What Class D amps will drive a 2 ohm load

I have no idea how they sound but according to Anthem their M1 Class D Monoblocks if connected by 240 volt will drive into an open circuit or short circuit. 

• Flat frequency response into any load, without having to resort to digital conversion or equalization to compensate.
• Stable into all loads including open circuit and short circuit.

According to this the M1s are manufactured by Paradigm -   http://www.theabsolutesound.com/articles/anthem-statement-m1/?page=4

This is the OP again...it sounds like I am hearing Class D might not be the best for tough, low impedance load speakers.

If that is indeed the case, why is this and what has to change in Class D design to achieve it?

The Mosfet output transistors themselves as well as the output filter, which both have not changed much since it’s inception.
The GaN output transistors are maybe going to change that with optional far higher optional switching speed available, so then output filter can also be far higher up, then there’s also no phase shift down into the audio band. But this also needs small heat sinks to be used, as you can see below.
But only one amp so far has utilized that combo this the unobtainable Technics $30K SE-R1 power amp.

https://i.pinimg.com/originals/15/3c/fd/153cfd69d01a6ce16656dedab64f1519.jpg

https://www.technics.com/us/products/r1/se-r1.html

Cheers George

George,
You are not even addressing his statement. Class D can already drive low impedances.......1100 watts from the NC1200 and 1000 watts from the mono 1200AS1 (all at 2 ohms). Tons of high end manufacturers use class d in their subs and in their powered speakers. Certainly, there are those very very few super low impedance speakers that need a welding amp to drive them.

The switching speed of an amp and the type of output devices have little to do with power (so why are you bringing it up?). The Technics does not have super low impedance driving capability (300 watts a channel into 4 ohms and no mention of lower impedance capabilities). That amp converts all analog signals to 24/192 and then fools around with the signal in the digital domain before it changes PCM to PWM.....really a digital amp.

I was talking to someone at IcePower some time ago about them using GaN transistors. They said the engineers were looking at them because they are so efficient they can be used in serious high power amps with less heatsinking. The IceEdge chipset is capable of producing up to 7000 Watts. Imagine what that amp could drive! There is no reason class D cannot drive even super low impedances....but why? Since the number of amps that need drive below 2 ohms is super limited....they why would a manufacture bother? You need higher voltage rails, more capacitors, more output devices, larger circuit boards, more cost, etc. Also......all amps create more distortion as the impedance lowers......I have never seen a measurement of an amp that did not measure worse at 4 ohms compared to 8......and then 2 ohms is even worse. Why would you want to listen to more distortion? High efficiency speakers and reasonable impedances make sense.

BTW, this (link below) has been available for years. No one has made a serious version, that I know of.....2000 watts into 2 ohms.....is that enough power?! It has built in op amp, somewhat low gain and low input impedance.....so probably would never sound as good as the NC1200 tweaked to the max........but, shows what can be done. Look at the size of that 3000 watt switching supply you use with it   Much more can be done with GaNs as they are so efficient.
https://www.hypex.nl/product/nc2k-oem/79

The Mosfet output transistors themselves as well as the output filter, which both have not changed much since it’s inception.
The GaN output transistors are maybe going to change that with optional far higher optional switching speed available, so then output filter can also be far higher up, then there’s also no phase shift down into the audio band. But this also needs small heat sinks to be used, as you can see below.

This statement is 100% and certifiably false.

George, I suggest you read the white papers of Bruno Putzeys. Advisory: its is helpful to know a bit of calculus to follow along.


Your statement about the filter is incorrect if the amplifier is self-oscillating; even if the filter frequency is fairly low (80KHz for example) the feedback used in almost any self-oscillating class D amp allows it to correct the phase shift from the filter from affecting the audio passband.

You don't use GaN devices to increase the switching speed- it appears that Technics did it purely for bragging rights, not sonic merit. You use GaN Devices for their properties such as fast switching speeds, gate input capacitance, output capacitance and possibly lower deadtime. 600KHz is a very practical upper limit for switching with them, not because they can't go faster but because creating a low noise layout gets exponentially harder as frequency is increased. But you should be advised that MOSFET devices have been fast enough for a while that Technics could be easily using them at the same switching speed; Bruno is using MOSFETs rather than GaN devices in his Purefi circuits- think about that for a moment will you? Bruno is arguably the acknowledged master in the world of class D and he's not using GaNFETs. This is not to say that he doesn't acknowledge their benefits. Quite simply it just isn't as you've portrayed it above.