SS amps. Why so much power?

I though that there was so much tube amp talk on this page lately, I'd put up a SS thread. Why do so many people buy the big SS amps that have 200,300,500 watts of power? Is it because the speaker you want is inefficient and you need lots of power, or do you need to play real loud? Or is it a status thing, like my amp's bigger than your amp, or what? Do you buy a big amp first, and then look for a speaker with high power handling? Or do you pick a low efficiency speaker you like and then look for a big amp to drive it? Do you subscribe to the idea that if you have alot of watts, the amp will sound better at lower volumes? I've noticed that the majority of AudiogoNers go with high power SS amps and low efficiency speakers. What gives?
Twl, my speakers are quite inefficient and the more the power the better they sing. My amp is rated at 600 wpc into 4 ohm loads. Not the most powerful, but certainly not the weakest. I purchased the speakers before the amp.

My previous amp was a nice amp in so many ways and rated at 195 wpc into 8 ohms. But I could tell that the lower regions seemed to be compressing a little at about 1/3rd full volume.

I believe the system will sound better at low volumes if the amp is designed well, has the power reserves, and if the AC electrical has been configured so as not to choke the AC power needed for the amp during dynamic swings i.e. a dedicated circuit/line.

I rarely play my system loud. But its nice to listen knowing that the system has the necessary elements to play at any volume without fear of strain, congestion, compression, etc..
Kind of like having a Corvette,it's nice to know you can do 165 if you need to?
Better to have it and not need it, than need it and not have it. It probably depends how low of frequency your speakers are capable of too. As lower notes require substantially more power. Remember, more speaker drivers bite the dust from low powered amps than high powered amps.
I want an amp that can drive any speaker made.
"Confusion"...... are what the so-called mainstream hi-end is all about........ Very, very sad........... The major cause of this is inefficient speakers............
What else can they gonna talk about? I'm not enough of a regular to comment on the makeup of AGoners, so I'll just speak of myself. I've been involved in audio for 26 years, though only aggressively in the last 6 years. After listening to my first tube amp (Dynaco st70) IMS I knew what kind of sound I was after. Ever since I've defied convention and built my system(s) around tube amplifiaction. I'm now on my third tube amp and feel confident I'll hold on to this one for awhile. In fact, I loved my last amp. I only sold it to fund my first SET amp.

The Moth s45. A custom amp with upgraded parts, is switchable between 2a3 (5wpc) or 45 (2wpc) output tubes. The coupling speaker? Silverline Sonatina - 93db. Suprisingly this unlikely pairing has worked out better than I expected. I'm still looking into horn-loaded or single-driver speakers but in the interim I'm enjoying the highest level of replay I have witnessed IMS. Not everyone is power hungry.
I think the reason some use a high wpc amp is ego.
My d*&%k is bigger than yours type mentality.
I have a friend who has a 240wpc amp with 88dB speakers.
Mine is 30wpc with 92dB speakers.
His plays loud.Mine plays loud.Is his louder?? maybe a bit but who's going to listen that loud? Im a head banger.I get more than enough volume with my set up.
My amp sounds great at low volume or high.
It makes no sense to pay for watts you wont use.
Wanna go deaf? get a high wpc amp and blast it! Want music? get a low watt single ended amp and blast it or just enjoy it at a safe level.
For me, it's a matter of bass control and slam. My speakers are 91dB efficient, but have 15" bass drivers. Lower powered amps just don't control the woofer as well, at any volume. Very noticeable in the low bass region (below 30 Hz). My $0.02
I guess it depends on the person. For me, I had 87db speakers with an SS amp that was around 35wpc. It just didn't sound good to me. Even at 1/3 or less of full volume, the speakers sounded thin and lifeless. Then I got an amp that had 175wpc into 8 ohms and 250 into 4. It really made a difference for me. Everything sounded fuller and less strained. Perhaps if I went for a 300-400 wpc amp it would make more difference yet? I don't know. But I'm glad I upgraded in power.
Most solid state amplifiers prefer low impedance speakers. Most tube amplifiers prefer higher impedance speakers. On a reasonably high impedance speaker, a much lower powered tube amplifier should be able to drive the speaker better than a high powered solid state amplifier.

A good example is the SoundLab speakers. They have a reasonbly high impedance through much of their curve and will generally laugh at higher powered solid state amps, while a 220 watt tube amplifier, like the Wolcott (Hi Albert & Duke), has no trouble with them whatsoever. Even much lower powered tube amplifiers do a very nice job on them.
Greater control of the speaker plus I play my music loud occasionally and having more power than I need means that I will not clip the amp which is the best way to blow up a pair of speakers.
Edle, Based on that statement one could easily get the impression that you think the only thing all amplifiers do is amplify.

That is exactly what an amp is suppose to do, but very few actually do just that.
1)A true audiophile, i think, buys the amp that will allow their speaker to best do what it does, including decent SPLs. My speakers as well as others' just require high power to really do anything at all.

2)The mid-phile will buy the most powerfull because they believe to be the most important of the few dimensions they consider. They are stuck in the land of nominal, printed ratings.

3)The nonaudiophile will buy the biggest penis extension they can afford.

Varying combinations of 1, 2, and 3 for each person at a given time drives amp selection.
David, no "headbanger" would ever be satisfied with a 30 wpc amp ( regardless of make, model or designer ) and 92 dB speakers. Either the amp would be smoked from overdrive or the tweeters and mids would be cooked from clipping. As to "who's gonna listen to it that loud", you might be surprised. I have locals that light power transformers on fire, blow the piss out of speakers on a regular basis, etc... Obviously, some people DO listen to music "LOUD" and i don't mean "Audiogon loud". I'm talking POUNDINGLY loud and they still want it crystal clear.

If it all boiled down to "bragging rights", you would need someone that knew what you were talking about to brag to. Since the general population all think that Bose is good and flea market car stereos have a "real" multiple thousand watt capacity, we'd be wasting our time and money.

Like anything else, people invest their time and money seeking the results that will make them happy. Since playing at high volume with good clarity and control typically takes a lot of driver surface area and power, that is what they spend their money on. I know what i want and am willing to pay for it. I'm sure that others with complex systems with high wpc ratings feel the same way.

As to why i have a lot of power, most of the speakers that i prefer to listen to are a combination of low impedances, low sensitivity and have a lot of driver surface area. In this respect, Edle is right. It does make for a tough climb up-hill but those are MY preferences and i have to deal with them. This takes a LOT of muscle to keep things under control and still not sound like something is running on the ragged edge. I also prefer to let amps coast as they typically sound less congested and more refined that way. Headroom in a system means not only the ability to easily reproduce peaks and maintain dynamic range, it means "lack of strain". This way, you can achieve "cranking" volume levels without really "cranking" the amp hard. Even if you are drawing 300 - 800 watts on long duration peaks, having 1000+ wpc on hand simply means that you're still coasting.

While this may not be nearly as critical on classical, jazz, blues, etc... due to the very high peak to average ratio, rock and metal require much higher levels of average power to sustain "concert levels" and keep it clean.

While this is not meant towards anyone in specific, until you've heard and experienced ( and especially assembled ) a system that can literally raise the roof, do it with the utmost in clarity and control and do it on a continual basis reliably, you have NO idea what you're missing or what it takes. This can't be done with a couple hundred watts per channel and average efficiency speakers. It takes MEGA watts and a lot of surface area ( drivers ) which results in low impedances which means you have to have even more power capacity. Achieving the "ultimate" becomes a vicious circle rather quickly.

That is, unless you're using very high efficiency horns and that sound suits your tastes. Even with 104 db horns, i have driven 300+ wpc amps into clipping. Impressive to anyone ? No. Trying to achieve what i personally want out of a system ? Yes. Offensive to some ? Possibly ( neighbors especially ). Not quite as offensive as talking about comparing the size of ones' "johnson" though.

All i can say is that some of you need to wake up and smell the coffee. Once you do that, you'll realize that there are different brands, types and preferences for "coffee". Even with all of the different variables involved in just that, some people like to "flavour" theirs even beyond having a custom blend. Audio is no different and there is no "right" or "wrong". Just what makes YOU happy as an individual. Sean

Jtinn, NO amps really "like" low impedance loads. While it is true that SS amps typically deal with low impedances in a more linear fashion than tube amps do ( and high impedances vice-versa ), they ALL suffer from reduced damping factor, increased heat and thermal losses, increased distortion by-products, etc... This typically results in poorer sound quality overall. I'm sure that there are exceptions to this "rule", but they would be far and few between. Sean
Sean Nice post and very polite.
I will make a useful analogy.
If I am in shape and I bicycle 50 miles on a sunday it is an enjoyable exercise.....I sweat but I am in my groove and moving well. When I am not in such good shape that sam trip is not enjoyable at all. I might even wobble on the road as I huff and puff up hill and then are forced to coast downhill. (I live in san diego and I do alot of cycling.)Power amplifiers are very similar. To be able to appropriately recreate a human singing voice belting out an aria from traviata or tracy chapman it takes alot of power, alot of reserve and alot of headroom. The less powerful amp will do it but less beautifully.
Good God, Sean, what must your hearing loss be like these days?
Sean: So are you saying that a fairly average 100 watt solid state amplifier would prefer to drive an 8 ohm load to that of a 2 ohm load?
Well, i know that i can still very easily hear 15 KHz at about the same amplitude that i can hear 1 KHz ( give or take ). 17 KHz is there, but not as strong. I should probably go in for a hearing test sometime soon. I know that i had some slight irregularities in the upper mids / lower treble from ear to ear.

Other than that, i can pretty easily detect amplitude changes well under .5 dB at 1KHz, as i have to do so on a daily basis at work. I typically tune communications receivers by ear but have a Sinad meter ( signal to noise ratio ) there to confirm what my ears tell me.

In terms of hearing acuity and localization, a salesmen told me that i was the only one out of hundreds that was able to point out where a subwoofer was hidden during a Stereophile show. My brother, who is 12 years younger and standing right beside me, did not know where it was coming from and picked another section of the room. Obviously, i'm not anywhere near being deaf. Sean

PS... I apologize for the small explosion above. It just pisses me off when "open minded" people can't see other people's point of view. Especially when it comes to something that is so obviously subjective and personal as musical preferences and system selection.
Jtinn, how do you measure "preferences" of electronic devices ? What are you basing your criteria on to say what it likes best ?

If it is simply measurable power output, you will find an impedance where an amp will peak at and then fall off both below and above that. As mentioned above though, distortion and heat dissipation ( loss of efficiency ) will climb as impedance is lowered. Obviously, most any device will have a "sweet spot" where it will perform best i.e. reasonable distortion and heat generation with good power ouput. All things being equal, a SS amp will "prefer" or work optimally into a lower impedance than a tube amp would.

This is not to say that all SS amps work optimally at low impedances though. This is evidenced by their lack of ability to "double down" as impedance is halved. While a true "voltage source" would do this, there are very few amps built anywhere close to that. Some obviously do better than others in this respect.

If an amp was a true voltage source though, it would not matter what impedance was presented to it. The power output would increase or decrease at a linear rate as impedance was halved or doubled. As such, the amp might do more power at lower impedances, but that doesn't mean that it was running optimally there. The point of optimal operation ( or what it "liked best" ) would be that of highest efficiency with the lowest distortion. Depending on the design, that could be at any specific impedance, not necessarily the lowest possible.

Besides all of the above, damping factor is lowered as the speaker impedance is dropped. This results in less control over the drivers with greater susceptability for the reflected EMF to "modulate" the power supply of the amp. This is the reason why some amps sound good at low impedances and others don't. Their "linearity" goes out the window even though power output might increase. Sean
For me personally, I found a set of speakers that I really loved and have found over the course of a couple of amp upgrades that they sound markedly better with beefier amplification. I didn't set out to own a big amp, but the sound I liked led me there. I've got nobody to show it off to, and if I did show it off to most people I know, I'd be labelled crazy rather than cool, so I don't think it had anything to do with status.

And while I agree with Sean that high-end audio isn't bragging material to a general population that believes Bose is the ultimate, the one thing that WOULD generally be understood as "awesome" by that same general population would be telling them that "my amp has 1000 watts per channel" (mine doesn't, BTW). Since those same people have learned that more watts == better amp, that's impressive. -Kirk

Well, my hearing isn't as good as Sean's anymore but it won't stop me from putting 2cents worth in. Designing speakers is a trade off, no? You cannot have 1) a small speaker, 2)an effecient speaker and 3) bass. (see Lots of people like fairly small speakers (spouse appeal, size of listening room ect)and therefore effeciency is often given up. This requires more power and its lots of power. If you listen at 5 watts nominal, because you have an ineffecient speaker, and want to handle a 20db peak you need about 640 watts of power right? Otherwise you clip.
Maybe I'm way off base here, but isn't part of this the way that amps clip? I always thought SS amps clipped in a manner that sounded "bad" and therefore having lots of headroom to deal with transients is "good".
I'll admit that the following is a gross exageration but (here it goes, I know I'll be eaten alive by some of you) I find most speakers with decent bass present a low numerical impedance load. Have mercy!
Nearly all the speakers manufacturers put cheap drivers with ceramic magnets into all their hi to low end speakers. Also the sealed box speaker design also a major contributing factor in lowering the over-all efficiency of the speakers. As audiophiles, the "only weapon" to
"compensate" are to use powerful amps(SS or tube). Bigger is better! That's why nearly everybody have big powerful amps and hope that the speakers will become less stain, congest, compress or less distort...........
In the SS case it's imperative to keep away from clipping as far as possible. That's the way the transistor will operate linearly. Getting even close to clipping will result a large scale of distortions. Clipping can result the driver damage and blown transistor(s). Tubes clip less dangerous to itself and speakers as well.
Re: volume, I once had a musician friend( trombonist) visit me, who upon walking in my door exclaimed "isn't your stereo kinda loud?" I replied that I was trying to replicate the the sound of the original performance ( a small jazz combo playing a mellow bluesy piece) to the scale of the room and distance from the sound source. He just happened to have his horn with him, so I invited him to play along with the recorded music. He was astonished to find that he couldn't play softly enough to properly accompany the music. Now, I believe two things were going on here. One, that a trombone wasn't designed to play in an average living room, but in a larger concert hall. Two, most people (not you dear readers)are accustomed to low quality "Hi Fi" systems that distort terribly at anything above low volumes (Especially those who mostly listen to TV (not serious home theatre)). In anticipation of horrid above low volume sound in a typical home environment thier defences arise before relaxing and allowing themselves to enjoy the moment.
sean-get yourself a high current ~30 wpc amp.match with 92dB some clean recordings in a 15x20x7 foot room THEN say "no headbanger would ever be satisfied with a 30wpc amp"
I listen at loud levels with room to spare.
I have excellent bass slam but with the midrange purity only a single ended amp can offer.
sorry if my remarks offend you.Its only a hobby ya know.
over and out....
P.S. this same musician friend had pretty good ears. After settling down and listening he shortly there after went out and replaced his Sansui and Proton equipment with Rotel, Creek and Linn. To be fair the previous equipment he had was probably the best that was available to him at the local appliance store. He had no previous knowledge of High End stores.The last time I visited him he was playing his music at a much greater volume than I usually do!
David, i've used two different SS amplifiers that were biased Class A, were rated for 40 wpc and 50 wpc, doubled down at 4 ohms and were from the same manufacturer that you're currently using. These powered a set of 96 db speakers in a room appr the same size ( probably slightly smaller ) as to what you mention. It was never loud enough while retaining the clarity that i was looking for when trying to throttle the system. Hence, i upgraded to a far more powerful amp from the same manufacturer and things improved quite measurably.

Having "been there, done that" many times over, i have to laugh at thinking that one could achieve "headbanging levels" with the amount of power and efficiency of speakers that you mentioned in a room of that size. That might be an excellent system for doing chamber music but it is surely NOT suited for trying to reproduce "metal" at "headbanging levels".

As to offending me, i think that your comments were offensive to everyone that currently owns, has owned or may be thinking about purchasing a high powered amplifier. Not only did you pidgeon hole all of these people from various walks of life with different philosophies into one category, you also insulted them by commenting on their "johnson-sized" mentality.

It might only be a "hobby" to you, but it is one of the passions of life to others. Either way, one should think before speaking or posting. Sean

If you want to controll the bass and move some air, and have the speakers to justify it, you need the power, tube or SS. Bass peaks suck power no question. The more inefficient the speakers the more power you will need if you are chasing bass. You can even hear large club systems run out of gas when underpowered and then the bass gets sloppy and the dynamics go away. I use about 230 wts (tube)a side at home with one 10 inch bass driver per side. in the clubs i use a 45 wt tube amp for guitar that never gets above 3 because it will overplay the PA, And to drive 2x18 per side we use about 1600w just for the bottom, Good bass+ lots of juice.
Lets see if AudiogoN will let this one in.
sean-enjoy your mega watt headbanging amp and I'll enjoy my low watt headbanging amp.
There,that should pass the moderators.
As some of you might have guessed, David and i have been going "round and round" via email. Since much of our conversation pertains to information that might clarify either or both of our positions, i am responding to one of his emails publicly. This will give some of you a better idea of where i'm coming from. This may help to clarify the situation and ease some tension.

David stated that his system ( 30 wpc Class A driving 92 dB speakers ) plays almost as loud as a 250 wpc Krell driving 88 dB speakers. I believe that 100% and would never argue that point. It takes a LOT of power to overcome measurably higher speaker efficiency. I just don't think that either set-up is "loud" nor would it be "clear" due to amplifier strain when cranked up. With that in mind, David and i might not have been as far apart in perspective as it seems.

As such, I think that there have been some large misconceptions as to where i'm coming from. Most people think of a 250 wpc amp as being "BIG". It's really not when you get down to it ( unless you have HIGH efficiency speakers ). In order to achieve the levels of volume with the clarity that i speak of, David thought that i would need something along the lines of a Krell 600 to do the job. I agree that this would be a good starting point. I still don't think that it would get you there due to power losses and distortion in the passive crossover network and out of band power being fed to the drivers. The beauty of active multi-amping is that it bypasses all of that AND increases amplifier efficiency and headroom at the same time.

This information is presented here STRICTLY as a point of reference to why i have said the things that i have about volume levels and clarity. You'll also understand why i said that 250 wpc is not a lot of power.

My main 2 channel system consists of six stereo amplifiers that are actively tri-amped and total 4800 watts of rms power. It consists of amplifiers built and designed by Threshold and Perreaux. Speakers consist of three different sections per side. There is a line array of e-stat tweeter panels, a set of "double stacked" e-stat panels for mids and multiple woofers for each side.

My HT system is rated at 6400 watts rms at the rated speaker impedance, all channels driven. Amplifiers are a Sunfire Signature driving the mains and a Sunfire Cinema Grand Signature driving the center, surrounds and subs. I have six 12's, four 10's and six 8's in this system, so power handling, max spl and low frequency response is not a problem.

My bedroom system is currently bi-amped and may be going to tri-amplification sometime soon. It currently consists of two identical amps ( Quad's ) rated for 100 wpc. Speakers are stand mounted two way monitors and a pair of downloaded subs.

My computer room system uses two Kinergetic Class A mono-blocks into low impedance omnidirectional speakers. Each amp is rated at 800 watts rms into those speakers. While these speakers won't "crank", they do require at least 350+ wpc to let them do what they are capable of doing.

For the record, i do have a "low powered" system. It consists of a vintage Marantz tube amp driving 104 db horns. Some of you may have seen me recently posting a question about this in the Vintage Asylum.

Unless you've ever heard a system that has nearly endless reserves of power and you can move a LOT of air rather effortlessly, you've never heard "loud and clear" before. As i've mentioned before, most of what people think of as being "loud" is actually "distortion byproducts" hurting their ears. I'll leave it at that and hope that some of you can more clearly understand my point of view. Sean
Hey Sean, I have never doubted the truth of the position you are laying out here - for your stated purposes only. And I'm glad your hearing is still intact (though I didn't quite need the full auditory report - I was making a j-o-k-e). Now the only thing I am wondering about is why anyone would want to listen to "metal" in this fashion! (Peace - that was another one.)
Sean-Nice post.To clarify a bit more.I mentioned 2 Krell 600's and a pair of Grand Utopia's 93db?? This was in response to Sean e-mailing me stating I had given him the impression I was claiming to get "bone crushing,concert level" volume from my set up.
I 'shot back' it would take the Krell and Grand Utopia set up to achieve that(maybe)
I never claimed anything close to that kind of volume only that I get sufficient volume with head room for metal music.
Maybe what it comes down to is:
1) "loud" is in the ears of the beholder
2) Im a headbanger imposter
3) it does take 8000wpc to be a true headbanger
4) this is ridiculous
If I offended anyone wih my big D&%#K remark Im sorry.I can be crude at times.I know Sean was a little offended and I am sorry for that.
Sean- this is our first exchange here on the 'gon.