Lowest resistance speaker wire

[wiseoldtech]

Theses amp are designed for use with speakers that are no more than 2 meters away from the amplifier connected via audiophile quality speaker wire and connectors that probably have a low resistance. To a speaker that’s probably 8ohms.

Just because the dampening factor starts at the number 14 doesn’t mean it ends at that number once everything else is considered.

But would you really connect that amp up to a 4ohm 15” sub 7 meters away? I don’t think so.

I think a 15 inch monster sub would need an amp with more control over its cone than some floor standing speakers in smallish cabinets.

Those, and other McIntosh amps, use a tapped autotransformer for speaker output, surely you already knew that.
As for the MC2300, it was built for stage use, multiple ones ran speaker systems far across and above the stage in outdoor venues.

 

[schiirrn]

Yup, there is no U anywhere in the formulas. When voltage driven the speaker voice coil acts as U/I converter. A nonlinear one.


(more of a question than a statement: if DF mattered then, if the Q of a speaker system is measured, wouldn't the result depend on the DF of the amplifier used?)

Sorry.... i dont want to upset anyone.
But let me explain in short the physics, this forum is primarily for education isn´t it?

Regarding really high output impedance, trans conductance or current drive. I have just built some after the schematics here:
Joe Rasmussen "Trans-Amp" - 40 Watt Transconductance "Current Amplifier"

If we listen to the theory that extremely LOW output impedance is "the best" thing... How come that 270 ohms output impedance really outperformed my Bryston 4B amplifier in my active driven hifi system? I have had several listening sessions here confirming that the woofers play deeper, more powerful, and less colored?

This is how it works.
The force F acting upon the membrane comes from the current I of the voice coil wire length L that moves in the magnetic gap adn the field B with the formula F= B*I*L
L and is fixed parameters defined by the construction of the magnetic drive system. So we see that the force F is directly proportional to I current. The speaker is by it´s construction CURRENT DRIVEN and NOT voltage driven. The transconductance amplifier transforms the voltage signal (nice music hopefully) to a current! That we by definition wanted right? This works well in an active loudspeaker system where no other passive crossovers is involved. Thats why this construction isn´t very common, and this is not for every one since you have to do some adjustments to get it work properly (oscillation). The side effect is the you can reduce the distortion of the woofer from 20% to 2%, that means with factor 10 . That is coloration we are talking about, that is smearing out details and ADDING harmonics that is not present in the music signal from the beginning. So where does this distortion comes from and how is it reduced by a strange amplifier topology that none uses?
When the signal current induces a magnetic field around the voice coil, eddy currents in the pole pieces is generated and creates voice coil position impedance variations. Also the voice coil current heats up the copper which in turn increases the resistance and adds compression. And the voice coil itself has 6 ohms resistance when its cold, after some minutes it reaches 6,2 ohms.... A current amplifier will correct this!
It will continue to move the speaker even if the resistance is changing to 10ohm!
If you have a cable with 0.0001 ohm or 3 ohms it will play exactly the same with current drive! The other benefits I can mention another day.