"Dave Plowman (News)" wrote in
:

In article ,
Rich.Andrews wrote:
For a piece of co-ax a couple of feet long or so to remove some of
the bass - which is what sounding thin means - would be quite an
achievement. Unless, of course there's been a small series
capacitor added somewhere.


Or possibly a resistor from the center conductor to ground.

Considering the low output impedance of well designed equipment, more
like a short? ;-)


There is some equipment that is well designed but designed to drive a
high impedance load. In cases like that, loading it down with 600 ohms
instead of something like 50k ohms will result in a roll off of low
frequencies.

In which case changing the interconnect will make not a scrap of
difference.


Provided the interconnect mfgr doesn't tie a resistor between the center
and ground or do anything else to lower the impedance.


r



--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.

"Jim Lesurf" wrote in message



I'm not sure if things have changed. However the normal assumption for
domestic audio sources in the 1970's and 1980's was that the source
(CD player, Tuner, etc) should work as per spec into loads down to
10kOhm in parallel with 1000 pF. The assumption being that any preamp
input would have an impedance that was this, or higher.

Agreed. AFAIK 10K and 1000 pF was the standard IHFM testing load for
line-level outputs. 1000 pF represents about 30 feet of standard shielded
cable.

So far as I know, 600 Ohm input impedance would be unusual in domestic
equipment.

600 ohm input impedance is unusual even in pro audio gear. Most pro audio
gear has an input impedance that is 2,000 ohms or above.

Although I think some items may use it with balanced inputs.

I know of no cases where pro audio gear has an input impedance that low.
Even mic inputs bottom out around 2K.

If so, I'd assume the source would then be expected to use a matching
output.

Most pro audio gear has an output impedance of 75-150 ohms, and can deliver
an undistorted +4 (abouit 1.25 volts) or greater into a 600 ohm load. Into
more typical loads, pro gear can delover 2 - 10 volts. Most pro gear can be
driven to full rated output with +4.

Hence in domestic practice. I would assume that having a 600 Ohm load
on a normal single-ended output would be unusual and not recommended.

Totally agreed.

Dave Plowman (News) wrote:

Have you got any examples of domestic equipment with an 600 ohm input
impedance?

An attenuating interconnect accidentally fitted back-to-front?

--
Eiron.

In article ,
Eiron wrote:
Have you got any examples of domestic equipment with an 600 ohm input
impedance?

An attenuating interconnect accidentally fitted back-to-front?

That's not the equipment, though?

--
*According to my calculations, the problem doesn't exist.

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

On Wed, 03 Nov 2004 19:19:51 GMT, mick wrote:

On Tue, 02 Nov 2004 19:44:33 +0000, Wally wrote:

Dan Abnormal wrote:

I've just
bought a Cyrus system and wonder whether it would be worth upgrading
from The Bay interconnects, which sound a little 'thin' now.

How do you know that the interconnects sound thin?

Measure the OD of one channel of the interconnect using a pair of external
callipers. Anything less than 4mm dia is thin... ;-)


You guys are so far up your own backsides. Thanks for trying to help
- in your own way(s). Happy Diwali ;-)

In article ,
Dan Abnormal wrote:
You guys are so far up your own backsides. Thanks for trying to help
- in your own way(s). Happy Diwali ;-)

You'll know about the large cash prize on offer for anyone who can tell
the difference between adequately specified cables? (this would be covered
by the ones supplied with most equipment)

And that no one has been able to win it?

If the difference was so obvious as some think - including the mags who
help to sell such things - it would be like taking candy off a child...

--
*He who laughs last, thinks slowest.

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

On Fri, 05 Nov 2004 22:00:33 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Dan Abnormal wrote:
You guys are so far up your own backsides. Thanks for trying to help
- in your own way(s). Happy Diwali ;-)

You'll know about the large cash prize on offer for anyone who can tell
the difference between adequately specified cables? (this would be covered
by the ones supplied with most equipment)

And that no one has been able to win it?

If the difference was so obvious as some think - including the mags who
help to sell such things - it would be like taking candy off a child...

The more interesting thing is that, despite much loudmouthed claiming
of 'night and day' differences, no one has even *tried* to claim that
cash. All mouth and no trousers is an old expression.............

--

Stewart Pinkerton | Music is Art - Audio is Engineering

In article , Stewart Pinkerton
wrote:


The more interesting thing is that, despite much loudmouthed claiming of
'night and day' differences, no one has even *tried* to claim that cash.
All mouth and no trousers is an old expression.............

I have been interested to see how this issue has been 'brushed aside' in
audio magazines on a few occasions in recent years. The response to
reader's letters who ask for some backup for claims about such differences
is to reply along the lines of, "It's obvious, so we can't be bothered."

This, of course, fails to address the point you make above. Curious that
non of the magazine reviewers want an easy thousand pounds. Writing for
the magazines isn't *that* profitable that you wouldn't bother to pick up a
1000 pound note you saw laying on the pavement. ;-)

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html