Low damping factor but fast& high current SS amps?

It's very simple to add a resistor in series with the output of an amplifier with a high damping factor (a.k.a. low output impedance) to get whatever damping factor you desire. The resistor value can be calcuated by dividing the nominal speaker impedance by the target damping factor value. So if you wish to have a damping factor of two, and your loudspeakers have a nominal impedance of 8 ohms . . . then placing a 4-ohm resistor in series will acheive the desired result.

Most audiophile parts suppliers have an assortment of resistors of the proper value - a non-inductive wirewound type is ideal, and a power rating of 20-50 watts will be more than adequate for the overwhelming majority of domestic applications.

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Liguy, did you cut and paste that from a tech for dummies web site?

I think it is a rather poor explanation because it is the magnetic field which damps the motion, not back EMF.

The amount of force it takes to move a generator (ringing speaker in this case) is proportional to how low the load is.

The lower the impedance the speaker sees looking back into the amp the more current it generates with its motion.

The more current it generates the stronger the magnetic field it generates which pushes back against the speakers magnetic field.

That's why speakers are often shipped with shorting straps across their terminals. This short allows a lot of current to flow when the speaker vibrates and dampens it. If you ever turned a hand generator you will find that the harder you crank and the lower the load the harder it gets. Not because of any back EMF, because the magnetic field from the current flow pushes back.

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All this talk of damping factor without a single tip of the hat to the 'q' of the speaker.
Critically damped speakers...Q-0.707 need much less amplifier damping.
Hi Q speakers can benefit from higher amp damping factor, but only to a point.

Electricity and magnetism are interchangeable. Think of a shorting strap as an amp with low resistance to the back EMF generated in the speaker.

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Electricity and magnetism are interchangeable.

Not at all, they go hand in hand but are entirely different beasts. It is the magnetic field generated by the current in the coil that is pushing against the speaker magnet that dampens the motion.

Something is pushing the coil in a direction opposite of the way it is traveling and that force is magnetic. There is no way to logically explain the phenomenon using back EMF. Back EMF is not pushing the speaker.

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In a dynamic system, I rather doubt you can have one without the other.

That the speaker generates the energy which damps its motion is without question.
And, since speakers store energy for later release, I'm not too uncomfortable calling it back EMF.......