Recently bought a Crest CA-6 for home subwoofer duties. Rated 1500W @ 4 ohms bridged. That can draw nearly 15 amps from the outlet momentarily. Much of that rating is only momentary, depending on capacitor storage. At the "pro" level, seems that most most bass players prefer heavier A/B or H class amps to lightweight class D amps at similar ratings. There are exceptions like the Crown K1/K2 which have linear power supplies but have that "sleep mode" modification for home use. Seen some new class D pro amps rated at 10,000W, however, maybe not into 2 ohms.
SMPS/PWM amps have also, historically, had the issue of repairabilty because of so much integration and timing in the circuits. Can't just replace a component without dramatically affecting others.
Crest CA series has .775V input sensitivity. Can you live with a fan?
Is there such a thing as an amp that does not do better above 2 ohm? Granted some will do way better than others in that case. If given a choice, its probably best to avoid speakers that could effectively measure 2 ohms at all.
Bel Canto Ref 1000M is not rated below 2 ohm impedances. And they do better with higher impedances, 4 or above, for the least distortion. The online Stereophile review with John Atkinson's follow up tests will show the specs and test results. This cannot be extrapolated to other Class D designs, of course. They are fabulous amps though with the right speakers.
BTW, in EE or signal processing,terminology as I understand it (as opposed to digital computing), my references to "bandwidth" above would probably be more accurately termed "dynamic headroom".
BEst case scenario for the D-Sonics might be similar to what I observe with my mere 500w/ch rated BCs, ie it sucks the power from the line when you turn it on without issue then is powered up and ready to go with relative little strain on the external power line from there.
So it sounds like there are grounds for cautious optimism.
One point to note, in relation to AC current requirements: Although the subject line of the thread refers to 1000WPC, the amplifier in question is a monoblock rated at 1500W.
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.
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).
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.
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!
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.
. The Carver monoblocs are rated at 575 wpc @ 8 ohms and 900 wpc @ 4 ohms. I am using two monoblocs per speaker to drive the Kappa 9. One monobloc per speaker just doesn't get optimal results. .
I doubt power ratings for any switching amp is "sustained", but not sure exactly how to quantify it. Al could probably do it better or maybe agoner Kijanki if he is out there (both excellent EEs).
I have heard mixed reviews with Class D amps on very difficult load speakers like the Infinity's seem to be. The devil would be in the details I suppose. My OHMs are not easy, but I suspect not as difficult either. I might go out on a limb though and say that if the Carver amps can handle it, a good Class D design with a good power supply design (not stock Icepower for example) probably would do fairly well. Again, devil in the details.
I had a 360 w/ch Carver m4.0t amp for years before recent upgrades, two amps ago, running older, larger Maggies and my OHMs. Bass WAS wall shaking prodigious on the OHMs with proper recordings, well recorded organ music, etc. Bass with my Bel Canto Ref1000m is equally impressive, but night and day, way more clean, powerful, and nuanced, though I seldom get the wall shaking effects that the old Carver gear (amp and pre-amp) used to provide. I think it has more to do with the low end rolloff of my ARC sp16 tube pre-amp compared to the old Carver pre-amp than with the amps though.
. Map, I've never tried a class D amp before. The whole concept of small amps delivering that kind of power is intriguing to me. I have Carver Silver 9t monoblocs that do an excellent job in a biamp config on the Kappa 9. They weigh only 13 pounds each...the Pass monoblocs weight more than 130 lbs each. The Carvers actually deliver bass with much more authority than the Pass monoblocs. But, the Carver amps are 20-25 years old. I need to get rid of them before they go bad. I'm looking for some 21st century amplification and to save some money. If this class D stuff is all it's cracked up to be, there's nothing more than I'd like better to do than get rid of all this "Big Iron" and go small and efficient.
Ddd1...Hmm, no mention on the D-Sonic site on whether the 1500 wpc is sustained or for milliseconds. That really changes the picture if it's only for milliseconds.
Al...I will make inquiries directly to D-Sonic and do some research as you have suggested. D-Sonic has a 21-day trial with a 10% restocking fee.
Mitch, there isn't much information provided about those amplifiers at the D-Sonic site. If you haven't already done so, I would suggest that you research and/or try to confirm with the manufacturer that they can handle the extremely low impedance of the Kappa 9.
The Kappa 9s, when used with their "extended/normal" switch in the "extended" position (which iirc seemed to be the most commonly preferred setting), go down below 0.8 ohms at multiple bass frequencies, where lots of energy is typically required. The "normal" mode is not quite as severe, but is still very challenging.
Also, I don't know what their phase angle behavior is in the bass region, but it wouldn't surprise me if it was significantly capacitive, adding to the severity of the load.
My impression is that the impedance characteristics of the Kappa 9s, rather than their inefficiency, are the main reason for their reputation as amp killers, although both factors undoubtedly contribute.
. I own the notoriously inefficient Infinity Kappa 9 speakers. They are known for bringing amplifiers to their knees. They need to be biamped to be their best. It takes a lot of power to wake them up. I'm thinking of throwing one or two pairs of the D-Sonic 1500 wpc monoblocs at them. .
Another way to look at it: think about the power/energy that goes INTO making music, be it acoustic, electronic, symphonic, big band, rock, rap, jazz, whatever. Then it becomes clear why one might want a lot of it similarly to play back a recording, especially for certain types of music.
Bruce (Bifwynne), note that the OP's listening room is a HUGE loft. Also, keep in mind the rule of thumb that for the volume level to be subjectively perceived as "twice as loud," ten times as much power is required. So 1500W would be subjectively perceived as only "twice as loud" as 150W.
"Who the he*l would want or need that much power and for what purpose???"
Bi, with the right speakers that can use it, you'd be surprised! Especially for lifelike volumes and dynamics with large, lower efficiency, full range speakers in larger rooms.
500w/ch with my big OHM F5's in one of my larger rooms is a godsend! The amp is no longer a bottleneck in any way for my listening enjoyment. Even my small Dynaudio monitors in my small 12X12 office benefit. I will likely never go back to less, unless someday I jump ship to the high efficiency speaker/tube amp camp, which is not likely.
And with CLass D amplification, all that power and dynamic headroom comes in two little boxes about the size and weight of a Webster's home dictionary! Amazing!
Who the he*l would want or need that much power and for what purpose??? Is the OP thinking about using his 1000 wpc amps to heat the house or light up outdoor X-mass lights. I gotta believe that even with inefficient speakers, with that much power, even on transients, pumping out of those amps, the OP would blow his ears.
My 500 w/ch BEl Canto ref1000m Class D amps are on a regular home circuit. The only time they trip the breaker is if I power them both up at the same time. That does it every time! They have never tripped the breaker while playing, and I go pretty loud sometimes. Prior Class A/B amps I've had would trip the breaker on occasion while playing loud.
The switching nature and resulting efficiency of Class D amps is the key I believe. They are much easier for a normal person to deal with than giant heavy Class A or Class a/b type amps. That's progress....
Can an amp pull 1500 WPC from a regular household wall socket?
Not for very long, without tripping the breaker. However, it may not have to.
1500 watts per channel is a total output of 3000 watts. Assuming the amp is 95% efficient, which may be optimistic, it would draw 3000/0.95 = 3158 watts from the wall outlet to provide 1500 WPC. 3158 watts at 120 volts is 26.3 amps.
That would trip the breaker if drawn for a significant amount of time. Also, if it is drawn just occasionally, on musical peaks that are brief enough to not trip the breaker, it would probably cause the line voltage at those instants to drop by a few volts or so, depending on the length of the wiring between the outlet and the breaker panel. That voltage fluctuation might have audible consequences in some or many systems.
On the other hand, depending on speaker efficiency, listening volume, the dynamic range of the music you are listening to, and other variables, you may not actually utilize a lot of the power capability of the amp, which would reduce the amount of current that it draws from the wall outlet correspondingly.
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