Question for Sylvia: Splitting AV output

[DavidW]

Dear Sylvia,

Let's say I have a video device that has an AV output (3-socket RCA, for video,
L & R). Can I connect it to the AV inputs of two other video devices (say a TV
and something else) without loss of quality or blowing anything up? The
connection would be done by having effectively two AV cables (with 3 plugs each)
in parallel connected to said AV output.

 

[DavidW]

Brad wrote:

On May 10, 9:51 am, "DavidW" <n...@email.provided> wrote:
Dear Sylvia,

Let's say I have a video device that has an AV output (3-socket RCA,
for video, L & R). Can I connect it to the AV inputs of two other
video devices (say a TV and something else) without loss of quality
or blowing anything up? The connection would be done by having
effectively two AV cables (with 3 plugs each) in parallel connected
to said AV output.

Can I chip in here?

Certainly.

Yes it will work, but perhaps not perfectly. It will depend on the
performance of the equipment. The Video portion of the AV signal is
1Vp-p across 75 ohms. Put two devices on that and you will see 0.5Vp-p
across 37 ohms. The weaker signal may cause sync problems (less likely
with modern equipment) and poorer brightness. The audio may similarly
be lower, but you can turn the volume up to compensate. AV switch
boxes are available cheaply, to prevent these signal losses.

Thanks. I thought it was probably a bit dodgy. I assume that a switch box (would
splitter be a better description?) would require its own power supply, with
transformer. I was hoping to avoid that.

 

[Sylvia Else]

On 10/05/2013 9:51 AM, DavidW wrote:

Dear Sylvia,

Let's say I have a video device that has an AV output (3-socket RCA, for video,
L & R). Can I connect it to the AV inputs of two other video devices (say a TV
and something else) without loss of quality or blowing anything up? The
connection would be done by having effectively two AV cables (with 3 plugs each)
in parallel connected to said AV output.

Brad has summerised the issues, and I agree with him, except as far as
the audio is concerned. In my experience, audio inputs have a relatively
high impedance, and I would not expect the same problem.

Beware of creating ground loops.

Sylvia.

 

[DavidW]

Sylvia Else wrote:

On 10/05/2013 9:51 AM, DavidW wrote:
Dear Sylvia,

Let's say I have a video device that has an AV output (3-socket RCA,
for video, L & R). Can I connect it to the AV inputs of two other
video devices (say a TV and something else) without loss of quality
or blowing anything up? The connection would be done by having
effectively two AV cables (with 3 plugs each) in parallel connected
to said AV output.

Brad has summerised the issues, and I agree with him, except as far as
the audio is concerned. In my experience, audio inputs have a
relatively high impedance, and I would not expect the same problem.

Beware of creating ground loops.

Probably better to ditch it altogether. For example, I don't want to have to
adjust brightness between the split source and other sources. It all sounds too
dodgy.

 

[Brad]

On May 10, 9:51 am, "DavidW" <n...@email.provided> wrote:

Dear Sylvia,

Let's say I have a video device that has an AV output (3-socket RCA, for video,
L & R). Can I connect it to the AV inputs of two other video devices (say a TV
and something else) without loss of quality or blowing anything up? The
connection would be done by having effectively two AV cables (with 3 plugs each)
in parallel connected to said AV output.

Can I chip in here?
Yes it will work, but perhaps not perfectly. It will depend on the
performance of the equipment. The Video portion of the AV signal is
1Vp-p across 75 ohms. Put two devices on that and you will see 0.5Vp-p
across 37 ohms. The weaker signal may cause sync problems (less likely
with modern equipment) and poorer brightness. The audio may similarly
be lower, but you can turn the volume up to compensate. AV switch
boxes are available cheaply, to prevent these signal losses.

 

[DavidW]

Brad wrote:

On May 10, 10:13 am, "DavidW" <n...@email.provided> wrote:
Brad wrote:
AV switch boxes are available cheaply, to prevent these
signal losses.

Thanks. I thought it was probably a bit dodgy. I assume that a
switch box (would splitter be a better description?) would require
its own power supply, with transformer. I was hoping to avoid that.

A switch box and a splitter are not the same thing. A switch box
selects a different input or output, one at a time. A passive splitter
will reduce the output. An active splitter contains an amplifier, so
full output, but requires a power source.

I misunderstood then. I thought you were suggesting a "switch" that would solve
the signal-loss problem while maintaining the two simultaneous connections. A
passive switch was my first thought and what I'll probably go with, but parallel
connections would be better for my purpose so I thought I'd ask.

 

[Peter Bowditch]

Brad <bradvk2qq@gmail.com> wrote:

On May 10, 10:13 am, "DavidW" <n...@email.provided> wrote:
Brad wrote:
On May 10, 9:51 am, "DavidW" <n...@email.provided> wrote:
Dear Sylvia,

Let's say I have a video device that has an AV output (3-socket RCA,
for video, L & R). Can I connect it to the AV inputs of two other
video devices (say a TV and something else) without loss of quality
or blowing anything up? The connection would be done by having
effectively two AV cables (with 3 plugs each) in parallel connected
to said AV output.

Can I chip in here?

Certainly.

Yes it will work, but perhaps not perfectly. It will depend on the
performance of the equipment. The Video portion of the AV signal is
1Vp-p across 75 ohms. Put two devices on that and you will see 0.5Vp-p
across 37 ohms. The weaker signal may cause sync problems (less likely
with modern equipment) and poorer brightness. The audio may similarly
be lower, but you can turn the volume up to compensate. AV switch
boxes are available cheaply, to prevent these signal losses.

Thanks. I thought it was probably a bit dodgy. I assume that a switch box (would
splitter be a better description?) would require its own power supply, with
transformer. I was hoping to avoid that.

A switch box and a splitter are not the same thing. A switch box
selects a different input or output, one at a time. A passive splitter
will reduce the output. An active splitter contains an amplifier, so
full output, but requires a power source.

I bought a cheap plasticy switch on eBay so The World's Finest
Grandson can connect his Wii when he visits without having to climb
behind the furniture. Seems to work without any problems.

--
Peter Bowditch aa #2243
The Millenium Project http://www.ratbags.com/rsoles
Blog at http://peterbowditch.com/wp/
To email me use my first name only at ratbags.com
I'm @RatbagsDotCom on Twitter

 

[Brad]

On May 10, 10:13 am, "DavidW" <n...@email.provided> wrote:

Brad wrote:
On May 10, 9:51 am, "DavidW" <n...@email.provided> wrote:
Dear Sylvia,

Let's say I have a video device that has an AV output (3-socket RCA,
for video, L & R). Can I connect it to the AV inputs of two other
video devices (say a TV and something else) without loss of quality
or blowing anything up? The connection would be done by having
effectively two AV cables (with 3 plugs each) in parallel connected
to said AV output.

Can I chip in here?

Certainly.

Yes it will work, but perhaps not perfectly. It will depend on the
performance of the equipment. The Video portion of the AV signal is
1Vp-p across 75 ohms. Put two devices on that and you will see 0.5Vp-p
across 37 ohms. The weaker signal may cause sync problems (less likely
with modern equipment) and poorer brightness. The audio may similarly
be lower, but you can turn the volume up to compensate. AV switch
boxes are available cheaply, to prevent these signal losses.

Thanks. I thought it was probably a bit dodgy. I assume that a switch box (would
splitter be a better description?) would require its own power supply, with
transformer. I was hoping to avoid that.

A switch box and a splitter are not the same thing. A switch box
selects a different input or output, one at a time. A passive splitter
will reduce the output. An active splitter contains an amplifier, so
full output, but requires a power source.

 

[Bob Milutinovic]

"DavidW" <no@email.provided> wrote in message
news:kmhs29$tos$1@speranza.aioe.org...

Brad wrote:
On May 10, 10:13 am, "DavidW" <n...@email.provided> wrote:
Brad wrote:
AV switch boxes are available cheaply, to prevent these
signal losses.

Thanks. I thought it was probably a bit dodgy. I assume that a
switch box (would splitter be a better description?) would require
its own power supply, with transformer. I was hoping to avoid that.

A switch box and a splitter are not the same thing. A switch box
selects a different input or output, one at a time. A passive splitter
will reduce the output. An active splitter contains an amplifier, so
full output, but requires a power source.

I misunderstood then. I thought you were suggesting a "switch" that would
solve the signal-loss problem while maintaining the two simultaneous
connections. A passive switch was my first thought and what I'll probably
go with, but parallel connections would be better for my purpose so I
thought I'd ask.

As Brad and Sylvia have said, you'll have issues with the video signal - not
enough to prevent you from seeing it on both outputs, but more than enough
to drag the video quality into the mud (remember making copies of copies of
VHS tapes, and how good the resulting recording was?).

If you have $47 to spare, grab this; it'll do the job properly for both
audio and video, and has four outputs rather than just two;
http://www.ebay.com.au/itm/121073559070

If you want to save a bit of money and have a 12V power supply of reasonable
grunt laying around (1A output should suffice), this one does just the video
for $14; http://www.ebay.com.au/itm/261190349984

Audio isn't a problem unless you're wanting genuinely high fidelity (which I
suspect you're not); as Sylvia points out, most amplifiers have a
comparatively high input impedance (generally several tens of kiloohms or
higher), so there won't be any noticable signal degradation.

--
Bob Milutinovic
Cognicom

 

[Sylvia Else]

On 10/05/2013 8:47 PM, Coach wrote:

Very interesting topic. I have done exactly as the original poster has
done and not noticed any loss of quality.

Some equipment has an automatic gain control on the video input, which
would obviate most of the adverse effects. But it's not part of the
spec, so trying it in a particular instance is the only way to know
whether it'll work.

Sylvia.

 

[Coach]

On May 10, 6:45 pm, "Bob Milutinovic" <cogni...@gmail.com> wrote:

"DavidW" <n...@email.provided> wrote in message

news:kmhs29$tos$1@speranza.aioe.org...









Brad wrote:
On May 10, 10:13 am, "DavidW" <n...@email.provided> wrote:
Brad wrote:
AV switch boxes are available cheaply, to prevent these
signal losses.

Thanks. I thought it was probably a bit dodgy. I assume that a
switch box (would splitter be a better description?) would require
its own power supply, with transformer. I was hoping to avoid that.

A switch box and a splitter are not the same thing. A switch box
selects a different input or output, one at a time. A passive splitter
will reduce the output. An active splitter contains an amplifier, so
full output, but requires a power source.

I misunderstood then. I thought you were suggesting a "switch" that would
solve the signal-loss problem while maintaining the two simultaneous
connections. A passive switch was my first thought and what I'll probably
go with, but parallel connections would be better for my purpose so I
thought I'd ask.

As Brad and Sylvia have said, you'll have issues with the video signal - not
enough to prevent you from seeing it on both outputs, but more than enough
to drag the video quality into the mud (remember making copies of copies of
VHS tapes, and how good the resulting recording was?).

If you have $47 to spare, grab this; it'll do the job properly for both
audio and video, and has four outputs rather than just two;http://www.ebay.com.au/itm/121073559070

If you want to save a bit of money and have a 12V power supply of reasonable
grunt laying around (1A output should suffice), this one does just the video
for $14;http://www.ebay.com.au/itm/261190349984

Audio isn't a problem unless you're wanting genuinely high fidelity (which I
suspect you're not); as Sylvia points out, most amplifiers have a
comparatively high input impedance (generally several tens of kiloohms or
higher), so there won't be any noticable signal degradation.

Very interesting topic. I have done exactly as the original poster has
done and not noticed any loss of quality. But then again, I could
never see what people were going on about HD tv because I could never
really see the difference unless it was on a very large TV set. I
would have thought that high def tv would mean we'd buy smaller TV's
and sit closer to them, not buy bigger sets, Nobody seems to get
that.

 

[DavidW]

Bob Milutinovic wrote:

"DavidW" <no@email.provided> wrote in message

I misunderstood then. I thought you were suggesting a "switch" that
would solve the signal-loss problem while maintaining the two
simultaneous connections. A passive switch was my first thought and
what I'll probably go with, but parallel connections would be better
for my purpose so I thought I'd ask.

As Brad and Sylvia have said, you'll have issues with the video
signal - not enough to prevent you from seeing it on both outputs,
but more than enough to drag the video quality into the mud (remember
making copies of copies of VHS tapes, and how good the resulting
recording was?).

If you have $47 to spare, grab this; it'll do the job properly for
both audio and video, and has four outputs rather than just two;
http://www.ebay.com.au/itm/121073559070

If you want to save a bit of money and have a 12V power supply of
reasonable grunt laying around (1A output should suffice), this one
does just the video for $14; http://www.ebay.com.au/itm/261190349984

Audio isn't a problem unless you're wanting genuinely high fidelity
(which I suspect you're not); as Sylvia points out, most amplifiers
have a comparatively high input impedance (generally several tens of
kiloohms or higher), so there won't be any noticable signal
degradation.

As an audiophile I do want hi-fi sound on one of the inputs (I have the option
of directing its audio to a stereo amplifier and high-quality speakers for
those movies/shows that are worthwhile having hi-fi sound). One of the reasons
for my connection complications is that I prefer the convenience of the plain
TV sound to watch the news or Biggest Loser, but it's not good enough for
Raiders of the Lost Ark. (There are other issues too, such as whether I need a
source to go to recording equpment.)

Thanks for your suggestions. I hoped to avoid another powered device, but I'll
consider it along with a plain switch.

 

[Jasen Betts]

On 2013-05-09, DavidW <no@email.provided> wrote:

Dear Sylvia,

Let's say I have a video device that has an AV output (3-socket RCA, for video,
L & R). Can I connect it to the AV inputs of two other video devices (say a TV
and something else) without loss of quality or blowing anything up? The
connection would be done by having effectively two AV cables (with 3 plugs each)
in parallel connected to said AV output.

it's an analogue signal therefore there will be some loss of quality.
You won't blow anything up that wasn't already broken.

--
⚂⚃ 100% natural

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

 

[felix_unger]

On 11-May-2013 9:02 AM, DavidW wrote:

Bob Milutinovic wrote:
"DavidW" <no@email.provided> wrote in message
I misunderstood then. I thought you were suggesting a "switch" that
would solve the signal-loss problem while maintaining the two
simultaneous connections. A passive switch was my first thought and
what I'll probably go with, but parallel connections would be better
for my purpose so I thought I'd ask.
As Brad and Sylvia have said, you'll have issues with the video
signal - not enough to prevent you from seeing it on both outputs,
but more than enough to drag the video quality into the mud (remember
making copies of copies of VHS tapes, and how good the resulting
recording was?).

If you have $47 to spare, grab this; it'll do the job properly for
both audio and video, and has four outputs rather than just two;
http://www.ebay.com.au/itm/121073559070

If you want to save a bit of money and have a 12V power supply of
reasonable grunt laying around (1A output should suffice), this one
does just the video for $14; http://www.ebay.com.au/itm/261190349984

Audio isn't a problem unless you're wanting genuinely high fidelity
(which I suspect you're not); as Sylvia points out, most amplifiers
have a comparatively high input impedance (generally several tens of
kiloohms or higher), so there won't be any noticable signal
degradation.
As an audiophile I do want hi-fi sound on one of the inputs (I have the option
of directing its audio to a stereo amplifier and high-quality speakers for
those movies/shows that are worthwhile having hi-fi sound).

In that case you will need good quality audio leads. However no 'true'
audiophile would want anything less than digital audio I would suggest.

One of the reasons
for my connection complications is that I prefer the convenience of the plain
TV sound to watch the news or Biggest Loser, but it's not good enough for
Raiders of the Lost Ark. (There are other issues too, such as whether I need a
source to go to recording equpment.)

Thanks for your suggestions. I hoped to avoid another powered device, but I'll
consider it along with a plain switch.

--
rgds,

Pete
-------
"If Julia is the answer, then what was the stupid question!"

 

[Sylvia Else]

On 13/05/2013 10:29 AM, felix_unger wrote:

In that case you will need good quality audio leads. However no 'true'
audiophile would want anything less than digital audio I would suggest.

True audiophiles recognise that digital is a quantised approximation to
the true waveform, and that only analogue media are up to the task of
faithful reproduction.

Sylvia.

 

[felix_unger]

On 13-May-2013 10:45 AM, Sylvia Else wrote:

On 13/05/2013 10:29 AM, felix_unger wrote:


In that case you will need good quality audio leads. However no 'true'
audiophile would want anything less than digital audio I would suggest.

True audiophiles recognise that digital is a quantised approximation
to the true waveform, and that only analogue media are up to the task
of faithful reproduction.

That's true of course for dedicated audio systems for music
reproduction. However, when it comes to Audio/Video systems (surround
sound 5.1, 6.1, 7.1) for watching movies there's no comparison in sound
quality, if only for the fact that analogue audio is only stereo.

Sylvia.

--
rgds,

Pete
-------
"If Julia is the answer, then what was the stupid question!"

 

[Coach]

On May 11, 9:02 am, "DavidW" <n...@email.provided> wrote:

Bob Milutinovic wrote:
"DavidW" <n...@email.provided> wrote in message

I misunderstood then. I thought you were suggesting a "switch" that
would solve the signal-loss problem while maintaining the two
simultaneous connections. A passive switch was my first thought and
what I'll probably go with, but parallel connections would be better
for my purpose so I thought I'd ask.

As Brad and Sylvia have said, you'll have issues with the video
signal - not enough to prevent you from seeing it on both outputs,
but more than enough to drag the video quality into the mud (remember
making copies of copies of VHS tapes, and how good the resulting
recording was?).

If you have $47 to spare, grab this; it'll do the job properly for
both audio and video, and has four outputs rather than just two;
http://www.ebay.com.au/itm/121073559070

If you want to save a bit of money and have a 12V power supply of
reasonable grunt laying around (1A output should suffice), this one
does just the video for $14;http://www.ebay.com.au/itm/261190349984

Audio isn't a problem unless you're wanting genuinely high fidelity
(which I suspect you're not); as Sylvia points out, most amplifiers
have a comparatively high input impedance (generally several tens of
kiloohms or higher), so there won't be any noticable signal
degradation.

As an audiophile I do want <snipped the rest

I always suspected you were one. My 6th sense is rarely wrong. Stay
away from primary schools you sicko.

 

[Trevor]

"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:avardcFslfpU2@mid.individual.net...

On 13/05/2013 10:29 AM, felix_unger wrote:
In that case you will need good quality audio leads. However no 'true'
audiophile would want anything less than digital audio I would suggest.

True audiophiles recognise that digital is a quantised approximation to
the true waveform, and that only analogue media are up to the task of
faithful reproduction.

True idiots you mean, those that actually have a clue (perhaps not such a
big percentage admittedly) know that after adding dither and a
reconstruction filter, there is no quantitisation remaining, only a FAR more
accurate signal than can be obtained by ANY analog recording method
available.

Trevor.

 

[Sylvia Else]

On 13/05/2013 2:05 PM, Trevor wrote:

"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:avardcFslfpU2@mid.individual.net...
On 13/05/2013 10:29 AM, felix_unger wrote:
In that case you will need good quality audio leads. However no 'true'
audiophile would want anything less than digital audio I would suggest.

True audiophiles recognise that digital is a quantised approximation to
the true waveform, and that only analogue media are up to the task of
faithful reproduction.

True idiots you mean, those that actually have a clue (perhaps not such a
big percentage admittedly) know that after adding dither and a
reconstruction filter, there is no quantitisation remaining, only a FAR more
accurate signal than can be obtained by ANY analog recording method
available.

Trevor.

Of course, but you should never smarten up a chump.

Audiophiles in the UK used to cite the BBC's Radio 3 (a classical music
channel) FM service as the gold standard for analogue purity, blissfully
unaware that the BBC was using digital technology to get the signal from
its studios to the transmitters.

Sylvia.

 

[Trevor]

"felix_unger" <me@nothere.com> wrote in message
news:avatpfFt51gU1@mid.individual.net...

On 13-May-2013 10:45 AM, Sylvia Else wrote:
In that case you will need good quality audio leads. However no 'true'
audiophile would want anything less than digital audio I would suggest.

True audiophiles recognise that digital is a quantised approximation to
the true waveform, and that only analogue media are up to the task of
faithful reproduction.

That's true of course for dedicated audio systems for music reproduction.

Nope, not for any modern digital audio system that isn't broken.

However, when it comes to Audio/Video systems (surround sound 5.1, 6.1,
7.1) for watching movies there's no comparison in sound quality, if only
for the fact that analogue audio is only stereo.

I'd still prefer two HiFi channels to 7.1 low fi channels. Fortunately both
can easily be HiFi, even if they often aren't.

Trevor.