Amplifiers weight

What does amplifiers weight has to do with performance?
im trying to decide between this 3 amps
parasound JC5 73 pounds, Anthem STR 60 pounds Michi S5 by Rotel 132 pounds 
I can get them around the same price 
my speakers is modified klipsch KLF 30
preamp is Michi P5 and a pair of SVS SB16 ultra Sony Hap Z1 and Cambridge Azur 851N
i really like the looks of STR amp 
Will you be paying by credit card, cash, or check? After carefully weighing all the options, pay with the one that weighs the least. That will get you the absolute most, pound for pound, of anything.
What does amplifiers weight has to do with performance?
  • Larger transformers weigh more
  • Larger capacitors (and/or more of them) weigh more
  • Thicker chassis material weighs more
Otherwise, not too much.  A thick face plate and heavy footers weigh more but those may or may not have an effect on performance.  However, there are many other factors that may affect performance but not weight, including the circuit design.
This just in! Exciting news! Amplifier science (like climate science only credible) proves amplifiers fall at the same rate regardless of weight! But- and here's the catch!- only in a vacuum! Which raises the question, how likely are you to be dropping your amplifier in a vacuum? Not bloody likely! Therefore, logically, buy the lightest amplifier you can find. It will be more likely to work when you drop it.
Very little.

I have 5 lb. Class D amps that sound a lot better to me than many 60 lb plus amps.  I did end up with a heavy integrated, but this goes to show you that weight alone is not the issue.

Unfortunately, weight and physical size are equated with value, so of course, mega amp makers add as much heavy metal as they can.

In a linear amp, you DO want the beefiest transformer you can get, but you can’t really separate that from the weight of the chassis, nor can you evaluate that in light of the rest of the circuitry.

Get the cheapest lightest amp you like the sound of. :)
Get the cheapest lightest amp you like the sound of. :)

You mean the sound it makes when it hits the ground?

While your question was poked fun at by some, this exact question came up for a friend and I yesterday. Why? Because weight is touted as a "pro" for some amps and we didn't know why. Your question elicited some good reasons.
I reckon you guys ain’t heard of the ultra-low mass amp craze that’s sweeping the nation. I use an ultra-low mass portable CD player with headphones. Total mass less than two pounds. No big honking transformer, or big honking capacitors, monster power supply, no big old power cord, no fuses, no interconnects or big honking speaker cables. Or their attendant noise and distortion. No more pencils, no more books, no more teacher’s dirty looks. 🤨
While your question was poked fun at by some, this exact question came up for a friend and I yesterday. Why? Because weight is touted as a "pro" for some amps and we didn’t know why.

Its called: marketing. 
See: Mark Levinson.
Let me see.... two plus... carry the one... Holy crap! $2278/lb! I knew the iPhone was overpriced but this is crazy!
Power Supplies: Commentary for Consumers. by Nelson Pass

Power transformers

The best power transformers are toroids, with donut shaped magnetic cores. They pack the most power for weight and size, and they make less noise. Toroidal transformers have to be rated at a minimum of several times the intended wattage because the power is delivered in short pulses to the capacitors.

Typically, a Class AB stereo amplifier rated at 200 watts per channel continuously should be capable of delivering 700 watts or so, and this means a transformer rating of about 2000 watts. Anything less means non-continuous operation. This might be alright for a class AB amplifier where maximum continuous operation is not required.

If the stereo amplifier is rated 200 watts per channel pure Class A, it will draw about 1000 watts all the time, meaning that about 3000 watts of power transformer is called for, no less.

Now a toroidal transformer delivers about 30 watts per pound, so a 3000 watt toroid will weight about 100 lbs, maybe more. The rest of such an amplifier will probably weigh about as much, so if you are looking at a 200 watt per channel stereo Class A amplifier, you will want to see if it weighs at least 200 lbs.

One pound of weight for every 2 watts is a good litmus test for evaluating Class A amplifiers. An amplifier weighing less might not be pure Class A. It might be almost Class A, or it might be one of the many products which achieve a Class A designation through trick circuitry.

To lower noise still further, toroids are sometimes encapsulated in metal cans. To reduce magnetic radiation, these cans are usually, but not always, made of steel. This is good, but be aware that in the past, at least one company has used a small transformer in a big can, and made up the difference with sand.

The answer is, in other musings from Nelson, is that a 200watt class a/b power amplifier, should weigh at least 50lbs. The larger part of that mass being the transformer. As in a good 25lbs.

Heat sinks, about 7-8 lbs per channel. maybe 10lbs per channel. then the chassis, about 10-15 more lbs.

Faceplates of solid aluminum cost a lot to make,and weigh a lot... so don’t waste your bucks on them and don’t make the manufacturer do it, just because it looks cool and makes you rub your nipples in excitement. circuit bards weigh the least, a few pounds. Capacitors in the power supply another 7-8-10lbs. so we end up near or at +60lbs for a proper 200 watt per channel class a/b power amplifier. Which is why, if one minimizes but tries to meet the proper spec, we end up at Nelson’s stated low end of ’at least 50 lbs’.

Here we see a 1500va transformer, coming in at 30lbs shipping weight, most of that being the transformer itself.

When we look inside a classic Adcom GFA-555 power amp, we see a 600va rated power transformer, which is actually quite pitiful, with regard to current delivery. No balls at 4 ohms. We could drop the afore shown 1500va transformer in there, and then do some mods to the amp, so it can belt out full proper power at 4 ohms. the work would be extensive and flakey, ie subject to failure as the thing is not really built for it.

Just buy a ballsier amp with a proper power supply, if we feel we need the extra but proper power at 4 ohms...

to be blunt, the vast number of 200 watt per channel power amplifiers will NOT have that 1500VA rate transformer in it, they will poses something much lighter and wimpier. the only middling one that actually delivers that, that I know if, is the belles 450, where David Belles, added in a 1500va transformer. It looks like a undersized curling stone. I'm sure there are many more amps like that, this is just one I remembered at the moment and have owned 4 of over various times. Belles 450, no wasted mass, and half of the 57lbs, is the transformer. As it should be.

To go to the right area, where it is all ’done right’, we have to move up to the big boys and their extreme power supplies, all done for mucho cash outlay.
Just buy the one that is the nicest looking to you.  After all, that is all that really matters.  They all sound the same anyway!

Happy Listening.
Thanks everyone for inputs
I learn a lot 
so is not always about the weight 
some of emotiva and outlaw stereo amps weigh a lot my current amp A21+ weighs 72 pounds sounds amazing but anthem STR amp is too gorgeous  can’t stop looking at them
I don’t really need more power than A21+ for my current set up just to cover future upgrade
The Michi S5 looks great but 130 pounds no then I need to change my rack and I’m not ready for that  
The preamp looks amazing though for 4K
As noted, the size of the transformer is important. Inductors too, and heat sinks are heavy. The bigger the heat sink, the lower the operating temperature, for given heat dissipation.

The amount of real estate inside the enclosure is also important. If the big electrolytic caps are close to either the output transistors or the rectifier, or their heat sinks, they age prematurely. Obviously big enclosures weigh more.

If you live in a rich radio environment, thick metal is a good shield for your delicate electronics, although good layout can substitute. So again, all things being equal, heavier is better - the only problem is that all things aren’t often equal.

Finally, if a guest stubs his toe on 100Kg slabs of aluminum, that toe stays stubbed. Better that than the amp.
Weight has nothing to do with anything unless you are carrying it up 3-4 flights of stairs. So either buy a lighter amp or work out more. 
I have never heard a class d amp, or for that matter, a Rotel, sound musically engaging. Get the Anthem or Parasound. I love my 65 lb Luxman class A!
Regarding the Michi:

Honestly, I would never buy any solid state amp that needs 2 fans to keep it cool.
Thanks @cakyol , that was an interesting read.
Pass’ thoughts on weight vs. power and amplifier class, and the benefits of a suitably large power supply, seem logical but from the standpoint of sound quality there must be more to it since he continues to design new amplifier lines that apparently sound different/better than his previous amplifiers.
I’ve heard Wyred4Sound class D amps that sounded very good, maybe one of the best bang for the buck amps out there and a Wadia combo driving Vandersteens that sounded awesome. Both high power per pound values. Hey remember good old Bob Carver. He could make a 500 watt class G amp weighing about 15 pounds and sell it for under $1000 😂 (give or take) I love the guy, he made thousands off me in the 80’s
I have a VAC PA 80 80 tube amp that weights 70lbs and a class D amp that weighs 52 lbs
Listening pleasure per pound is very good!
I won't even mension how heavy my sub is!!
Glad three people got on here to post Nelson Pass' thoughts on the matter.  +1, +1, +1.
Do you like your current amp the JC1?  Are you keeping it?  If yes, buy the Anthem.  If not, then why change horses?  Ie, buy the Parasound JC5.  I have the Parasound C2 pre and love it.  I'm now using a DAC Maraschino 60 volt amp, beats my 50 to 70 lb hi current amps in every way.
lordrootman:  Now you have me intrigued.  I bought the Parasound A21 because I thought it was just beautiful with the top panel removed (specs were good too, but it was the looks that got me).  Now I have to check out that Anthem STR you are drooling over!
Thanks everyone for inputs 
I learn a lot
so is not always about the weight

Excellent. In return for putting up with the ribbing here's more good solid info than you ever dreamed there was on this subject. Or so I humbly submit, etc, etc.

Mass matters. Don't take my word for it. Put a phone book, dive weight, bag of sugar, anything heavy on top of a CD player, DAC, preamp, whatever. You will hear a difference. Or in case you don't, even better, you can now save yourself a ton of time and money from now on just buy cheap and good looking.

But probably you will notice the sound did change, the bass got fuller, and if it was something soft like the sugar then it also got fuller with warmth but if it was solid like a rock then it got deeper and tighter. And not just the bass but the midrange, and treble is more dynamic.

So mass does matter. Stiffness does matter. Damping matters. Just not at all in the way you were asking, which is why you got so much static. Of course weight does not matter, per se. To be totally honest nothing matters but how it sounds. Take any design, any technology, does not matter. There's tube amps that are tight and etched and grainy and there's solid state amps that are full and liquid and warm. None of these tech things you are so focused on means anything. Only how it sounds. Go and listen. You will see.

I don’t really need more power than A21+ for my current set up just to cover future upgrade 

No one needs more than about 30 to 60 tube watts, or about 100 solid state watts. No one. If you think you do all that means is you made a mistake somewhere. Most likely you got sucked into some hard to drive speakers. Happens a lot.

Number One with a bullet thing to keep asking yourself when shopping for amps: If the first watt isn't any good, why in the world would you want 200 more of them? 

The preamp looks amazing though for 4K

If you say so. What looks amazing to me for $4k is the Raven integrated. For $4k you get a preamp, and amp, with all the power you need. 30W. PLUS with that you do not need another power cord, interconnect, fuse, cones, shelf, or any of the other stuff which if you cut corners on will insure you never, ever get the performance from that preamp and amp that you paid so dearly for.

My guess would be, just to give you some idea, you are looking at well over $10k in separates to match the performance you will hear with the Raven Nighthawk or Osprey. Well over.
@millercarbon says,
" Mass matters."
The designer of my new amplifiers, SMc Audio, agrees and added their new "Gravity Base" to each of my new monoblocks.  The Gravity Base is basically a heavy brass plinth that anchors key components within the amplifier and serves as the base.  They proclaim the difference is not subtle.

It’s like cooking. Things such as transformers, caps, transistors ... are like ingredients. They establish an upper limits. And of course how good you are as a chef determines the final finished products.  Mr. Pass probably won't be able to do much if he could only use some tiny little transformers.  
The weight of an amp results from the philosophy of the designer. If the goal is to have an amp that will linearly increase its power into low impedance loads then it's likely to be heavy. In addition, if the designer prefers Class A bias then that will also add to the weight. For example, I have a Krell KSA 300S that provides 300 watts @ 8 ohms, 600 watts @ 4 ohms, and 1200 watts @ 2 ohms. Very few amplifiers will do this. There is also a automatic biasing feature that causes the amp to run in Class A mode up to high wattages. It weighs 185 lbs.

So why do I need all that power into low impedance loads? Because I run Thiel CS6 speakers that have low sensitivity (87db) and their impedance drops to below 3 ohms for parts of the audio band. This is a brutal load for an amplifier. For a speaker load like this the amplifier's capabilities will make a big difference in how the speakers sound.

Your Klipsch speakers are on the other end of the spectrum compared to my Thiels. They have 102db sensitivity which is very high. You would be fine with an 8 watt Single Ended Triode tube amp if you wanted to go that direction. Because your speakers are easy to drive you have a virtually unlimited selection of amplifiers.

If you had a bias toward tubes (pun intended) then you could go with any number of beautiful tube integrateds or separates. You don't need any more than 30 or 40 watts to shatter the windows unless you have a very big room.

If you are smitten by the appearance of gear then I have a word of warning. Don't look at the Line Magnetic LM-845 Premium integrated amp. It's necessary to see it in person to get the full effect (by the way it's really heavy). It's a little fat for your price range but you may sell the dog and take out a second mortgage to buy it. It wouldn't run my speakers but it's perfect for yours. The LM-845 may be the most beautiful piece of gear I've ever seen.
The McCormack DNA1 was my first real high end amp. Inside the box was this cheesy looking pointy nut screw thing. The manual called it a grounding spike and said try something like a coin under the spike. Looked silly and the pathetic but I tried it and sure enough it did tighten things up a bit. This was back early 90's. So Steve McCormack was an early adopter in the area of vibration control. 

That's really what is going on. Everything vibrates and mass tunes the vibrations. But not only mass. The same mass of lead, copper, iron, stainless steel, sugar, books, wood, carbon fiber, acrylic, will not sound the same. 

The thing is, where this comes into play with us and the OP question, this whole mass matters question is but one of many the designers and manufacturers have long since taken into account. One may do it like Steve all deliberate, another may do it by total disregard as not worth the time/money/effort. Whatever. Doesn't matter. Point is from our point of view all that matters is the result. There's just way too many different variables to think its even remotely possible we could look at something as silly as design and think we are able to figure out what will make the difference and what will not. Which is why we have to go and listen. 

But then, once we find the best by listening, then we use our knowledge of things like this to make it even better. Understanding not only mass matters, but stiffness, and damping- and those three are only the three that matter in the area of vibration control. Then there's the circuit design, which we generally have no control over (hardly anyone proficient enough to alter a circuit- note I said alter not merely upgrade parts quality in the same circuit which is a whole different thing). Then there's acoustics, and electricity. Which if you read mahgister he calls these his 3 embeddings. Whatever. Same general idea.

So even something as silly as "does amplifier weight matter?" turns out to have a serious side to it. Its just the silly aspect needs to be stomped to death, because its freaking rampant across the whole audiophile community. Everyone obsessed with arbitrary technical minutia like this when its a (near) total waste of time that could much better be spent listening and learning how this stuff actually sounds.

Post removed 
Possibly just above your price point, but have you considered a tube amp such as the Audion KT120? Should easily drive your Klipsch and include the toroidal transformers in 36 pounds (if weight is not a selling point for you) All Class A

If you are looking for SS I would highly recommend the FirstWatt SIT-3   

Both sound beautiful!!!!!!!
My single ended Dennis Had Firebottle amp puts out 12 to 17wpc and weighs a massive 15lbs. Sure, it seems like I should reinforce the floor for the thing, but somehow I get by fine...15lbs...if it was dropped on your head from 10 stories above I'd want it back as hey, who the hell is dropping my amp from 10 stories up? I hate that.
@dseltz thanks for the response my 2 channel set up is including 7.1.2 HT in family living room with kids so definitely no tube amp I will be interested to add tube preamp in future 
I really love the presentation of SS and tube preamp combo 
Looking from a prospective I think a manufacturer who will implement both correctly will win at the end of the day 
Lord...more weight not necessarily better for sound, reliability etc. Weight only comes into play for me if I have to move the thing around.
@millercarbon no one pay full MRSP 
you can get discount 15-30% off MRSP or 30-50% off on open box demo or used market 
I was able to get 25% discount on  my current Parasound A21+ and P6 new  

due to my current situation I’m not interested in tube amp or any integrated thanks though 
I've got 50 lbs. of 12 channels that allow me to do Whatever I wish.*S*

Y'all can keep your 2 chan backbusters....;)
My MC2250 weighed 80 lbs. It was a gift, so, Zero per pound. Until, moving it out of a low shelf, I got a torn meniscus in my knee, surgery, .... it turned out to be a darn expensive amp.