What Class D amps will drive a 2 ohm load

Fello A-Goners,

The Class D SX-1000 amps arrived today.

First impression is this...
I'm definitely blown away at the size of these mono block amps!
They're tiny compared to my Phase Linear 700's in size and weight.
Even my wife said WHAT!

I go into this without ANY preconceived thoughts.
I'm an open minded individual.

Tomorrow will be hook up time, to do an evaluation, on these Class D amp's ability to drive some ridiculous low impedance speakers...
Infinity Kappa 9's.

We'll be able to put this discussion to a real world evaluation rather than what my brother's smother's friend of the family said!

Stay tuned y'all...............

Damn georgehifi,

Didn't think there was ANY SPEAKER harder to drive than the 9's.... WOW!
I know the Scintillas were close but DANG!

Something I've noticed with hard to drive speakers.
Given the right amplification they just seem to be more powerful at music reproduction than the high efficiency speakers.
Especially in the bass region.

Didn’t think there was ANY SPEAKER harder to drive than the 9’s.... WOW!
I know the Scintillas were close but DANG!

You can add the OP’s Thiel CS5 also CS7, Wilson Alexia to that list also and there are many others.

And to me also the "good" ridiculously hard to drive speakers are more extended, tighter more detailed in their presentation, this is usually because of the drivers used are inefficient more so the very complex xovers that are designed to be nearer perfect for these types of speakers create the low impedance loads .

There’s no free lunch, easy to drive, simple xovers, efficient drivers, even the use of horns usually have compromises, the above difficult to drive speakers some may say are over engineered, so is a Buggati Veyron ect ect.

Cheers George

Here is a great post by a member here with Sonus Fabers that dip to 2ohms in loading presented to the amp, and his experience with a few different amps and one that can double down wattage all the way to 2ohms the bjt output Gryphon.

https://forum.audiogon.com/discussions/i-listened-to-the-gryphon-diablo-today-what-an-experience/pos...

Cheers George

When some of the "impedance" number were being thrown around in this thread (i.e. < 1 ohm), I was not paying enough attention to realize that figure was for EPDR, equivalent peak dissipation resistance. This is a figure that calculates the peak power loading on the output devices in a linear amplifier when current/voltage are not in phase, it is Not the impedance or a measure of peak current.


EPDR does not apply to a Class-D amplifier. It effectively has no merit in the discussion of a Class-D amplifier. For a Class-D amplifier, the impedance curve is sufficient. Even from a power dissipation standpoint, in a Class-D amplifier, the FETs are not operated in the linear region, so you don’t have the same device loading.