You don't need close to 200wpc

BlueFox

heiney9 wrote: »

You're full of crap, get a clue.

Okay. That sounds reasonable. :rolleyes:

mantis

Amp power I believe is just man hood getting in the way. Everyone wants to walk around saying" I got 500 watts of head beating power" Wolf wolf , what ever.

I do a lot of whole house music systems and most of the time I get this done with either 30 or 60 watts per channel. When I do outdoor speakers I like to be in the 60 watt range or if it's a huge outdoor area I like 120 watts.

In theater rooms Most of the time we are 140 watts or under and for rooms 20 by 30 still work just fine with efficient speakers. Quality of quantity goes along way.

For our 2 channel systems most of the time 60 watts really gets most speakers going very well, controls the bass well etc etc etc. Cambridge and NAD make awesome Intergraded that sing with very nice speakers.
Yes we use Krell and Bryston 300 + watt amps but only on extremely hard to drive speakers. Still most of the time all that power doesn't ever get used. We have Magnpan speakers , Theil , Vanderstien which all require alittle more juice to make sound right. Some of the lower powered amps do struggle to bring out the best in them.

reeltrouble1

so its about current not watts....a novel idea, has that ever been presented here before.

RT1

tonyb

I'm with ya Ted, just seems as many times as it gets tossed around,few grasp the concept with any real understanding of it. We should have some sort of sticky on the subject.

TroyD

800wpc Class A? Nope, not even CLOSE.

While there is no substitute for radiating surface area and a man's amp.....as I've said, quality figures in there. All things being equal, yes....but, all things being equal is easier said then done.

BDT

FTGV

BlueFox wrote: »

I am more than happy with with my 800W (@ 4 ohm) per channel of Class A/B,Class A at low power levels then switching to class B watts at higher power levels. At low volume, the detail is impeccable. At 120db, it is still impeccable, but hard to talk on the phone.

I fixed it for him as I'm guessing that was his intent.

mhardy6647

TroyD wrote: »

800wpc Class A? Nope, not even CLOSE...

BDT

Indeed, can you imagine? A stereo amp at 800 wpc would be dissipating close to two kilowatts at idle.

I know that Mark Levinson (the real Mark Levinson) had Class A monoblock amps up to at least 330 watts (and they sound quite good actually - there's an occasional poster here who has a pair); I rather doubt anyone's marketed 800 watt Class A audio amps for domestic use.

Ricardo

FTGV

mhardy6647 wrote: »

I know that Mark Levinson (the real Mark Levinson) had Class A monoblock amps up to at least 330 watts (and they sound quite good actually -

Krell and Musical Fidelity also had some very big Class A units back in the late 80's .

I rather doubt anyone's marketed 800 watt Class A audio amps for domestic use.

Yikes.:eek:

heiney9

http://stereophile.com/solidpoweramps/699pass

Something like this would do the trick, not entirely class A, but 128wpc in A

The handsome X1000 monoblock under scrutiny here, the largest and most powerful amp in the Pass stable, makes 1000W into 8 ohms and a mighty 2000W into 4 ohms. The amplifier has no global negative feedback, and only two gain stages:

Each monoblock idles at about 600W, or 1200W for the pair—about the same as a pro-size hair dryer. The X1000 is biased for class-A operation up to 128W peak, beyond which it drops into class-AB. The amplifier typically draws about 5A (continuous RMS) from the wall during normal use, reflecting the idle current running through its output stage. If you're driving a low-impedance load hard it'll draw more, but both channels can be run on a single 20A, 120V AC line "without problems in most cases."

If you're truly power-mad, a number of X1000s can be arrayed to produce up to 2000W per chassis. Two of them can deliver 4000W into 8 or 2 ohms, four can deliver 8000W into 4 ohms, and 16 will do 32,000W into 1 ohm! The mind boggles. "As a practical matter, we would expect peak output levels on the order of 64,000W for such arrays." Yes, as a practical matter. Ahem. Your dealer or Pass can supply you with the interface adapter(s) needed to run the amps in series or parallel.

:eek::biggrin:

H9

heiney9

xcapri79 wrote: »

You don't need to have lots of things in this world, but having more than 200 watts in an amp is nice to have when you need it.

Simply not true and you can't generalize that statement. Watts is a very poor indicator of amp performance and shouldn't be the main factor.

H9

pearsall001

heiney9 wrote: »

http://stereophile.com/solidpoweramps/699pass

Something like this would do the trick, not entirely class A, but 128wpc in A

The handsome X1000 monoblock under scrutiny here, the largest and most powerful amp in the Pass stable, makes 1000W into 8 ohms and a mighty 2000W into 4 ohms. The amplifier has no global negative feedback, and only two gain stages:

Each monoblock idles at about 600W, or 1200W for the pair—about the same as a pro-size hair dryer. The X1000 is biased for class-A operation up to 128W peak, beyond which it drops into class-AB. The amplifier typically draws about 5A (continuous RMS) from the wall during normal use, reflecting the idle current running through its output stage. If you're driving a low-impedance load hard it'll draw more, but both channels can be run on a single 20A, 120V AC line "without problems in most cases."

If you're truly power-mad, a number of X1000s can be arrayed to produce up to 2000W per chassis. Two of them can deliver 4000W into 8 or 2 ohms, four can deliver 8000W into 4 ohms, and 16 will do 32,000W into 1 ohm! The mind boggles. "As a practical matter, we would expect peak output levels on the order of 64,000W for such arrays." Yes, as a practical matter. Ahem. Your dealer or Pass can supply you with the interface adapter(s) needed to run the amps in series or parallel.

:eek::biggrin:

H9

Now we're talking!!!! :biggrin: Five of those bad boys & I'd be in HT heaven...ah...two channel also! I probably couldn't afford the electric bill but who cares.

heiney9

pearsall001 wrote: »

Now we're talking!!!! :biggrin: Five of those bad boys & I'd be in HT heaven...ah...two channel also! I probably couldn't afford the electric bill but who cares.

Phil the current version (X1000.5) run about $34K/pr. So (5) of them would set you back over $75K..............I hope you invite me over once you get them dialed in!!!!:biggrin:

Of course used units go for less (if you can find any).............so maybe that's the avenue you could pursue

H9

cfrizz

heiney9 wrote: »

Simply not true and you can't generalize that statement. Watts is a very poor indicator of amp performance and shouldn't be the main factor.

H9

Right now his statement is as true as your generalization of not needing 200wpc. Until someone comes up with a better way of indicating what is needed to properly power speakers WPC is easy to understand verbiage for the most people to understand.

You want to get into all the nitpicking geekiness that goes into being an "audiophile" thats fine, but most aren't going to know what the hell you are talking about.

Again, this is about speaking plain english, and doing the best to ensure that people have gear that will allow their speakers to operate to their full potential no matter if they are play music or movies.

And we all know that for the most part receivers do not do this. And the gear that does do this that is less powerful is going to cost more money than the average person is going to be willing to pay.

All of this boils down to way too many variables that cannot be pidgeoned holed.

But I do agree that it is better to have it and not need it than to need it & not have it. No ones gear will be hurt with too much, but we damn well know that it will be hurt with too little.

FTGV

And for the budget conscience who can't afford the big Pass's.
Only $16k the pair.http://bryston.com/reviews/28bsst/ge_09.pdf

mhardy6647

The performance of a benign loudspeaker load (flat impedance as a function of frequency) would be quite deterministic and amplifier requirements 1) could be accounted for in terms of watts (i.e., according to Ohm's law P = I^2R = EI; 2.83 volts AC into 8 ohms = 1 watt) and 2) the simple rules relating electrical power, sensitivity, distance, and SPL I posted earlier would hold.

The problem is virtually all loudspeakers (especially today, with the exotic and poorly behaved drivers which are currently fashionable requiring complicated, sophisticated, and inefficient crossovers to compensate for their very poor out-of-band behavior) have complex (literally and figuratively) impedance plots; they are quite reactive loads. For just that reason, I would claim, power output specifications are poor predictors of amplifier performance in the real world - current capability is probably a better surrogate. Note that the power output of the Pass amp cited a couple of posts above doubles when load impedance is halved. That means it is capable of delivering the same voltage at twice the current into a load of half the impedance. In that case, watts will probably give you a reasonable metric for performance with a real-world load.

I have a feeling this is part of what H9 was getting at :-) I could be wrong about that, though.

The basic physics is actually pretty straightforward and deterministic. The Devil's in the details.

There are better-behaved loudspeakers (e.g., ribbon transducers which behave more or less as purely resistive loads) and worse-behaved loudspeakers (e.g., my beloved QUAD ESL-57s, which are essentially capacitors and can drive marginally stable amps into self-destructive oscillation - as could Polk's Cobra Cables).

cfrizz

mhardy6647 wrote: »

The performance of a benign loudspeaker load (flat impedance as a function of frequency) would be quite deterministic and amplifier requirements 1) could be accounted for in terms of watts (i.e., according to Ohm's law P = I^2R = EI; 2.83 volts AC into 8 ohms = 1 watt) and 2) the simple rules relating electrical power, sensitivity, distance, and SPL I posted earlier would hold.

The problem is virtually all loudspeakers (especially today, with the exotic and poorly behaved drivers which are currently fashionable requiring complicated, sophisticated, and inefficient crossovers to compensate for their very poor out-of-band behavior) have complex (literally and figuratively) impedance plots; they are quite reactive loads. For just that reason, I would claim, power output specifications are poor predictors of amplifier performance in the real world - current capability is probably a better surrogate. Note that the power output of the Pass amp cited a couple of posts above doubles when load impedance is halved. That means it is capable of delivering the same voltage at twice the current into a load of half the impedance. In that case, watts will probably give you a reasonable metric for performance with a real-world load.

I have a feeling this is part of what H9 was getting at :-) I could be wrong about that, though.

The basic physics is actually pretty straightforward and deterministic. The Devil's in the details.

There are better-behaved loudspeakers (e.g., ribbon transducers which behave more or less as purely resistive loads) and worse-behaved loudspeakers (e.g., my beloved QUAD ESL-57s, which are essentially capacitors and can drive marginally stable amps into self-destructive oscillation - as could Polk's Cobra Cables).

:eek::eek: Thank you for proving my point, that unless you took physics in school, I don't have the slightest clue WTH you just said!:eek:

I just want my speakers to operate to their full potential & discovered that it was accomplished when I got my 205wpc Parasound. End of story for me that is all that I care about.:biggrin:

cnh

I understand Cathy's position. There are two different things going on here. One is the original thread started by Brock which tries to stay on one topic concerning watts, current, design and sound, etc. The other often trails into HT and away from pure two channel sound but not 'entirely'. As in Phil's back and forth with Brock above.

To separate out the second thread. I think, most of us would agree that, for the person just getting involved in trying to power more difficult loads and supplement an AVR, etc. Power amps like Adcom, Rotel, B&K, Outlaw, Parasound, NAD and so on...rated from 100-200 watts/channel into 8ohms and more will certainly bring the average listener some benefits--especially since most all of these are HIGH CURRENT designs. At least more than his/her typical AVR.

If one wants to get into more subtlety and refinement and go beyond gross power levels in SS amps then, yes, the discussion above which was, after all, the OP purpose for posting to begin with, contains excellent information and debate!

cnh

FTGV

mhardy6647 wrote: »

The performance of a benign loudspeaker load (flat impedance as a function of frequency) would be quite deterministic and amplifier requirements 1) could be accounted for in terms of watts (i.e., according to Ohm's law P = I^2R = EI; 2.83 volts AC into 8 ohms = 1 watt) and 2) the simple rules relating electrical power, sensitivity, distance, and SPL I posted earlier would hold.

The problem is virtually all loudspeakers (especially today, with the exotic and poorly behaved drivers which are currently fashionable requiring complicated, sophisticated, and inefficient crossovers to compensate for their very poor out-of-band behavior) have complex (literally and figuratively) impedance plots; they are quite reactive loads. For just that reason, I would claim, power output specifications are poor predictors of amplifier performance in the real world - current capability is probably a better surrogate. Note that the power output of the Pass amp cited a couple of posts above doubles when load impedance is halved. That means it is capable of delivering the same voltage at twice the current into a load of half the impedance. In that case, watts will probably give you a reasonable metric for performance with a real-world load.

I have a feeling this is part of what H9 was getting at :-) I could be wrong about that, though.

The basic physics is actually pretty straightforward and deterministic. The Devil's in the details.

There are better-behaved loudspeakers (e.g., ribbon transducers which behave more or less as purely resistive loads) and worse-behaved loudspeakers (e.g., my beloved QUAD ESL-57s, which are essentially capacitors and can drive marginally stable amps into self-destructive oscillation - as could Polk's Cobra Cables).

Best post in the thread.I enjoy reading your accurate informative responses.

TroyD

I understand Cathy's point....but, the reality is that truth be told, unless you have, oh, some Carver Amazings (the Originals) or Apogee Scintillas, 200 wpc meaningless.

Lets put it this way. The difference between 100wpc and 200? 3 db. That's it.

I'm willing to bet that most of you never use 10 wpc. In fact, I can drive you out of my house with a 15wpc Marantz receiver.

I get it. 200 wpc makes you feel good. You like your amp. I have zero issues with that. The fact is, save for a few of you, the reality of your actual power consumption is a VERY different story.

BDT

cnh

A friend of mine has a Ph.D. in Solid State Physics, I may have to ask him to post for me a few times?

Just kidding, I actually enjoy trying to piece out the tech-speak. Just be grateful I don't hit you all with the writing that I have to plow through in my field because nobody would have any idea about what 'we' are talking about. But that's true in any field of specialization.

Good Discussion....keep it coming!

cnh

pearsall001

heiney9 wrote: »

Phil the current version (X1000.5) run about $34K/pr. So (5) of them would set you back over $75K..............I hope you invite me over once you get them dialed in!!!!:biggrin:

Of course used units go for less (if you can find any).............so maybe that's the avenue you could pursue

H9

Brock, most likely not in this lifetime! But then again one never knows what tomorrow might bring. Maybe the lottery gods will feel sorry for me & send one my way!!! That reminds me maybe I should pick up a couple of tickets just to be on the safe side. :biggrin:

BlueFox

TroyD wrote: »

800wpc Class A? Nope, not even CLOSE.

Sorry, for not being engineering precise. :rolleyes:

In bridged mono mode they are rated at 800W/ch into 4 ohms. Class A for some initial number of watts, and then switching to class B. I have not been able to find any spec, or review, where they say at what point it switches between class A to class B. However, since I mostly listen to classical in the 60-70db range I suspect most of the time it is operating in class A mode. It sure generates the heat for that. I love it in the winter, but in the summer it can get unbearable. I need to get the AC fixed.

Last night I did an experiment after I posted. I just threw out the 120db number. Its purpose was not be an exact figure, but just to indicate that when it is loud it still is clear and precise, but you cannot talk to the person next to you. I put Lady Gaga on and cranked it up to 105db. That happened at -35db on the dial. Anyway, at 105db she was just loafing and more than happy to go higher, but I chickened out since I did not want my neighbors calling the police.

megasat16

BlueFox wrote: »

Sorry, for not being engineering precise. :rolleyes:

In bridged mono mode they are rated at 800W/ch into 4 ohms. Class A for some initial number of watts, and then switching to class B. I have not been able to find any spec, or review, where they say at what point it switches between class A to class B. However, since I mostly listen to classical in the 60-70db range I suspect most of the time it is operating in class A mode. It sure generates the heat for that. I love it in the winter, but in the summer it can get unbearable. I need to get the AC fixed.

Last night I did an experiment after I posted. I just threw out the 120db number. Its purpose was not be an exact figure, but just to indicate that when it is loud it still is clear and precise, but you cannot talk to the person next to you. I put Lady Gaga on and cranked it up to 105db. That happened at -35db on the dial. Anyway, at 105db she was just loafing and more than happy to go higher, but I chickened out since I did not want my neighbors calling the police.

Even though your amp may not make 800WPC @ 4 R Class A, you are not entirely wrong.

There are amps that makes 800WPC@4R Class A.

Certainly, the ML # 33 that Mark (mhardy) pointed out is very close to making 800WPC@4R while being in Pure Class A.

And there are some old Krell Pure Class A amps that comes close to that number.

And there are other Class A amps even though they use different Class A biasing scheme and (purists insists they are not Pure Class A) that reaches out 800WPC@4R number easily.

But biasing an amp in Pure Class A form is so damaging to the amp itself for the ML#33 and some Krell amps. The anodized coatings on the heatsink will change color with time due to the extreme heat they are dissipation while just sitting idle.

Nonetheless, I love Pure Class A amps and my 60WPC pure Class A (not Pass Amps by the way :biggrin:) amp is driving my Amazing Platinums now. There is enough power (current) capability to drive amazing to very loud levels.

shack

TroyD wrote:

I understand Cathy's point....but, the reality is that truth be told, unless you have, oh, some Carver Amazings (the Originals) or Apogee Scintillas, 200 wpc meaningless.

Lets put it this way. The difference between 100wpc and 200? 3 db. That's it.

I'm willing to bet that most of you never use 10 wpc. In fact, I can drive you out of my house with a 15wpc Marantz receiver.

I get it. 200 wpc makes you feel good. You like your amp. I have zero issues with that. The fact is, save for a few of you, the reality of your actual power consumption is a VERY different story.

BDT

BINGO!

And that my friends...doesn't take a physics degree to understand!

newrival

cfrizz wrote: »

:eek::eek: Thank you for proving my point, that unless you took physics in school, I don't have the slightest clue WTH you just said!:eek:

I just want my speakers to operate to their full potential & discovered that it was accomplished when I got my 205wpc Parasound. End of story for me that is all that I care about.:biggrin:

If you stopped experimenting after your 205W parasound, how do you know they're opperating at "their full potential." Them sounding better than they ever had before is not synonymous for their full potential. you boiling down your situation to an issue of wattage is a highly undeveloped conclusion at best. I believe for many (and likely, yourself as well) it is an issue of proving your own foregone conclusion. Likely what happened in your situation was that the lower power amps were lower quality in general, and regardless of wattage, were never going to deliver quality sound anyhow, i.e. had less current, had heat issues at low impedence, etc. In all probability, saying "get an amp with a minimum of 200W" to an iquiring newcomer to audio will get them an ok amp. However it is more due to the fact that the amp will have better components and specs more conducive to good audio reproduction (in low priced/used amps) and NOT because of the wattage. Your advice to do so, while accidentally helpful, is very misleading, and I think there are dozens of posts here explaining why. If you're happy with sticking your head in the sand and believing it wattage, fine. But just because you want things to be overly simplified, doesn't mean others do.

cfrizz

cnh wrote: »

I understand Cathy's position. There are two different things going on here. One is the original thread started by Brock which tries to stay on one topic concerning watts, current, design and sound, etc. The other often trails into HT and away from pure two channel sound but not 'entirely'. As in Phil's back and forth with Brock above.

To separate out the second thread. I think, most of us would agree that, for the person just getting involved in trying to power more difficult loads and supplement an AVR, etc. Power amps like Adcom, Rotel, B&K, Outlaw, Parasound, NAD and so on...rated from 100-200 watts/channel into 8ohms and more will certainly bring the average listener some benefits--especially since most all of these are HIGH CURRENT designs. At least more than his/her typical AVR.

If one wants to get into more subtlety and refinement and go beyond gross power levels in SS amps then, yes, the discussion above which was, after all, the OP purpose for posting to begin with, contains excellent information and debate!

cnh

Thank you, you get what I'm trying to say. I keep it simple for those who want simple answers that will give them positive results, for those who want to experiment with the more complex issues of this hobby, they are welcome to plumb the depths of knowledge here as well.

newrival

oh by the way, h9

i love the thread. it has to be one of my favorite topics in audio. By the way, I'm now driving my SRS's with a 70wpc Classe amp because of some of your and DK's links and endlessly useful comments and have never heard them sound better. Although I have a Forte amp that I've been listening to that is right there with it.

Hoping to try a J-FET sometime in the future.

mhardy6647

I am not the least bit interested in this topic ;-)

Might I just mention that there is only one Class A: it means output devices biased "on" 100% of the time. No ifs, ands, or buts. It is extremely inefficient; an amplifier operating in Class A dissipates maximal power at idle. It actually runs a trifle cooler when amplifying signal! But a Class A amplifier will not have (can not have) any waveform crossover or "notch" distortion.

megasat16

Hehe...Mark, you just reminded me to go and listen to my amp. I let it sit idle since a couple of hour ago.

This Class A amp grows likes Gold in the Sun. No stinking Tube needed.

Pure Class A doubles down all the way to 2 ohms load. The whole chassis is essentially the heatsink to dissipate heat. Sweet and Pure as snow (not you Snow :biggrin:) but feeling guilty as hell just leaving it on.