Can You Get 1,000 WPC Out Of Regular Wall Socket?

I see in this review of the M2-1500M a statement by D-Sonic's owner/designer that "all of our amplifiers perform per specification into sub 2-ohm impedances." That does NOT seem to me to be an encouraging sign with respect to its compatibility with the Kappa 9.

On the question of how long the rated power can be sustained, assuming that the provider of the rating is not being devious it would have to be for far longer than milliseconds, in order to comply with Federal Trade Commission requirements for amplifier power ratings. My understanding, though, is that in general Class D amplifiers cannot sustain their rated power for as long as other amplifier classes typically can. Kijanki is more knowledgeable about Class D than I am, so hopefully he will see this and chime in.

Regards,
-- Al

My recollection is D-sonic mainly packages stock Class D amps from other companies. Older D-sonic amps are stock Icepower....not as robust surely for such a demanding application. The newer D-Sonics use a different provider of stock Class D amps (is the name known or confirmed yet?) that appear to be a newer generation of Class D amps targeted for commercial applications mainly, outside of D-sonic that is packaging and marketing it for home use, that appear to be a beefier design than older stock Icepower. With their huge power ratings and seemingly decent stock power supply design and current delivery capability, they just might have a good chance of cutting it with even the most demanding speakers out there perhaps, like the Infinity's. I'm thinking it would be worth a try unless some hard reason not to were to come up. I'm definitley curious to see how it would work out. The one caveat I can think of is that commercial speakers that these newer Class D amps are used in tend to be more efficient and easy to drive designs, which is important for commercial applications. But they just might have enough guts to drive most anything in a typical home application. Very interesting! Class D is definitely a place where things are still happening and evolving these days!

Al, I found this long time ago searching for power test of 200ASC (Icepower module used in my Rowland 102):

"I operated a sample 1000ASP on the bench delivering 350W average of pink noise into a 4 ohm load for over one hour with no additional heatsink and the metal case stayed below 55°C.

However, higher levels would make the power supply voltage go down to act as a thermal compensation. Much nicer than just shutting down.

However, with 1214W of sine wave, partly into clipping, after about 35 seconds, the output level would drop to about 600W by the protection circuitry. Remember this is with no additional heatsink.

The 200ASC, I was able to operate with sine wave at 100W into 4 ohms continuously. Turning it up, with sine wave, the module would shut down at about 214W.

However, with pink noise at 100Waverage and a 6 db crest factor, the 200ASC would run all day without shut down, until I was tired of tying up one of my Audio Precisions with it. It would also run all day with music, driven hard where the output limiter was set to a peak limit of 210W maximum. That is, the limiter would allow small amounts of clipping. Driven so the limit light in our external optical limiter was on essentially continuously."

It was posted in February 2005 on diyaudio.com forum. Normally 1000ASP is attached to some external heatsinks and should perform better. 200ASC module doesn't have this option.

Music has very low average power - just few percent of peak power. It is not only because of gaps but also because average half loudness is equivalent to 1/10 of power. I would expect long term average power for this 1kW amp to be much less than 100W but it depends on the type of music. Jazz has very low average value but it is much higher for heavy orchestral pieces. Module has 80% efficiency. Assuming two channels at 1kW, supply power is 2x1kW/0.8=2.5kW. It will require 21.7A and 20A circuit breaker should not trip since orchestra forte doesn't last forever. It would be better to put each monoblock on separate breaker or even better - separate phase of 115V.

Class D have also power bandwidth limitations (to protect output filter) but it is way above tweeter's max power. Datasheet for 1000ASP shows 1kW up to 4kHz dropping to 200W at 10kHz. We don't need to worry about it. FTC power, that you mentioned, is shown for 1000ASP as only 150W, but Icepower specifications are very conservative and it is measured without external heatsinks. With 200ASC module FTC power is 55W, but test proved continuous operation at 100W.

Mapman, thank you for kind word. 1000ASP is 58% louder than 200ASC since power ratio is k=5 while

Perceived loudness = k^(1/3.5) = 1.58

It doesn't look that much of a difference but the key is in max current delivery. It is 40A for 1000ASP and only 12.5A for 200ASC. Perhaps because of that minimum load for 100ASP is rated 2ohm but for 200ASC it is 3ohm. I don't have problem with that since my speaker dips only to 3.6ohm (nominal 6 ohm). As I mentioned Icpower spects are very conservative. Muralman1 runs H2O amp based on 500W Icepower module (rated for 2 ohm min) driving 1ohm nominal impedance Scintilla planar speakers with great sound and without any problems.

Maximum output current chart for 1000ASP shows 40A for 0.35s, 30A for 3s, 22A for 45s.

It is also worth mentioning that many Icepower amps (including 1000ASP and 200ASC) have switching power supplies. Main benefit of that is regulated supply voltage that is steady under changing load or dropping supply voltage (line and load regulation). Jeff Rowland strongly believes in switching power supplies. His newest class AB amps have switching power supplies operating at 1MHz (amazing).

Kijanki delivers! Thank you sir!

I also recall adiogoner chadeffect driving large Apogees with great success using BEl Canto ref1000 or ref1000m. 1000m is better built for the job. That tells me that these amps are up to most any job. I know they are in my application with large OHM 5 series 3 and Dynaudio Contour 1.3mkII, both of which are known to thrive (to different degrees somewhat perhaps given the size difference) on lots of power, current and bandwidth. I have yet to see tehm even come close to "breaking a sweat". They always run cool and seem to have the ultimate bandwidth for home audio.

That is a very good omen for Class D and Infinity. Better Icepower implementations like Kijanki's Rowlands or my BCs are probably a safe bet, though somewhat pricey as Class D goes. Wyred might be another at lower price point. D-Sonics are too new to know for sure I would say at this point but may have potential to push the CLass D value proposition even further.

GIven the inherent potential benefits for my application, I went for broke (with my budget) with the BC ref1000m amps and do not regret it. They still sound as darn near perfection as pretty much anything I have heard over the years. Rowland and Spectron were two others I considered when in "go for broke" mode. BTW, I strongly considered the large Pass amps as well but really had no desire in the end to go with something as big, heavy and power consuming as those, though I am certain they woudl have sounded fantastic, and I love the looks as well.