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Just think about Ohm's Law in its entirety, but with the limitations of a using 12VDC power supply.
Source voltage really doesn't have anything to do with it, outside of the fact that if you don't have a power supply to step up voltages, you will be limited on the output power. The power supply in the amp will step up voltages to meet the requirements of the output devices on the rail. If it's on 120V AC, then it's stepped down and taken to DC to meet the same requirement. It's about the output device topology, not source voltage.

For a basic primer on auto audio electronics, visit here;

Basic Car Audio Electronics
 

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If you knew anything about speakers (and specifically subwoofers) you'd quickly understand that the energy stored in the speaker's equivalent acoustic circuit is so overwhelmingly large that any difference in damping from the amp is almost irrelevant. Take into account the additional ringing from any other resonant component in the enclosure and there's always going to be a "lot" of ringing no matter what the amp is trying to do. That's the point GotFrogs (Andy) was making.
 

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If you knew anything about speakers (and specifically subwoofers) you'd quickly understand that the energy stored in the speaker's equivalent acoustic circuit is so overwhelmingly large that any difference in damping from the amp is almost irrelevant. Take into account the additional ringing from any other resonant component in the enclosure and there's always going to be a "lot" of ringing no matter what the amp is trying to do. That's the point GotFrogs (Andy) was making.
Then you might want to take a serious look at your design then. When at Altec, extensive testing was made in the 24 cubic feet 8182 sub system, (3182 18" 8 ohm driver) and was bundled with the SS 1270 amp specifically due to it's damping performance. I do know a little bit about what I'm saying here.

When you take the position like you have, I can only interpret that to mean, "I cannot control my design, therefore, it's irrelevant."
 

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I e always thought the speaker played a much larger roll then the amp. I doubt there are many amps today that won’t fit the bill.
I had a write up once that showed it not making a difference but I can’t find it. It had measurements.
 

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I e always thought the speaker played a much larger roll then the amp. I doubt there are many amps today that won’t fit the bill.
I had a write up once that showed it not making a difference but I can’t find it. It had measurements.
The anechoic chamber tells no lies. it is what it is.
 

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Source voltage really doesn't have anything to do with it, outside of the fact that if you don't have a power supply to step up voltages, you will be limited on the output power. The power supply in the amp will step up voltages to meet the requirements of the output devices on the rail. If it's on 120V AC, then it's stepped down and taken to DC to meet the same requirement. It's about the output device topology, not source voltage.

For a basic primer on auto audio electronics, visit here;

Basic Car Audio Electronics
Then you might want to take a serious look at your design then. When at Altec, extensive testing was made in the 24 cubic feet 8182 sub system, (3182 18" 8 ohm driver) and was bundled with the SS 1270 amp specifically due to it's damping performance. I do know a little bit about what I'm saying here.

When you take the position like you have, I can only interpret that to mean, "I cannot control my design, therefore, it's irrelevant."
Sorry, I can't help but point out the irony here, as futile as it may be...

Per your "basic primer" Basic Car Audio Electronics link above, section 99, Damping Factor, says: "Some switching amplifiers like Class D amplifiers have a lower damping factor than their Class A/B counterparts because the output of the amplifier has to pass through an inductor. Since the inductor is wound with copper wire which has resistance (albeit a very low resistance), the damping factor is reduced. Generally the lower damping factor is completely inaudible."
 

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Sorry, I can't help but point out the irony here, as futile as it may be...

Per your "basic primer" Basic Car Audio Electronics link above, section 99, Damping Factor, says: "Some switching amplifiers like Class D amplifiers have a lower damping factor than their Class A/B counterparts because the output of the amplifier has to pass through an inductor. Since the inductor is wound with copper wire which has resistance (albeit a very low resistance), the damping factor is reduced. Generally the lower damping factor is completely inaudible."
Class A/B can be rated as high as the thousands, however, you rarely can find this in Class D because of it's design. My Class D is rated >200 @ 4 ohm. It all depends, as I stated before, how the output circuit is designed, and on many Class D amps, this is overlooked or ignored. At low frequency >100 is preferred.

It doesn't provide any irony, what it does, is only to go to show why in usage of Class D, loading an amp @ 2 or 1 ohm will only decrease damping performance into undesirable levels, and at those loads can even make some amps become unstable. It's no different than tube amps based on transformer outputs, however, the valve amps naturally function in quasi Current-drive having a high output impedance with minimal damping. A small amount of negative feedback taken from one speaker terminal is fed back to the cathode of the first input valve. Feedback reduces the output impedance and introduces damping to control excessive Q resonance of the speaker. Valve amps are naturally noisy (hum) and negative feedback quietens the amplifier and marginally reduces measured distortion. Effectively implementing this type of control in Class D is what many designers overlook. It's why Class A/B SS amps shine so well at low frequency damping factor and driver control.

History has been forgotten and there is little interest in reflecting on what was not understood during the transition from valve to solid-state technology in relationship to returning to an inductor in the output design. (the same holds true to low quality inductors in crossovers reducing DF) All that was required was a simple addition to the gain management of solid-state amps to enable Voltage to Current drive adjustment so the DF of speakers could be effectively managed.

So, we are back to the OP's Q, and having said that, it's always better for SQ to utilize 4 or 8 ohm driver load, than to attempt to utilize 2 or even worse 1 ohm loads, especially on Class D. It isn't about maximum power, it's about maximum control.
 

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When it comes to cone control on a subwoofer, a servo will do more than damping factor ever will. Change my mind!
 

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What does that have to do with the OP's Q?
You are the one bringing up damping factor and how it relates to SQ. So... batter up!

EDIT: This thread is also borderline necro status, so does it really matter what my answer has to do with the OP's question?

EDIT2: I'll just leave this here - https://www.butleraudio.com/damping1.php
 

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You are the one bringing up damping factor and how it relates to SQ. So... batter up!

EDIT: This thread is also borderline necro status, so does it really matter what my answer has to do with the OP's question?

EDIT2: I'll just leave this here - https://www.butleraudio.com/damping1.php
Quasi-experts in this forum abounds I see...

Butler's transformer based valve amps can have their own opinions, however, it isn't rational, especially when trying to compare output topology. Educate yourself on DF between topology (voltage vs. current) first.

Valve Amps: Valve verses Solid-state amps

On SS amps, you're right back to what Crown Amp Enginners clearly stated, which I quoted before;

From Crown Audio Amplifier Engineers; "Loudspeakers have a mind of their own. You send them a signal and they add their own twist to it. They keep on vibrating after the signal has stopped, due to inertia. That's called "ringing" or "time smearing." In other words, the speaker produces sound waves that are not part of the original signal. Suppose the incoming signal is a "tight" kick drum with a short attack and decay in its signal envelope. When the kick-drum signal stops, the speaker continues to vibrate. The cone bounces back and forth in its suspension. So that nice, snappy kick drum turns into a boomy throb. Fortunately, a power amplifier can exert control over the loudspeaker and prevent ringing. Damping is the ability of a power amplifier to control loudspeaker motion. It's measured in Damping Factor, which is load impedance divided by amplifier output impedance. High damping factor equals tight bass."

Go argue with the Engineers at Crown... Next?
 

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Quasi-experts in this forum abounds I see...

Butler's transformer based valve amps can have their own opinions, however, it isn't rational, especially when trying to compare output topology. Educate yourself on DF between topology (voltage vs. current) first.

Valve Amps: Valve verses Solid-state amps

On SS amps, you're right back to what Crown Amp Enginners clearly stated, which I quoted before;

From Crown Audio Amplifier Engineers; "Loudspeakers have a mind of their own. You send them a signal and they add their own twist to it. They keep on vibrating after the signal has stopped, due to inertia. That's called "ringing" or "time smearing." In other words, the speaker produces sound waves that are not part of the original signal. Suppose the incoming signal is a "tight" kick drum with a short attack and decay in its signal envelope. When the kick-drum signal stops, the speaker continues to vibrate. The cone bounces back and forth in its suspension. So that nice, snappy kick drum turns into a boomy throb. Fortunately, a power amplifier can exert control over the loudspeaker and prevent ringing. Damping is the ability of a power amplifier to control loudspeaker motion. It's measured in Damping Factor, which is load impedance divided by amplifier output impedance. High damping factor equals tight bass."

Go argue with the Engineers at Crown... Next?
Speaking of Quasi-experts. Isn’t the internet great, you can always find something that agrees with you. And a lot that don’t.
 

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I'll state this... I'd be willing to bet that I could predict the results of someone in an a/b/x listening test where they are subjected to a subwoofer amplifier with a damping factor of 50 and a damping factor of 100. Out of 100 people, 98 of them wouldn't be able to tell which amplifier they were listening to based on damping factor beyond any statistical significance of guessing. The other two outliers may be just that dang good OR that dang lucky. Regardless, chances are anyone reading this thread will be in the 98 people group who won't be able to tell, yet most will think they are the golden ear two without being able to tell yet alone repeat the results.

Now let's take this further with a car amplifier, where the damping factor spec used to be cheated by being measured at the circuit board, versus at the speaker leads, yet alone the speaker itself. Yeah, good luck with that spec making a huge difference in SQ when you don't even know where it is measured.

Back to my original comment when it comes to cone control, a properly designed and implemented servo will beat damping factor 7 days a week and twice on Sunday! It should also reduce subwoofer induced distortion from the cone movement itself. I was told that the Velodyne car audio servo subwoofer was one of the best, but they failed to take one variable into consideration with the cone position sensor.... The movement of the vehicle itself. It was great for an SQ competition, but in some instances, results could vary once the vehicle was in motion. Oddly, this was vehicle dependent as I knew two different people who used this setup and one claimed it was fine with the vehicle still or in motion whereas the other one said it only worked in his trailer queen SQ vehicle and driving made the sub vary...

Which brings me to my next point. We are talking about CAR AUDIO here, which is generally the absolute worst reproduction environment that anyone could ever want when it comes to audio... At least modern day digital processing is making it better for multi-listening positions and imaging, to some degree. Good luck getting your anechoic chamber response in a vehicle.
 
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