What Class D amps will drive a 2 ohm load

Our preamps can drive such low input impedances-

Of course it can, how did I know that was coming, stick with tubes, your good at it, and built your rep on them.


The fact is this amp without buffer it has around 15db of gain around the same as the Nelson Pass First Watt F5 and with today’s high output sources and preamps, in most cases you don’t need another soul destroying opamp buffer in the signal path with or without gain.

Here is the comments from a manufacturer of these Purifi’s Class-D amps when I queried him on the unnecessary low 2.2k input impedance. I think it could be because of the use of bjt input stage instead of fet, I’ve yet to suss that one out.

Yes you are absolutely correct that you can use a high output DAC directly into this module. "That would be the ultimate solution"
And I am considering a buffer bypass mode. However most power amps will have gain in the region of 26dB to account for sources down to 2 Vrms. A typical DAC straight in is a good solution with digital volume

Most digital sources today have far more than 2v and owners preamps can certainly have enough for the Purifi without another buffer.
As Nelson Pass with his F5 said " If you need to turn the gain up on your preamp, then do so."

Cheers George

Here is the comments from a manufacturer of these Purifi’s Class-D amps when I queried him on the unnecessary low 2.2k input impedance. I think it could be because of the use of bjt input stage instead of fet, I’ve yet to suss that one out.

Yes you are absolutely correct that you can use a high output DAC directly into this module. "That would be the ultimate solution"
And I am considering a buffer bypass mode. However most power amps will have gain in the region of 26dB to account for sources down to 2 Vrms. A typical DAC straight in is a good solution with digital volume

I explained why already. This is a common issue and why you see many Class D amps with some sort of buffer input. Many opamps can drive lower impedances like 600 ohms no worries and since so much feedback (+30dB) is being used, the assumption is that the distortion added by the feedback on the opamp will be quite minimal. But there are some class D amps where the designer opted to simply have a low impedance input for the very simple reason of having less circuitry- a purist approach. But you have to have a source that can drive it. Its nothing to do with FETs or BJTs.

Whatever Ralph.
Seems like this could be the module your using, as you've turned up the force shields a notch higher on this one, if so just go with the buffer by-pass switch. 

I've mentioned before, we're not using anyone's modules.

It seems that what you aren't getting is that comparitors (a kind of chip or circuit used in many class D amps) can be unstable if used with high input impedances. To prevent oscillation, lower impedances are used at their inputs.

Holy crap - 49 amps. Didn't know this one existed

https://www.hypex.nl/product/nc2k-oem/79

Here's Apollon's version:  https://www.apollonaudio.com/hypex-nc2k-monoblock-amplifier-apollon-audio-nc2kslm/

Yes, 2,000W in 2 ohms. Tell that to some who believe that say a 100W/200W/400W in 8/4/2 ohms amplifier would be more suited to drive 2 ohms speakers just because they double power as impedance halves...