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Message: <blockquote data-quote="Peter Morris" data-source="post: 145775" data-attributes="member: 652">Re: Damping Factor - Actual listening tests?Hi Jason,If you have not already, I would suggest you read some of the papers that have been referenced in this thread.As requested here is a slightly more complex answer ….You can represent a speaker as having 3 parts – the Electrical circuit, the Mechanical circuit and the Acoustic circuit - refer picture 1If you apply a voltage to a speaker the voice coil will start to move in the magnetic field. The movement of the voice coil in a magnetic field will generate a Back-EMF.This EMF will be seen by the amp’s output circuitry. The amplifier will be the main electrical load on the “voice coil current generator” and result in "damping".For a given speaker, the amount of damping can be varied by changing the value of the external resistance Re (amplifier plus cables/connector) and consequently the value of the braking current.There a point where things are critically damped.  At this point transient distortion is reduced and the low-frequency response is more consistent. For a loud speaker this point is generally with Re as low as possible - remember that there is also Revc in the equation.Think of your cars suspension.  It’s a spring and a shock absorber (dampener) – a simple second order system. There is a point where there is the optimum value of the spring force and damping force.  If the spring force is too high with respect to the damping force the car will bounce up and down too much when you go over a bump, if it’s too low the wheels will not return to the correct position as soon as possible.  The second picture is the response of a second order system. Critically damped is with T = 1Loudspeaker systems are more complex than a typical second order system, but the principle is the same.In simple terms if Re is increased too much the system will look a bit like T less than 1.  In practice  the simple answer in 2015 is keep your speaker lead resistance as low as REASONABLY practical.  It shouldn’t be an issue unless you are doing something REALLY EXTREME.</blockquote>

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