What Class D amps will drive a 2 ohm load

Hello George,

     For class D amps that double their output as impedance is halved down to 2 ohms, it looks like all the new Merrill Element amps, also using the new GaN fast switching transistors, all are capable but they're expensive, starting at $15K/pair for the Element 114 mono-block amps:

https://merrillaudio.net/products/

     However, Merrill's previous Veritas monoblocks, came close to doubling power down to 2 ohms at low rated distortion levels:

https://merrillaudio.net/veritas-mono-block-power-amplifier/#1519988773686-7ab00bcd-5607

     I don't know dsper's budget, but I've been considering buying a used pair of these and most are listed at about $5K/pair. I consider a pair of these in good condition the likely best bargain solution. New, the Veritas were priced at $12K/pair.

     The OP, dsper, was inquiring about a class D amp that could handle his speaker's crazy low impedance loads of less than 2 ohms without freaking out.

     Since this new amp from Purifi Audio was born out of the research work of Class-D pioneers Bruno Putzeys (of Philips, Hypex and Kii Audio fame) and Lars Risbo (Toccata Technology and Texas Instruments) and can handle speaker impedance loads under 2 ohms, even if it does so at less than ideal wattage and distortion levels, I thought dsper still might want to give it a try, anyway.  If Purifi offers the typical internet-direct free in-home trial period, there's literally no risk to dsper from giving it a whirl.

Tim  

Our prototypes can double power into 2 ohms and we’re not even trying to make it do that. It comes with the territory.

+10 atmasphere for putting that one to rest.

Nothings been put to rest, let’s see the independant test or even his own, that show the rms wattage doubling just before clipping (same distortion) with all three 8, 4, and 2ohm loads, then I’ll eat my words, and congratulate you on doing something that other Class-D’s can’t. I’ve asked the same from Merrill twice now and got no answer.

And btw, I’ve never claimed the new GaN Technoglogy could drive these speakers properly and double at all 8 to 4 to 2ohms loads either, they just sound better than the old technology, but I wouldn’t recommend them here either.

So dsper find yourself a brute linear amp/s with BJT (bi-polar) output stage, with high bias Class-A used somewhere to get the best from your highly regarded speakers.
Do not get sucked into by these Class-D spruikers because you won’t get the best from your speakers.
Or (I wouldn’t) sell your speakers and get something easier to drive that doesn’t reach down to sub 2ohm loads in the frequency range, then you can by a GaN based Class-D which will sound very good.

Cheers George

and can handle speaker impedance loads under 2 ohms,

dsper That statement it’s should tell you something, they "can handle" a 2ohm load.
My car "can handle" being reved to 8,000 rpm. My hands "can handle" 60c on a Class-A heat sink for a few seconds!

Your speakers are at 1-2ohms for nearly 3 octaves in the bass
"JA which means that the amplifier with which it is used must have ample—to say the least—current capability if the sound is not to become anemic."

Like I said above " find yourself a Krell type ect linear amp/s with BJT (bi-polar) output stage, with high bias Class-A used somewhere to get the best from your highly regarded speakers."

Read these amps that were tried and you’ll get an idea of what’s needed to get the best from your speakers.
.

JA Stereophile.
" The best one I heard was the Krell KSA-250 (their latest product—though by the time you read this there will be a KMA-600), followed not too far in second place by the older Krell KSA-200.
The newly arrived Threshold SA/12 monos had plenty of overall power, but lacked the drive at the low end possessed in such quantity by both Krells, and had a refined, neutral upper range that seemed to leave the Thiels lacking in sparkle.
Until now, my favorite overall amplifier has been the Mark Levinson No.20.5, but it simply didn’t have the low-end punch necessary to bring the CS5 to life"

Cheers George

Nothings been put to rest, let’s see the independant test or even his own, that show the rms wattage doubling just before clipping (same distortion) with all three 8, 4, and 2ohm loads, then I’ll eat my words, and congratulate you on doing something that other Class-D’s can’t. I’ve asked the same from Merrill twice now and got no answer.

And btw, I’ve never claimed the new GaN Technoglogy could drive these speakers properly and double at all 8 to 4 to 2ohms loads either, they just sound better than the old technology, but I wouldn’t recommend them here either.

Its put to rest everywhere but (by your admission above) in your own mind. Although we just got news this week that the USPTO is granting our class D patent with all 20 claims supported, that isn't the same as saying we're ready with a production product that is going to independent review. The power supplies that we are using for testing won't support the current of 2 ohms at full power even though the circuit boards we designed will. But the amp behaves as a pretty good voltage source so as long as you stay within the limits of the power supplies we're using, doubling power into 2 ohms is no worries.

I am well aware you didn't make that claim about GaNFETs but if you apply United States 5th grade reading comprehension skills (which these days isn't saying much) you will see that I suggested that this was something you might not have been aware of and by your admission above that surmise was correct. Again, what I said is that the output impedance of an GaNFET-based class D amp is so low that it will easily double its power into 2 ohms from 4 ohms- provided that the power supplies and heatsinks will allow it. These latter qualifications BTW are the same ones that limit any traditional solid state amps as well, so none of this is any surprise to anyone anywhere, except perhaps you.

Nothings been put to rest, let’s see the independant test or even his own, that show the rms wattage doubling just before clipping (same distortion) with all three 8, 4, and 2ohm loads, then I’ll eat my words, and congratulate you on doing something that other Class-D’s can’t. I’ve asked the same from Merrill twice now and got no answer.

That would be cool. But what non-Class D amps exactly are we comparing these to that have been proven to do the trick?

George sounds like you are convinced accordingly that some existing non-Class D amps are proven to do the deed so tell us which proven amps specifically you are recommending dsper consider buying?

Thanks.