A thread on another group suggested that these are the norm today. Not
being one who avidly reads the Hi-Fi press, is this so? The poster was
adamant it was the *only* way to feed 5.1 speakers etc that have internal
amps, as unbalanced would cause hum etc. This was from the US, though.

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Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...

A thread on another group suggested that these are the norm today. Not
being one who avidly reads the Hi-Fi press, is this so? The poster was
adamant it was the *only* way to feed 5.1 speakers etc that have internal
amps, as unbalanced would cause hum etc. This was from the US, though.

Can't say I've noticed balanced connections on domestic equipment. Are 5.1
speakers normally powered?, the only area where powered speakers seem to be
the norm are as computer speakers, and they never, IME, use balanced
interconnects.

David.

In article ,
David Looser wrote:
A thread on another group suggested that these are the norm today. Not
being one who avidly reads the Hi-Fi press, is this so? The poster was
adamant it was the *only* way to feed 5.1 speakers etc that have
internal amps, as unbalanced would cause hum etc. This was from the
US, though.

Can't say I've noticed balanced connections on domestic equipment. Are
5.1 speakers normally powered?, the only area where powered speakers
seem to be the norm are as computer speakers, and they never, IME, use
balanced interconnects.

This poster was talking about an AV preamp where all the power amps are
external. Nothing wrong with balanced of course - it's the pro standard -
but a bit OTT for domestic use.
The thread was about earth loops and he is convinced balanced is the only
way round. Could be in the US all metal cased equipment has to have a
mains safety ground - nothing about their electrics would surprise me. ;-)

I've got an elderly AV amp - and if you replaced all the phonos with XLRs
it would fill the room. ;-)

--
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Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)"

This poster was talking about an AV preamp where all the power amps are
external. Nothing wrong with balanced of course - it's the pro standard -
but a bit OTT for domestic use.
The thread was about earth loops and he is convinced balanced is the only
way round. Could be in the US all metal cased equipment has to have a
mains safety ground - nothing about their electrics would surprise me. ;-)


**The USA is just like everywhere else - i8e flooded with Asian made audio
gear that is Class 2 or Double Insulated.

So no main earth conductor in the AC cord.

As usual - your anonymous Septic poster is an utter ****wit.



....... Phil

In article ,
Phil Allison wrote:

"Dave Plowman (News)"

This poster was talking about an AV preamp where all the power amps
are external. Nothing wrong with balanced of course - it's the pro
standard - but a bit OTT for domestic use. The thread was about earth
loops and he is convinced balanced is the only way round. Could be in
the US all metal cased equipment has to have a mains safety ground -
nothing about their electrics would surprise me. ;-)


**The USA is just like everywhere else - i8e flooded with Asian made
audio gear that is Class 2 or Double Insulated.

That's what I'd guessed. Can't see why they'd make things worse for the US.

So no main earth conductor in the AC cord.

Yup.

As usual - your anonymous Septic poster is an utter ****wit.

I'm beginning to think so. But what the hell - at least it's about audio.
;-)



...... Phil

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Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
In article ,
David Looser wrote:
A thread on another group suggested that these are the norm today. Not
being one who avidly reads the Hi-Fi press, is this so? The poster was
adamant it was the *only* way to feed 5.1 speakers etc that have
internal amps, as unbalanced would cause hum etc. This was from the
US, though.

Can't say I've noticed balanced connections on domestic equipment. Are
5.1 speakers normally powered?, the only area where powered speakers
seem to be the norm are as computer speakers, and they never, IME, use
balanced interconnects.

This poster was talking about an AV preamp where all the power amps are
external. Nothing wrong with balanced of course - it's the pro standard -
but a bit OTT for domestic use.

I was looking at a Denon AV pre-amp a while back that had balanced outputs
to connect to external power amps. It was intended for the commercial
sector, but there's no reason why it couldn't be used domestically by those
with the space and the budget.

The thread was about earth loops and he is convinced balanced is the only
way round. Could be in the US all metal cased equipment has to have a
mains safety ground - nothing about their electrics would surprise me. ;-)

It's not necessary to go to full balanced to get over earth loop problems,
differential inputs connected to unbalanced outputs achieves the same thing.

I've got an elderly AV amp - and if you replaced all the phonos with XLRs
it would fill the room. ;-)

Indeed.

David.

David Looser wrote:

It's not necessary to go to full balanced to get over earth loop problems,
differential inputs connected to unbalanced outputs achieves the same thing.

An unbalanced output with equal value resistors in the hot and cold signal lines
( the cold going to equipment ground ) and a seperate screen IS balanced.
Normally just called 'impedance balanced' it provides almost all the advantages
of full-blown active balanced outputs. With a few more resistors it can even
'ground sense' and overcome hum caused by non-equipotential equipment grounds.

A differential ( balanced ) input takes a couple more resistors to make than an
unbalanced one.

PLUS the XLR is an excellent connector compared to the RCA.

Graham


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In article ,
Eeyore wrote:
PLUS the XLR is an excellent connector compared to the RCA.

I must be unique in not having problems with decent phonos. Apart from on
a Revox which got use a lot elsewhere so was constantly being unplugged.
But then the mains connector on that had to be replaced too. ;-)
They're really for semi permanent installation whereas an XLR is designed
for pro use on things which will be often unplugged.

But the main problem domestically is size - like to guess how many phonos
my AV amp has? ;-)

--
*I was once a millionaire but my mom gave away my baseball cards

Dave Plowman London SW
To e-mail, change noise into sound.

"Eeyore" wrote in message
...


David Looser wrote:

It's not necessary to go to full balanced to get over earth loop
problems,
differential inputs connected to unbalanced outputs achieves the same
thing.

An unbalanced output with equal value resistors in the hot and cold signal
lines
( the cold going to equipment ground ) and a seperate screen IS balanced.

Balanced in terms of impedance, not balanced in terms of signal voltage (and
hence it's ability to cause crosstalk in adjacent circuits). So I don't
think it correct to say it IS balanced. Having said that it is a perfectly
satisfactory arrangement for short runs and one I have used often.

Normally just called 'impedance balanced' it provides almost all the
advantages
of full-blown active balanced outputs. With a few more resistors it can
even
'ground sense' and overcome hum caused by non-equipotential equipment
grounds.

Not quite sure what you mean by that, a differential input naturally
overcomes hum caused by non-equipotential equipment grounds. This was made
very evident when a piece of video equipment of mine which has a
differential, unbalanced 75R co-ax input was fed from a video line which,
due to confusion about which is the neutral and which the earth pin on an
EP4 mains connector, was referenced to mains neutral, not earth. The
equipment worked fine with but the merest hint of a hum bar on the picture.

A differential ( balanced ) input takes a couple more resistors to make
than an
unbalanced one.

Indeed.

PLUS the XLR is an excellent connector compared to the RCA.

True, though a lot bigger and more expensive.

David.

"Dave Plowman (News)" wrote:

Nothing wrong with balanced of course - it's the pro standard -
but a bit OTT for domestic use.

Not at all. A balanced input and output can be made for mere pence more than
unbalanced ones and can solve a whole host of problems.

Graham


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to my email address