Aleph 3 , Alehp-X

in fact all of the things that must be watched (concerning power into different loads) when building an Aleph also have to be watched when building an X.

In both you can set 3 things:

1. Power Supply Voltage
2. Bias
3. Ac-Current-Gain

With these you can make everything you want (as long as your heatsinks are big enough). For the same power output even the dissipation will be equal between X and Aleph.

I'm always amused and amazed by how these rumors get started. Either the Aleph or the Aleph-X will do just fine with low-Z loads, assuming sufficient bias.
When I first started the original thread on the Mini-A, just about the first thing people asked was whether it would handle a 4 ohm load. In that case, no, I had not provided enough bias for 4 ohms, although increasing the bias is a pretty simple operation. So when I did the Aleph-X I made sure to boost the current so that it would (almost) handle 4 ohms. If you want more bias still, have at it. Just make sure that you have a robust power supply.

i was just speculating, thats all...

as i recall (which could be incorrect), you can make an alephx that can be well suited for 4 ohm loads, but it would be HIGHLY inefficient and produce massive amounts of heat and have a very robust power supply. i just remember its better suited with 8 ohm loads.

just about any amp can be customized to work at different load ratings, some are just more suited for different applications.

im glad you are amused.
Any amp biased heavily enough for a low-Z load is going to be less efficient, regardless of topology, gain devices, etc. The lower the load impedance, the higher the bias required, and the greater the heat generated at idle. If it's not used to produce sound, it goes up as heat, making the amp inefficient. You can't beat physics. All you can do is back off and go class AB or D or something, but then you're changing the rules of the game.