Cable burn in

Yes… you are right I have fallen into the trap, like many articles on the web, of thinking the output inductor is part of the Zobel network, or Boucherot cell… it isn’t… the inductor is to dampen NFB instability caused by load capacitance… which Naim use loudspeaker cable for in classic designs, and is quite separate from the Zobel network or Boucherot cell.

However Douglas Self’s excellent texts on amplifiers has re educated me.

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                      BURN IN.

HOMEWORK. CLASS 2B.
TEACH: JOHNNY What did you do? Answ, UM! UM is not an answer SIT DOWN!
GEORGINA How did you go? Answ, Well i got a new cable put a signal through it
and Photographed it live. TEACH: You Dont Say! What did you do next? Answ, We
burned it in for 50 hrs and did another Photo of the signal. TEACH: REALLY! Answ,
Yes we used an ELECTRON MICROSCOPE and we expect any variation in the Videos
will confirm burn in. TEACH; Well you certainly know your subject! Much better than
JONNYS idea of using a Modified Crystal Set and rubbing 2 sticks together to measure it.
OK You have finished that Project so Class DISMISSED! WAIT!! WAIT!! Dont forget
next Tuesday we are doing FLYING SAUCERS!

We think 50 hours is too short time to burn in a cable. Try 500 hours next time.

That is a pretty silly answer from someone who does not know if burn in exists.

          COPPER WIRE

99.9999% Purity AKA 6-9s. Science claims this benefits “Signal Transfer” So it therefore follows a Audio Signal will benefit. Now this is purely a Science claim as i have not heard of anyone who can actually hear this difference.
So is this a claim for a “signal transfer benefit” that can not be measured ?
Because if it is prepared to deny things people can actually hear because it can not measure
them, is this not a double standard?
Not that i would accuse anyone of cheating mind you.

Where?

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Where is this scientific claim referenced… I have never heard of it so am curious…

From Google:

Standard copper wire is around 99.95% pure, 0.03% O2, and less than 50 ppm metallic impurities. It has a high electrical conductivity, in excess of 100% IACS.

Now the conductivity of the connectors is probably a lot lower, for instance gold has IACS of around 70%.

With this knowledge, is it reasonable to expect that ‘special’ copper wire at 99.9999% purity will offer clear and audible improvements in signal transfer? Meaning that for every 10,000 electrons passing through the cable, it might be able to move 4 or 5 more?

It is highly unlikely. It doesn’t really matter if there are 2 or 6 ‘nines’ after the comma, since it will still round to roughly the same amount of electrons passing through.

So i don’t really expect any scientist to make that claim…

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No… almost certainly not… signal transfer will be influenced far more by electromagnetic effects, stray impedances and geometric effects rather than minute impurities at the atomic scale…

I guess where I struggle with many Hi-Fi enthusiast debates on signal transfer on wires is they nearly always seem to assume the wire is isolated and omit the source and sink conduction circuitry and effects which the wire then becomes part of which has a complete encyclopaedia of influences and effects that do influence signal transfer in a meaningful way and a way that needs to be managed and designed for.

So why this obsession of wire purity, say compared to the value, construct and purity of the Miller effect capacitor(s) in gain compensation circuitry… or even the design of PCBs and connected wires to mitigate stray inductance and capacitance which have a significantly more notable effect on signal transfer.

It too has many alternate approaches… a high quality audio amplifier is a catalogue of compromises and design choices… and tends to have methods and approaches that are documented in engineering, scientific papers as well as patents… and is constantly evolving… it all started with very early long distance telephone repeaters and hasn’t stood still since.

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True… and as i mentioned in the post before, the conductivity of for instance gold plated connectors is around 30% lower than that of a copper cable itself. So i’m guessing that the manufacturers concluded that the conductivity is not the most important factor, in the grand scheme of things.

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Exactly. Resistance to corrosion is a consideration etc. Also…notice how speaker manufacturers don’t make a big fuss about the wires they use within their speakers to connect the drivers to the crossovers? Have you seen what they use!!! It’s normally absolutely rubbish.

Resistance, reactive capacitive and inductive impedance will be relevant… but relevance doesn’t mean the cable has to look boutique… it can equally look plain and industrial… as most wires and cables away from consumer prying eyes do.

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Guys,

Please remember that copper is better conductor than gold (and less than silver).

And (as usefully noted) gold is used for corrosion protection.

I believe.

Not to mention, the solder, the component lead outs etc, but I do agree that capacitors are probably responsible for most of the unwanted effects in commonly produced audio, hence some designers obsession with removing them from the signal chain.

People are interested in cables because they can easily change them.

Again another myth… exactly what is meant by the signal chain… most amplifiers use feedback to control the effects temperature and minimise distortion… capacitors are used here to control stability and bandwidth gain… and are by definition part of the signal chain… without it amps would be unstable and/ or sound awful.

I think they mean reduce series shunt capacitors so as to DC couple… but that is not the same as removing them from the signal chain.

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I think people like to experiment.

Making experiments with cables is less expensive than making experiments with amplifiers.

If it was the opposite, everybody would be changing amplifiers all the time, and would keep their cables in place.

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That is exactly it in my opinion, although tinkering is perhaps more appropriate than experimenting. Changing cables requires to application of thought or understanding… just perhaps deep pockets… and the prettier they look I’m sure the better they sound.

To your last point, you can relatively easily undertake changes here as well with some applied thought… it’s not really that mystical…, that can be quite interesting… but such discussions are not supported on this forum.

Yes I think this is what I had gauged from various articles. I tend to treat my input to this place with some whimsy as there are other places where they like to discuss the inner workings.

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Including my very effective Mogami 2497 DIN to XLR interconnects!

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Indeed, I am suspicious, of any cable which is adorned with fancy braids and ‘attachments’, or arrive in a fancy wooden box with faux silk lining, they smack of beautification to justify the high price to me.

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