed the channel and back just to make sure something hadn't slipped with the buffer.
Maybe a 1 second difference would be OK, but this was definitely in the 5 second range. The speed of light is 186,000 miles per second so I have a hard time thinking it is cable/satelite travel time there, but maybe all the signal processing and unprocessing actually doesn't create a time hit.
mhayes70
10-22-07, 02:00 PM
Here is the St. Louis area I was watching the Blues on local CW11 Saturday night. It's SD feed on the satellite was 10 seconds behind the OTA feed. That is the biggest difference I have ever seen. It is usually around 5 seconds.
The speed of light is 186,000 miles per second so I have a hard time thinking it is cable/satelite travel time there...
yeah, I thought again about that after I posted, just didn't feel like editing the post. It's the hard drive buffering and video processing that does it. I'm sure the satellite has to process it, as well, slowing it down even more.
Earl Bonovich
10-23-07, 12:21 PM
Everyone of the little hops add's delays...
Including all the delays added, during all the encoding/decoding/encoding steps along the way.
3-5 seconds, is pretty normal
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tonyd79
10-23-07, 01:35 PM
When dealing with a local TV station, anything can happen. I have actually seen the HD OTA be ahead of the SD OTA. It is rare but it happens.
P Smith
10-23-07, 02:45 PM
There is some sort of quarantine time for broadcasters - remember Janet's malfunctioned wardrobe ?
Everyone of the little hops add's delays...
Including all the delays added, during all the encoding/decoding/encoding steps along the way.
3-5 seconds, is pretty normal
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So why is my HR 10-250 on CBS ch 80 HD always ahead of my Hr 20-700 on CBS ch 2 HD ??:(
randyk47
10-23-07, 03:07 PM
Quarantine delay would be added to the front of all feeds so OTA, sat, etc., would all be the same. Now I've not noticed SD - HD differences but certainly OTA - sat differences of a couple or more seconds. Wife will sometimes turn on the family room TV while I'm upstairs in the theater. If we just happen to be watching the same show hers will be ahead of mine as she likes OTA PQ on the Sony HD CRT downstairs.
I thought FM was faster than AM...it's LOS...AM isn't. :)
ExCavTanker
10-23-07, 03:20 PM
When I 'm talking with a friend of mine from Maine while watching the same football game I have checked with a stopwatch and he is an avg of 6.5 seconds ahead of me (SD cable for him, HD D* for me), that is huge! While certainly not life altering, it sure is frustrating when he knows the outcome of the play WAY before I do and has to try to keep quiet until the play is over on my end :D .
Earl Bonovich
10-23-07, 03:53 PM
When I 'm talking with a friend of mine from Maine while watching the same football game I have checked with a stopwatch and he is an avg of 6.5 seconds ahead of me (SD cable for him, HD D* for me), that is huge! While certainly not life altering, it sure is frustrating when he knows the outcome of the play WAY before I do and has to try to keep quiet until the play is over on my end :D .
Just don't make any quick bets...
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