[darredon]

Are all power amplifier watt’s equal?

I’ve been debating with my friend that all power amplifiers watts can’t be equal, but then I’m no engineer and so I thought I would pose the question to my Audio circle community and see what you guys think.

Here’s the question, and maybe you guys have already answered this and if so please lead me to right thread, but recently my friend and I were looking at a McIntosh mc501 monoblock amp 500 watts $11,000, $6700 on craigslist, and a Emotiva XPA 2 monoblocks 500 watts $ 799 brand new. Can someone tell me why the difference in price? What’s the difference between one amplifier at 10 watts and another? Isn’t 10 watts 10 watts?   Can someone help me understand what makes one amplifier of equal watts better than another?

Thanks

Darredon

[TerryO]

Derredon,

Watts are watts!

How they measure them and what some of the other factors (distortion, harmonics and negative feedback) are, is a whole separate question.

McIntosh was, and still is, one of the very best engineered products in the USA...period. A Rolls-Royce and a Yugo are both automobiles with a lot of similarities (4 wheels, transmission, seats, doors and etc.) but that doesn't make them the same by any means.

Best Regards,
TerryO

[hmen]

To use another car analogy, two cars can both go 60 mph but how long does it take each car to get from 0 to 60? How bumpy do the two cars feel when they shift gears? How noisy is the engine when you accelerate? Can the car maintain a high speed for a long time without blowing out the engine?
Watts are only the measurement of one aspect of an amplifier's performance and a lot of people will tell you it's not the most important. At companies have different ways of measuring. Just because someone says they're giving you 500 watts doesn't mean that you're going to get a steady clean 500 watts at all times under all conditions. There are a lot of amps that cost considerably More than that McIntosh that produce less than 10 watts a channel.

[richidoo]

The sophistication of a high end audio amplifier is not in the power rating. It's in reducing distortion while delivering a gorgeous sound. Some rock star wannabe PA amps make 1000W for $400 brand new! Good enough for that application where low price and high SPLs are all that matter to their high school student customers. In high end audio, the pickiest nutcase audiophile wants absolute perfection on his violin recordings which don't even need 5W, but he'll pay anything if it makes him smile. It's a different design challenge than watts per dollar. High end amp designers are therefore a very special breed themselves, more like electronic fine artists. You might like to read some of Nelson Pass' articles to learn more about the subtleties of high end amplifier design. http://passlabs.com/articles.htm

This 32watt tube amp will set you back 130 large, and IMO it's worth every penny! Many high end audiophiles might say it is better than the MC501 - but only about 5% of the peak continuous power. It's a crazy hobby.
Rich

[whubbard]

More car stuff...

Two cars:
500 Horsepower each.

Are they the same?
Do they perform the same?

-West

[Barry_NJ]

Well first of all the Emotiva XPA-2 is a 2 channel amp not a Mono-Block and it puts out 250 watts/channel into 8 ohms and 500 watts/channel into 4 ohms. The Emotiva Mono-Block is the XPA-1 and they are 500 watts into 8 ohms, and 1000 watts into 4 ohms, and cost $999 each. The McIntosh amp puts the same 500 watts into 4, 8, or 16 ohms and uses a transformer to couple the amp to the speakers. Amps can use different topologies, A, A/B, B, D, H, etc. There's more to an amp than just watts. Also Watts = Current x Voltage, some amps deliver more of one over the other to produce the same wattage.

[darredon]

Thanks for the clarity on the issue, I knew I could count on you guys to make it clear. I like the car analogy. I can follow that logic. I guess it’s all in the parts and engineering.

I just saw this company Emotiva offering 500 watts monoblocks at $ 799 and I wondered can the high end amps sound that much better? That’s a lot of power.


Darredon

[darredon]

My bad your right Barry_NJ the Emotiva XPA-2 is a 2 channel amp not a Mono-Block

[Barry_NJ]

I haven't heard an Emotiva amp yet, but I'd really like to.

[burn_unit]

A watt (actually delivered) is a watt (actually delivered,) but that fact is largely beside the point.

[avahifi]

Another way to look at it is to think of 20 pounds of extremely well prepared prime ribs on one side of a balance scale and 20 pounds of White Castle sliders on the other side, soggy onions and buns and all.  One could say that since the scale balances both sides are the same. Some others might disagree.

Regards,

Frank Van Alstine

Or to look at it even futher, is that 20 pounds of prime ribs the same after it has been reheated in a microwave oven?  Still the same amount of meat and seasoning.

[Niteshade]

Do not get a question regarding power confused with delivery performance. One watt is one watt, whether it's an amplifier or a laser's output. This cannot be disputed: 1W RMS=1W RMS. 

The question of power often masks what the questioner really wants to know: How is that power delivered?

This thread should be based around the observations of delivery quality and not wattage.

Lasers: Don't get any funny ideas about cranking up your laser pointer!  There's plenty of U-Tube videos on that stuff...

[darredon]

I like both AVAHIFI and NIGHTSHADE'S feedback. As for the ribs I like them both ways. In fact sometimes there even better the day after. 

Okay so let’s run with this idea of delivered quality. Lets say the only thing I  switch in my system is a high end amplifier (big dollars $$$$), and a mid-fi amp (mid dollars $$), both claim to put our 500 watts. I pulled the specs on both, I don’t understand them however maybe some of you do. The question is would I hear a difference in quality? The second question is if there is a difference does the cost difference really warrant the price difference? I understand that’s a matter of opinion based on your own criteria for your system, but really do I get that much more quality if I buy the $$$$ over the $$? 



$$ amplifier

Rated Power Output: (One Channel Driven @ 1Khz, 115VAC/ 60HZ supply, THD noted)
500 Watts into 8 Ohms (1%THD)
1000 Watts into 4 Ohms (1%THD)
Frequency Response:
20-20Khz: +/-0.1dB
10-100Khz: +1/-3dB
Total Harmonic Distortion (THD): (80kHz measurement bandwidth)
<0.040%
Signal-to-Noise Ratio: >100dB, Unweighted (Full Output Reference)
DC Offset: <10mV
Crosstalk: >80dB
Damping Factor: Approximately 200 into 8 Ohms
Input Sensitivity Range (Gain):
34.5dB
Input Impedance :
(RC A Input): 20K Ohm
(Balanced Input): 18K Ohm
External Trigger Input: 5~12 VDC, center tip of 3.5mm jack is positive
Clearance for ventilation (Back): Minimum 2” / 50 mm
Electrical Power Requirement: 1000 watts @ 115VAC when driven into 8 Ohms
Electrical Power Consumption: 4 Watts (Standby) and 90 Watts (Idle)
Raw Weight: 76lbs/ 34.5kg
Shipping Weight: 89.2lbs / 40.5kg
Dimensions:
623mm W x 586mm H x 298mm D



$$$$ amplifier

FREQUENCY RESPONSE
+0, -0.25dB from 20Hz to 20kHz
+0, -3dB from 10Hz to 100kHz
TOTAL HARMONIC DISTORTION
0.005% maximum at any level from 250mW to rated power output.
INTERMODULATION DISTORTION
SMPTE 0.005% maximum if instantaneous peak output does not exceed twice the output rating.
A-WEIGHTED SIGNAL-TO-NOISE RATIO
Unbalanced and Balanced: 97dB (124dB below rated output)
RMS POWER OUTPUT
500W minimum sine wave continuous average power output from 20Hz to 20kHz.
INPUT IMPEDANCE
10,000 ohms (unbalanced)
20,000 ohms (balanced)
INPUT SENSITIVITY
2.1 Volts unbalanced, 4.2 Volts balanced
WIDE BAND DAMPING FACTOR
100 @ 8 ohms
DYNAMIC HEADROOM
1.8dB
RATED POWER BAND
20Hz to 20kHz
POWER GUARD®
Clipping is prevented and THD does not exceed 2% with up to 14dB overdrive at 1kHz.
POWER REQUIREMENTS
120V 50/60Hz, 6.6A
OVERALL DIMENSIONS (H x W x D)
9-7/16” (22.86cm) x 17-1/2” (44.45cm) x 14-13/16” (37.62cm) including front
panel and knobs.
WEIGHT
91.5 lbs. (41.6 kg) net
105.5 lbs. (48 kg) in shipping carton

[martyo]

The only piece I can take away from those spec's is that one amp has current limiting circuitry. In my experience, sonically speaking, that is not a good thing.

[Glen B]

IMO the more expensive amplifier is likely the excel over the cheaper amp in subtleties such as timbral accuracy, lower levels of grain, better low frequency performance, greater transparency, greater detail, better soundstaging and image placement, etc.  Whether or not an individual is willing to spend the extra money depends on what they value in their music playback and whether they can even hear the differences.  I own/have owned both modestly priced and kilobuck high end equipment.  Both types have sounded pretty good, but I find the more expensive stuff to just have that extra little bit of refinement that I value. 

[TerryO]

I like both AVAHIFI and NIGHTSHADE'S feedback. As for the ribs I like them both ways. In fact sometimes there even better the day after. 

Okay so let’s run with this idea of delivered quality. Lets say the only thing I  switch in my system is a high end amplifier (big dollars $$$$), and a mid-fi amp (mid dollars $$), both claim to put our 500 watts. I pulled the specs on both, I don’t understand them however maybe some of you do. The question is would I hear a difference in quality? The second question is if there is a difference does the cost difference really warrant the price difference? I understand that’s a matter of opinion based on your own criteria for your system, but really do I get that much more quality if I buy the $$$$ over the $$?  

Darrendon,
You seem to want an answer, so the answer is: yes and no!

Question #1.
In your system you would not hear a difference. However, in my system I most certainly would.

Question #2.
In your system the cost difference does not warrant the price difference (whatever that means).
But, in my system the cost difference does warrant the price difference!

Now you have some answers that will certainly simplify matters.

If it doesn't, then perhaps your questions were altogether too vague and generalized, not to mention that they call for a conclusion related entirely to personal preferences and taste. Please note that we haven't even addressed what constitutes the rest of your system, your budget, your listening space and the type of music that you'll be playing.

Best Regards,
TerryO

[Bob in St. Louis]

"but really do I get that much more quality if I buy the $$$$ over the $$?"

I think you're talking about the point of diminishing returns, which of course is highly dependant on MANY variables, most of which haven't been discussed yet. That "point" is different for every person, in every room, and needless to say, every budget.

Here's another car thing for ya;
A large farm tractor maybe 1000 horsepower, just the same as a Lamborghini. Cost wise, they're probably about the same.
"What's your style"?    aa

Bob

[BobM]

I think he's got it now, don't you? Well, maybe a few more ...

Ferrari vs Hyundai - both will get you there
Dress Shoes vs Sneakers: both fit on your feet
Brooklyn Bridge vs Manhattan Bridge - both get you across the river
Ski's vs Snowboard - both get you downhill
Tap vs Evian - both are water
Palm vs Blackberry vs I-phone - all make calls
Pen vs Pencil - both write
  vs  aa - both are smiley's
LCD vs Plasma vs Cathode Ray - all will let you watch the game
PC vs Mac - both let you view your e-mail
Stereophile vs Absolute Sound - both review equipment
Angelina Jolie vs George Clooney - both are hot celebs

So, if you think you can find the differences in these choices then you should be able to describe the differences between mass market vs high end components. Different levels of quality, different times to use them, different preferences by the consumer, different nuances, different practical usage, different price points, different type of consumer, different architecture, different prestige factor, different viewpoint, etc.

Bob

[muralman1]

Using cars, my Subaru Sti has a four cylinder engine rated at 305 horse power. A 60's muscle car has 8 cylinders and (generically speaking) around 450 horse power. On acceleration they are quite comparable. Efficiency plays some part in the power similarity.

My class D H2O is rated at 250 watts. The Pass Labs X-600.5 is what it says. Both can drive my 1 ohm speaker. with the H2O seemingly more dynamic. The reason for this is the H2O is much more efficient. 95% of the power is consumed making music. The Pass amp is wasting 250 watts just like the muscle car is wasting horse power as it spins and burns tires.

[IronLion]

The Pass amp is wasting 250 watts just like the muscle car is wasting horse power as it spins and burns tires.

Isn't the Pass amp just using more power to generate that 250wpc?