What Class D amps will drive a 2 ohm load


Just asking.

I see specs into 4 ohms but nothing into difficult speaker loads (like Thiel CS5's).

Thanks for listening, 

Dsper


dsper
Rhetorical question: which hypothetical amplifier has more power to drive 2 ohms speakers?

Amplifier A:
100W at 8 ohms
200W at 4 ohms
400W at 2 ohms

Amplifier B:
400W at 8 ohms
700W at 4 ohms
550W at 2 ohms

Amplifier A doubles power for each half impedance.
Amplifier B has more power at 2 ohms.

Just because A is voltage limited at higher impedances, does not mean it supplies more current at 2 ohms than amplifier B.

I would (and actually did) choose to buy amplifier B.
I would (and actually did) choose to buy amplifier B.


Good quality sound? into hard speaker loads it’s all about current.

If you wanted the "best sound (not volume)" into speakers that dip to below 2ohm for most of the bass, then you chose poorly, A would be better sounding overhaul "to a given volume level".
http://3844s14.tracigardner.com/wp-content/uploads/2014/03/youchosewisely.jpg

But if your a head banger and needed volume level, then you chose right in B.

But if the volume of B was as the "same volume" as A, it would not be as good so you chose poorly
https://waserpa.com/wp-content/uploads/2016/05/He-chose-poorly-2-1.jpg

Cheers George

Cascadesphil, thanks for taking the time and sharing your experience. Especially pertanent to me was your description of the amounts of heat being emitted. Well done. 
I’m by no means an expert and cannot speak to class d amps, but old school heavy duty class a amps are made for this sort of load. I drive my Apogees with a Balanced Audio Technology VK-600 with bat pack and couldn’t be happier. Yes, they run hotter than class d (and aren’t nearly as efficient), but everything is a compromise in one way or another. At the end of the day, the quality of the sound and the experience are most important to me.
FWIW,

I went to the Purifi Audio website and found many charts and specifications for their 1ET400A, most of which I did not understand so I could have very well missed something important about relationships between the stats they quoted.

I did see this:
Output Power, Short Term
8ohm, 1% distortion = 227 watts
4ohm, 1% distortion = 450 watts
2ohm, 1% distortion = 450 watts with a footnote stating "Power is limited by overcurrent protection system (OCP) and highly dependent on thermal conditions."

Not sure what the footnote means. 

I went to the Spectron website for the Musician III Mk2 and they tell us "The current headroom is primarily limited by the amplifier’s ability to deliver high currents into low impedance loads. There are many well regarded speakers whose impedance dips down, some even lower than 1 ohm. When a musical note is played at frequencies where the impedance dips, the current demands skyrocket. When this happens with amplifiers that do not have large output current capability, they “current clip”. These transients will be both attenuated and quite distorted. Moreover, most other amplifiers only deliver their rated peak current for sometimes a fraction of the time called for by the music. Spectron amplifiers can deliver peak currents of 65 amps, with a staggering peak power of 3500 watts per channel for over 500 msec (!), which allows the amplifier to deliver the full transient (burst of music) without current or voltage “clipping”. ".

Their stats also state 0.3% THD up to 600 watts in 8 ohms. Could not find anything about distortion at 4 or 2 ohms.

Not sure what that does or does not tell us.

It appears the old adage about trying it in your listening room will tell the real story.

In the meantime, quit bashing my low impedance speakers as they sound wonderful to me in my listening room 😍!

Thanks for listening,

Dsper