Need at least 900wpc in 4ohm

Suggestions for what can do the job? Thanks.
Parasound JC1 testing from Stereophile:

With continuous drive, the Parasound clipped at 545W into 8 ohms (27.4dBW)¬óway above the specified 400W. ("Clipping" is defined, as usual, as the power level where the measured THD figure reaches 1%, and is shown in fig.7 as the horizontal magenta line.) With a low-duty-cycle 1kHz toneburst more representative of music, the Halo was a powerhouse. Its clipping power increased by 0.3dB into 8 ohms, reaching 586.5W at 1% THD (27.7dBW, fig.7, black trace), with 1154W available into 4 ohms (27.6dBW, blue), 2255W into 2 ohms (27.5W, green), and no less than 4.2kW into 1 ohm (27.2dBW, magenta). The latter is equivalent to an output current of 64.7A!

Sounds fantastic too!
Sanders Stereo Magtech Amplifier:


Sanders Magtech Mono:


Why do you need that kind of power?
Why do we need a car with 350 horsepower? Why do we need a 5 bedroom 3 bath 2 story house for a family of 3?
Because the "bigger must be better" theory of life!

Most people have no clue that an average living room needs only about 2-3 watts of actual power to drive the speakers at 90db sound pressure level. The trick is when there's a peak in the music that needs 100 watts or 500 watts for a millisecond, you won't hear clipping or distortion for that fleeting amount of time when the amp is called on for the reserve power.

This is the reason that the government outlawed specifying home audio amps using peak power. In the old days, if the output was rated at 1,000 watts peak power (maybe for a nanosecond), the actual RMS power output was about 50 watts. Which rating do you think makes better advertising?

BTW, in their infinite wisdom, they forgot to include automotive power amps, so the car amp manufacturers can claim 1,000,000 watts of power without specifying for how long and into what load.

I have a McIntosh MC2500 (500wpc) feeding a pair of Martin Logan Quest hybrid electrostatics to my home theater 9.2 system for that reason. Plenty of reserve.
You can do this cheap (+ runs quietly!)with the Yamaha P7000S:

If you would rather have Class D (runs cool and also runs quietly!):
You could get 2 Crowns and run them in bridged mode if necessary.

Perhaps just a single amp would be enough if you get the largest Yamaha or Crown.
Bridge a pair of Mcintosh Mc 2500 or Mc 2600 amps together. 1 to 1.2KW of power.
Krell 700cx; 1400 Wpc into 4 Ohms.

By the the JC1 won't do that, 800 Wpc perhaps.
Steve -

Per the Stereophile review the JC1s measured:

585W @ 8 Ohms
1154W @ 4 Ohms
2255W @ 2 Ohms
4.2kW @ 1 Ohm

Google it and you can see the tests. Krell is another great choice!
McCormack DNA-750 monoamps--650 into 8 and a kW into 4. $5K per pair (delivered to you, IIRC) from Spearit Sounds. EXCELLENT sound.
This is like saying I need a 500 horsepower car.
Why don't you list the system requiring this?
FWIW the new Mcintosh gear is not the same as the later generations. I've had MC amps since 96 and that gen. was warm. The new amps/pre ie. 352,452,601, and 1.2 are nearly inert in their signatures. Stereotypes, hard to shake, pun intended.
Danielk141 - building system around primo pair of Snell AIII's. After testing six amps on them, they clearly need as much power as you can give them. Issue clearly demonstrated. Not just chasing big numbers....
Amps were: B&K AVR707, Mcintosh MC7000, McIntosh 452, Classe 2300, ARC Ref 150, Bryston 4Bsst2 and Sanders Magtech. Thanks
Gshepard, I definitely want to hear the Snells with a couple of MC 501's or more power. Like to think the 7000 and 452 weren't enough power and 501's would be less "warm". Thanks.
Sunfire 600 should be on the top of your list. It pumps out 1200 watts into 4 ohms and sounds fabulous at all volumes. It's a shame they aren't made anymore, but they come up on ebay regularly.
Make this the third vote for the Sanders Magtech.

It is an extraordinary amplifier with a superior power supply courtesy of its linear voltage regulator.

If more power is needed (and it might be if you are running full range ESL or large planar speakers) then the Sanders Magtech in a mono-bloc format will deliver 2000 watts into 4 ohm. That rating is of course RMS for both channels driven at any audio frequency (20 Hz to 20 KHz) and with a THD level cited in the manual of just 0.01% at any power level below clipping.
I would rather hear the speakers with high quality 100 watts per channel class A monos.
Devilboy, LOL! The Snells do require a commitment! Size of small refrigerators and 150 lbs a piece! But there's a reason they often make the 10 Best Speakers ever list. Certain cult thing as well. The AIII was headed for production release when Peter Snell dropped dead at age 38 (?) in his shop in 1984. A great talent lost to the art and science of audio. Thanks.
am surprised that nobody mentioned Spectron amplifier. Its very powerful as many know or should know. From their web site:

ABSOLUTE POWER by James L. Darby:

"Recently, a friend of mine bought a new car - a Bentley Continental GT.....engine was silent and silky smooth and provided the sensation of taking off in 747... That is how I would describe listening to the Spectrons; quiet and luxurious with no sense of effort at any volume level... More than most other amps, the Spectrons allow you to feel the music (not the sound) as well as hear it... Like the Bentley, you don't think to yourself, "Wow! This is powerful!", you are not conscious of the power at all. You are conscious of the music in all its pristine glory without much of a perception of electronics at all; the music just is...Like the Bentley, the Spectrons excel at speed.."

"[Musicians] also were articulate and listenable at low levels. I cannot explain why, but it is true. More than once while playing at background levels, I was drawn in to the music to the point I had to sit down and listen..."

It has enormous headroom i.e. reserve power for crescendos which only a few class A amplifiers have and only Mark Levinson No.53 (at $50k) is another class D amp comparable in that regard.

However, you need not only power but...FINESSE and Spectron which has "Best Sound at CES" Award is one of the best amplifiers I know and tried. My speakers, "Sasha "are most power hungry among Wilson speakers and I am extremely pleased with Spectron I have not only in power but in sheer musicality. I would use word "seductive" describing its sound. Of course good preamp will help too (I have Joule-Electra "450ME").

At $3,995 a piece its not a brainer, I would think!

I agree with the Tccaux, Snell AIII was one of the best speakers of its time and still may be.
Friends that had them used big Threshold amps.If they can be found that's the amp for these speakers
Sorry about the misinformation on the JC1s, they do perform indeed! Plus, they sound great.
The more I'm thinking about this, the more I think it's absurd that a speaker needs 900 watts to sound good. Are you saying you have a speaker that needs 900 watts for the entire speaker, or just bass drivers? I'm not doubting the sound quality a snell is capable of producing, but my common sense says that a driver/speaker requiring 900 watts to convey an emotional connection to music simply hasn't been designed properly.
Remember the impedance, most us don't know what size room the OP has. There are other very fine speakers that work best with an abundance of available power too. Furthermore, there are a lot amplifiers available to choose from that can fulfill the demand. The final result is what matters.
Devilboy, I agree that my subject line is over simplified. A more accurate assessment would be at least 500wpc with ability to deliver more. The 900 watt in 4 ohm Magtech is what set the standard for preferred performance. To Unsound's point, the room is large and open with pitched, vaulted ceiling. Thanks
I would suggest what you need speakers. High sensitivity speakers make low sensitivity speaks sound like they have a wet blanket over them.
High sensitivity speakers make low sensitivity speaks sound like they have a wet blanket over them.

Until you feed them with 900 Watts. :)
I love Triode's AND Jim_swantko's comments. I've tried both, having had several different SET amps in my systems the last maybe-10 years, driving hi-efficiency (more than 100dB) linearrays. As the rest of my system increased in resolution, so I wanted higher-rez speakers. I quickly determined that I had neither the skills not determination to build them myself, and bought a pair of Audio Physic Avanti IIIs which were fairly quickly succeeded by the best speakers systems I've EVER hear, Vandersteen 5As.

I tried biamping them with a few different combinations of small amps but finally bought a pair of McCormack DNA-750s. WOW did my system 'come to life'. Altho I do not listen at high levels, these HIGH-power amps brought a sense of ease...effortlessness...that my system never had. Tccaux, I suggest you read Peter Moncrieff's review of the DNA-500... get some sense of the McCormack sounds and then understand that the '750 is a further refinement (by the manufacturer, conrad-johnson) of the 2 significant principles Steve McCormack used--Distributed Node Amplification (meaning placing significant powersupply capacitance immediately adjacent to the output transistor) and fully push-pull, differential amplification (meaning that half the amp is pushing while the other half is pulling), and then buy a pair. I'm confident you will NOT be disappointed.
The Snell AIII was a good speaker in its day. It was about the only thing out there that competed with the Fulton Premiere systems. But that was 1984. Snell made a speaker call the B that I found preferable to the AIII- easier to drive and more detailed (still went to 22Hz).

Since the time of the B, there have been a lot of other speakers that have appeared that are easy contenders. If you want something on the scale of a speaker like that, with a reasonable price that is also easy to drive, check out the Audiokinesis Dreammaker, which got a Golden Ear award a few years back. I would take if over a set of AIIIs in a heartbeat- especially if you have a larger room- you need the efficiency.

The reason you need the efficiency is the simple fact that there are no particularly musical amplifiers that also have power in excess of 500 watts. Sure, there is lots of stuff that sounds like good HiFi, but if you want it to sound like real music, that amp does not exist in those power levels, tube or transistor. So you have to get the efficiency going. You might also consider that fact that if you really push a +500 watt amp into those Snells, you will toast them but before that they will be highly compressed.

Sorry to break it to you this way but there is no way to change the laws of physics. If you go with a smaller room you will have a lot more option with that speaker. Of course, if you only plan to play at lower volume levels maybe you will be OK. Personal preference *does* play a role in that regard.
I disagree with Atmasphere's assertion that there are no particularly musical amplifiers that provide in excess of 500 Watts into a given speaker.
Try a pair of Cary 500 MB; 1,000 watts into 4 ohms. They will drive just about anything and not break a sweat... Closest thing to a high powered tube amp that I have heard... They sound great, smooth, and very dynamic. They are excellent mono-blocks for tough load speakers or speakers that demand lots of current (like Maggies). Can pick up a used set for around $4k.
I disagree with Atmasphere's assertion that there are no particularly musical amplifiers that provide in excess of 500 Watts into a given speaker.

Me too. I would also like to see the complete list of >500wpc he has actually heard and compare it to the complete list of all 500wpc amplifiers ever made. And why 500wpc is a magic number where everything over that is not musical. Just silly.
What's silly is a speaker which needs >500wpc. Steve Deckert has a slogan, "if the first watt sucks, why continue?"
Ddd1, 500 watts is by no means the magical number. In fact the common 'wisdom' in this regard is 60 watts. That is to say, most amplifier topologies go downhill if the topology is built to be able to produce more than 60 watts or so.

Now most of you know that I am a tube advocate, but what you may not know is that I don't think tubes are the final answer, just that it is much easier to get them to sound like music. I've been designing and building amplifiers since the mid 1970's and I have built many transistor amps and serviced hundreds if not thousands (I used to run an audio repair operation).

So you may not agree, but you will understand when I say that I don't take most transistor amps seriously, particularly the high power ones. The best transistor amp I have heard was zero feedback, class A and made 100 watts, costing $100,000. It was made by Ridley Audio in Atlanta. It was so smooth and detailed it put most tube amps to shame, let alone all transistor amps.

Transistor amps that need not apply will be class AB and use negative feedback. I'm not quite like Julian Hirsch in saying that these amps will sound pretty much the same; there are variances depending on the power supplies, whether its bipolar or MOSFET, but in general such amps make trace amounts of odd ordered harmonic distortion which causes them to sound bright and take on a harsher character than is natural. Essentially I consider them to have a coloration, and an unpleasant one at that.

So for me the field is thus limited to tube power if we are talking 500 watts. I can count on one hand with fingers left over the number of tube amps that are contenders. Its unfortunate but that is the way it is.
Thanks for the explanation Atmasphere. Maybe this weekend if I have time I'll put my 25wpc single ended SAR Labs Little Wally monoblocks back in and check them out. Switched over to something greener for the purpose of saving money (+ higher power output and balanced inputs) since I like to leave amps on 24/7 but I guess I should put my old amps back in and see if maybe I'm missing something.
Atmasphere to this day I consider the sounds I've heard emanating from Thiel CS 5's in appropriate rooms with their 2 Ohm load amongst the finest I've ever heard. Now, I didn't actually measure the output of the various amps that were being used on them as they were playing, but I'm confident that sound that came from the higher powered ss amps sounded better in part due to that extra power, and furthermore I think it quite possible that in these large rooms that there were times that those speakers might have been drawing 500+ Watts. You can't convince me that what I heard wasn't musical. I suspect that there might be other Audigoners with similar experiences. Perhaps some Apogee aficionados would care to chime in?