I want to place my TV/DVD/VCR in the opposite corner of my room from where
the rest of my audio gear is...I would need 30 foot RCA cables...Is this bad?
What are alternatives, especially inexpensive ones?

------------------------------------------------------------------------
Andy Yee E-Mail: ayee AT mn dot rr dot com
President Home Page: http://home.mn.rr.com/andyyee
New Directions Engineering, Inc.

Godwin's Law: As a USENET thread grows, the probability of a reference
to Hitler or Nazis approaches 1.00.
Corollary: When such a reference is made, it is generally
recognized that the poster has LOST the argument.

Andy Yee wrote:

I want to place my TV/DVD/VCR in the opposite corner of my room from where
the rest of my audio gear is...I would need 30 foot RCA cables...Is this bad?
What are alternatives, especially inexpensive ones?

There are several factors to consider when running "long" unbalanced lines,
including high frequency loss, ground loop hum, and induced noise.

High frequency loss occurs because the capacitance of the cable and the
output impedance of the device driving the line form a low-pass/high-cut
filter. The lower the source impedance and cable capacitance, the higher
the cutoff frequency. With most modern gear and decent cables, this is
not an issue for 30 feet of cable.

Ground loop hum occurs when the devices at each end of the cable are
grounded thru seperate paths and therefore are at different ground
potentials. When this happens, the common/shield/ground of the device
receiving the signal is driven with an AC voltage equal to the potential
difference of the two grounds. Because that device uses that part of
the line as its reference voltage (I.e., it assumes that the shield is
zero volts.), the receiving device sees the difference in grounds as
a 60 Hz signal, resulting in hum. Whether this will be a problem depends
on the grounding situation in the rooms of your home.

Induced noise occurs when an unbalanced line runs near a source of
magnetic or electrostatic interference such as a lamp dimmer, a
transformer (Such as those used in many wall warts.) or an electric
motor. You can reduce the effect of induced noise by routing the line
to avoid such devices.

The bottom line is that 30 feet is not all that long, but you may or
may not have problems depending on several factors. If you do have
problems, their solutions depend on their nature.

--
================================================== ======================
Michael Kesti | "And like, one and one don't make
| two, one and one make one."
mrkesti at comcast dot net | - The Who, Bargain

Andy Yee wrote:

I want to place my TV/DVD/VCR in the opposite corner of my room
from where the rest of my audio gear is...I would need 30 foot
RCA cables...Is this bad?

No. At a guess it is beyond 100 feet that you start to worry about what
you drive the cable with. The basic spec to look for is output impedance
of originating apparatus, it is generally less than 1000 Ohms nowadays,
and possibly 100 to 50 Ohms.

What are alternatives, especially inexpensive ones?

I would however prefer to use a quality mic cable. For long stretches,
ie. hundreds of feet, it can be better to use a headphone output since
it is designed to tolerate very low load impedances. You will know it if
you need to use balanced cabling, a low source impedance is generally
fairly uncritical.

Andy Yee E-Mail: ayee AT mn dot rr dot com


Kind regards

Peter Larsen

--
*******************************************
* My site is at: http://www.muyiovatki.dk *
*******************************************

"Peter Larsen" wrote in message
...
What are alternatives, especially inexpensive ones?

I would however prefer to use a quality mic cable.

Quality mic cables are balanced.

For long stretches,
ie. hundreds of feet, it can be better to use a headphone output since
it is designed to tolerate very low load impedances. You will know it if
you need to use balanced cabling, a low source impedance is generally
fairly uncritical.

If his output and input are unbalanced, then going to balanced and back is
NOT likely to be an "inexpensive" solution.

MrT.

"Mr.T" wrote:

snip

If his output and input are unbalanced, then going to balanced and back is
NOT likely to be an "inexpensive" solution.

I suppose that depends on one's threshold of expensive. Assuming stereo,
two each of Radio Shack's 274-016 and 274-017 come to $60, not counting
the cables.

BTW, these are two of the few Radio Shack items I have ever suggested are
worth purchasing. It's been about 15 years since I bought any, though, and
would not be at all surprised to learn that they are now using a cheaper
transformer and that I might now regret suggesting them. Others, such as
Shure Bros. and ProCo, make similar products that don't cost too much
more and are probably less of a gamble to purchase.

--
================================================== ======================
Michael Kesti | "And like, one and one don't make
| two, one and one make one."
mrkesti at comcast dot net | - The Who, Bargain

Michael R. Kesti wrote:
two each of Radio Shack's 274-016 and 274-017 come to $60, not counting
the cables.

I've done exactly this when I've had to run a line-level feed to a
remote amp and speakers. (Break-out room and similar.) Some of those
have been runs of several hundred feet out the door, across the hall,
into the stairwell, up two or three floors, down the coridor...)

"Michael R. Kesti" wrote in message
...
I suppose that depends on one's threshold of expensive. Assuming stereo,
two each of Radio Shack's 274-016 and 274-017 come to $60, not counting
the cables.

Agreed, but it's still more than the cost of his soundcard I think, and will
introduce some level of degradation. But it is an option.

MrT.

"Mr.T" MrT@home wrote in message
u
"Michael R. Kesti" wrote in message
...
I suppose that depends on one's threshold of expensive.
Assuming stereo, two each of Radio Shack's 274-016 and
274-017 come to $60, not counting the cables.

Agreed, but it's still more than the cost of his
soundcard I think, and will introduce some level of
degradation.

I share your concern about degradation. Cheap audio
transformers have a long history of introducing sonic
degradation.

But it is an option.

First he should try plain old wire.

In article , Andy Yee wrote:
I want to place my TV/DVD/VCR in the opposite corner of my room from where
the rest of my audio gear is...I would need 30 foot RCA cables...Is this bad?
What are alternatives, especially inexpensive ones?

------------------------------------------------------------------------
Andy Yee E-Mail: ayee AT mn dot rr dot com

The biggest problem is ground loops. Isolators and balanced lines get rid of this.
I've seen some RCA cables with extremly high capacitance. The normal
ones are not too bad. When I want extra low capacitance I use RG62 coax
to make RCA's.

greg

"Mr.T" wrote:

"Peter Larsen" wrote in message
...
What are alternatives, especially inexpensive ones?

I would however prefer to use a quality mic cable.

Quality mic cables are balanced.

That surely depends on what plugs you solder on to them and how.

For long stretches,
ie. hundreds of feet, it can be better to use a headphone output since
it is designed to tolerate very low load impedances. You will know it if
you need to use balanced cabling, a low source impedance is generally
fairly uncritical.

If his output and input are unbalanced, then going to balanced and back is
NOT likely to be an "inexpensive" solution.

I made no such suggestion, I explained why it is likely to work without.
Balancing is btw. not all that costly

MrT.

Thank you for making the clarification relevant, I should have written
more precisely.


Kind regards

Peter Larsen


--
*******************************************
* My site is at: http://www.muyiovatki.dk *
*******************************************

"Peter Larsen" wrote in message
...
I would however prefer to use a quality mic cable.

Quality mic cables are balanced.

That surely depends on what plugs you solder on to them and how.

If it has no plugs, then it is co-ax cable, twin screened cable, star quad
cable etc. Not really a *microphone* cable, but lets not get into a nit
picking argument.


If his output and input are unbalanced, then going to balanced and back
is
NOT likely to be an "inexpensive" solution.

I made no such suggestion, I explained why it is likely to work without.
Balancing is btw. not all that costly

Thank you for making the clarification relevant, I should have written
more precisely.

Fair enough, but a mic cable will not necessarily be better than a quality
single core screened cable for unbalanced purposes. And using the two cores
of a mic cable for stereo, is not as good as using separate cables for each
channel, or even two core individually screened figure 8 co-ax.

Can you clarify why mic cable would be better?

MrT.

Would I need any impedance converters? Or could I just find an RCA-RG62
adapter?

(GregS) wrote in
:

The biggest problem is ground loops. Isolators and balanced lines get
rid of this. I've seen some RCA cables with extremly high capacitance.
The normal ones are not too bad. When I want extra low capacitance I use
RG62 coax to make RCA's.


------------------------------------------------------------------------
Andy Yee E-Mail: ayee AT mn dot rr dot com
President Home Page: http://home.mn.rr.com/andyyee
New Directions Engineering, Inc.

Godwin's Law: As a USENET thread grows, the probability of a reference
to Hitler or Nazis approaches 1.00.
Corollary: When such a reference is made, it is generally
recognized that the poster has LOST the argument.

"Andy Yee" wrote ...
Would I need any impedance converters? Or could I just
find an RCA-RG62 adapter?

No "impedance converters" needed for audio use.

In article , Andy Yee wrote:
Would I need any impedance converters? Or could I just find an RCA-RG62
adapter?

(GregS) wrote in
:

The biggest problem is ground loops. Isolators and balanced lines get
rid of this. I've seen some RCA cables with extremly high capacitance.
The normal ones are not too bad. When I want extra low capacitance I use
RG62 coax to make RCA's.


You just need a correct sized RCA. I have use the solder crimp combo.
You need to solder the inner, and crimp the outside.

greg

In article , (GregS) wrote:
In article , Andy Yee
wrote:
Would I need any impedance converters? Or could I just find an RCA-RG62
adapter?

(GregS) wrote in
:

The biggest problem is ground loops. Isolators and balanced lines get
rid of this. I've seen some RCA cables with extremly high capacitance.
The normal ones are not too bad. When I want extra low capacitance I use
RG62 coax to make RCA's.


You just need a correct sized RCA. I have use the solder crimp combo.
You need to solder the inner, and crimp the outside.

greg

MCM Electronics part number # 27-570

(GregS) wrote in news:dlieja$54d$1
@usenet01.srv.cis.pitt.edu:

27-570

So...Coax cable would be better at keeping noise and hum off a low-level
signal that is unbalanced?

------------------------------------------------------------------------
Andy Yee E-Mail: ayee AT mn dot rr dot com
President Home Page: http://home.mn.rr.com/andyyee
New Directions Engineering, Inc.

Godwin's Law: As a USENET thread grows, the probability of a reference
to Hitler or Nazis approaches 1.00.
Corollary: When such a reference is made, it is generally
recognized that the poster has LOST the argument.

"Andy Yee" wrote ...
So...Coax cable would be better at keeping noise and hum
off a low-level signal that is unbalanced?

A low-level, unbalanced signal REQUIRES a shielded wire
("coaxial") to survive for any distance in the real world.
A coaxial cable is "better" in the same sense that a bottle is
"better" at holding water than your hat. But balanced is still
preferable for sending low-level signals over long distances.

"Mr.T" wrote:

"Peter Larsen" wrote in message
...
I would however prefer to use a quality mic cable.

Quality mic cables are balanced.

That surely depends on what plugs you solder on to them and how.

If it has no plugs, then it is co-ax cable, twin screened cable, star quad
cable etc. Not really a *microphone* cable, but lets not get into a nit
picking argument.

Then don't.

Thank you for making the clarification relevant,
I should have written more precisely.

Fair enough, but a mic cable will not necessarily be better
than a quality single core screened cable for unbalanced purposes.

It is in my opinion cost efficient and constructed with durability in
mind.

And using the two cores of a mic cable for stereo, is not as
good as using separate cables for each channel,

That depends on the source impedance and also on what amount of loss of
channel separation as may be acceptable. You may want to check up on
what accepted for grammophone pickup cartridges and for FM tuners and
then perhaps worry less, unless independent channels are required. Such
a cable should however, as any long cable, be driven by an independently
buffered output and not just by "any" tape output socket since it may
then influence what passes through to the main sound output of the
primary system.

or even two core individually screened figure 8 co-ax.

Hmmm ....

Can you clarify why mic cable would be better?

Yes, you can dance on it with clogs and it will still pass signal.
Experimentally determined by many roadies. It seems relevant that
cabling for a fixed "other room" installation, such as this appears to
be about, should be sturdy and have good longevity. Mic cables also tend
to have good RF screening and to offer a modest capacitive load.

MrT.


Kind regards

Peter Larsen

--
*******************************************
* My site is at: http://www.muyiovatki.dk *
*******************************************

"Peter Larsen" wrote in message
...
Fair enough, but a mic cable will not necessarily be better
than a quality single core screened cable for unbalanced purposes.

It is in my opinion cost efficient and constructed with durability in
mind.

As is similar quality single core cable.

And using the two cores of a mic cable for stereo, is not as
good as using separate cables for each channel,

That depends on the source impedance and also on what amount of loss of
channel separation as may be acceptable. You may want to check up on
what accepted for grammophone pickup cartridges and for FM tuners

Hardly the same length runs as we are currently discussing. However channel
seperation is not great in those cases to start with.

Can you clarify why mic cable would be better?

Yes, you can dance on it with clogs and it will still pass signal.

Then you really need a steel reinforced cable, which most mic cables are
not.

Experimentally determined by many roadies.

Of course, that's what they have readilly to hand.

It seems relevant that
cabling for a fixed "other room" installation, such as this appears to
be about, should be sturdy and have good longevity. Mic cables also tend
to have good RF screening and to offer a modest capacitive load.

As does similar quality single core cable.
If you prefer to use twin core mic cable because you already have it on
hand, fair enough, but no need to pretend it has mystical qualities not
obtainable in a single core cable.

MrT.