Speaker Cable

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Thanks DF96.

So, is the following quote correct?

Damping factor is, indirectly, a measure of output impedance. If an amplifier has an output impedance of 1 Ohm and it drives an 8 Ohm loudspeaker, then the damping factor is 8 (i.e. loudspeaker impedance divided by output impedance). Of course, if a 4 Ohm loudspeaker is connected it becomes 4, suggesting damping has decreased, when in fact output impedance remains the same.
 
Yes, provided that the 8 and 4 are nominal speaker impedances. Note that putting a 4 ohm speaker on the amp means that damping probably has decreased.

Basically, DF is an attempt to quantify output impedance in a way which looks impressive but is easy to grasp by nontechnical people. 'DF=80' looks so much better than 'output impedance=0.1 ohms'. 'DF=160' looks even better (twice as good?), but in fact it is well into the realm of diminishing returns. As I said, damping varies something like 1 +1/DF.
 
That's a good summing up DF96!

Allow me to add the information I have unearthed in the hope that it will assist others unfamiliar with the topic.

The output impedance of the typical transistor amp is very low, due to the use of negative feedback, and the damping factor consequently so high that it doesn't pose an issue.

Valve amps have higher output impedances leading to lower damping factors which may be an issue, particularly in relation to Single Ended designs with zero feedback.

The secret lies in matching loudspeaker to amplfier. Under damped loudspeakers are best coupled with transistor amps, while over damped loudspeakers are best suited to valve amplifiers.

This is where active speakers have the advantage, as the matching has already been done for you!
 
DON'T PANIC!!

I'm after suggestions based on aesthetics and practicality please.....

My speakers get moved around a lot, most of the time they are in the middle of my room. The floor is cork tiles. I want a very flexible cable that will stand being moved a lot and lie flat without complaining, and that will also blend with the floor colour to a degree. I like the look of this https://www.lampspares.co.uk/3-core...Gsr5g7TwkdAa_CAeu7CflR_AeEDc4ruBoC8BQQAvD_BwE but am open to all suggestions/advice. Thanks.
DSCk
This is competent cable and lies flat. It isn't cork coloured so you'd have to paint it. Maybe they do a transparent version.
 
No, DF is defined using speaker nominal impedance not actual impedance at any particular frequency.
The Wikipedia definition seems a little ambiguous, it talks about using only the resistive part of the impedance, then later goes on to say

"A high damping factor indicates that an amplifier will have greater control over the movement of the speaker cone, particularly in the bass region near the resonant frequency of the driver's mechanical resonance. However, the damping factor at any particular frequency will vary, since driver voice coils are complex impedances whose values vary with frequency."

Reading around it does seem to be largely a made up term for marketing purposes. I'll probably use 0.75mm to be on the safe side
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.