Hydrogenaudio Forums > cables making a difference?

krabapple

Mar 26 2008, 11:34

anyone seen this?

http://www.planetanalog.com/showArticle.jh...cleID=201807797

the money shots are figs 6.8 and 6.9.

QUOTE

However, when they replaced the 8 ohm resistive load with a passively crossed-over loudspeaker system, they were surprised to see the results as shown in Figure 6.8. With the more complex load, all the plots had changed. After changing the load to the low frequency loudspeaker, all the plots changed again, as shown in Figure 6.9.

The distortion patterns were noticeably different, not only between the cables, but also between the input and output ends of each cable. The implication here is that the cables change the way that the complex load is seen by the amplifier. Voishvillo reported that upon seeing this, Czerwinski exclaimed "But they're only short cables!"

Being touted of course by subjectivists that cables sound different.. but seems to me the Romex before/after are very similar, while the other two may be 'broken' by comparison.

pdq

Mar 26 2008, 11:51

OK, so we know that a speaker is not a resistive load. It has mass and generates back emf. This should hardly be a surprise.

Woodinville

Mar 26 2008, 23:24

QUOTE(krabapple @ Mar 26 2008, 10:34)

anyone seen this?

http://www.planetanalog.com/showArticle.jh...cleID=201807797

the money shots are figs 6.8 and 6.9.

QUOTE

However, when they replaced the 8 ohm resistive load with a passively crossed-over loudspeaker system, they were surprised to see the results as shown in Figure 6.8. With the more complex load, all the plots had changed. After changing the load to the low frequency loudspeaker, all the plots changed again, as shown in Figure 6.9.

The distortion patterns were noticeably different, not only between the cables, but also between the input and output ends of each cable. The implication here is that the cables change the way that the complex load is seen by the amplifier. Voishvillo reported that upon seeing this, Czerwinski exclaimed "But they're only short cables!"

Being touted of course by subjectivists that cables sound different.. but seems to me the Romex before/after are very similar, while the other two may be 'broken' by comparison.

Hm, more information could suggest if that might rise above a masking threshold or not. At least on my screen all I see is really teensy-tiny lines. Maybe it's my old-guy eyes.

I would not doubt that the smaller wire shows more distortion from the back EMF, but is there some reason we ought to find this surprising????

krabapple

Mar 28 2008, 12:23

CLick on any of the graphs, it takes you to a larger version of them -- in Firefox you can then also magnify them some more.

e.g.

http://i.cmpnet.com/audiodesignline/2007/0...kers_fig6.8.gif

Woodinville

Mar 28 2008, 14:24

QUOTE(krabapple @ Mar 28 2008, 11:23)

CLick on any of the graphs, it takes you to a larger version of them -- in Firefox you can then also magnify them some more.

e.g.

http://i.cmpnet.com/audiodesignline/2007/0...kers_fig6.8.gif

Mutter. Blocked from work. Mutter.

From home:

Said plots are very uninformative, I think. There is no solid reference, I don't see the plot of the original tone, and it's very hard to know the actual meaning of these plots.

What's more, again, what appears to be the fattest cable shows the least difference, and the level of distortion at the input to the cable, itself, seems, well, interesting.

More work, and a better writeup, as well as equipment verification, seems minimal here.

And, of course, 6 meters ~= 20 feet. This is "short" only in their imagination.

Paulhoff

Mar 29 2008, 13:04

I will throw away my ham radio equipment, how the hell does it ever work at millions of hz.

Paul