I am in the market for a stand mixer and the manufacturers often tout that their mixer is (say) 550 watts (or whatever). Presumably this means it is more powerful than machines with a lower wattage. But then a $2000 Hobart stand mixer (meant for professional kitchens and waaay past my needs) is 350 watts and better in nearly every way.
I have seen repeatedly that using wattage as a measure for these machines is meaningless. Maybe it is meaningless for other machines too but going with mixers since it is what I am looking at.
I believe that but why? What is the trick the manufacturers are pulling on us here?
Well, first off they often lie or mislead with regards to the watt rating. But besides that, a good mixer (or whatever) is about far more than the power rating of its motor. A well-engineered drivetrain that can deliver that power reliably to the mixing bits, good quality materials that will stand up to the use and abuse it will see, well-thought-out features that are useful instead of gimmicky, etc. The problem with most crappy kitchen appliances isn’t that they don’t have enough power, but that they’re poorly made.
With stand mixers in particular, it’s the torque that matters, not the power. The few times you need the mixer head to be going very quickly, it’s for light items like whipping cream which basically every mixer can do acceptable. Where a mixer really shines is very low speed mixing of dense materials like kneading bread doughs. This doesn’t require much power but it requires a lot of torque.
The trick is that a lot of naive buyers are impressed by a high wattage rating, and think that makes it better. And it’s a lot cheaper to put a higher-powered motor into a mixer than to make other quality improvements.
Same problem with LED lights. It’s really easy to make an inefficient LED that outputs a lot of heat, it’s easy to make a motor that uses a lot of watts. All things equal more watts is better, but things are rarely equal.
The same escalation is going on all across the domestic appliance market. Vacuum cleaners are a prime example; they have been getting ever more ‘powerful’ and noisy and more expensive to buy and run, with no corresponding improvement in cleaning power.
This is an old home and car audio advertising trick too.
“This subwoofer handles 600 watts of face-melting power!”
or: “This six-channel amp/receiver puts out an astonishing 1000 watts per channel!”.
Um,no. In this instance, the advertisers aren’t quoting the appliance’s actual ability/performance (measured as RMS, or continuous power handling), they are tossing out a meaningless stat: very brief peaks of power that the component CAN handle.
Always look for RMS power instead of peak handling. You’d be amazed how different the actual figures are.
Also, protip: The gain is NOT a volume knob. It’s for balancing different groups of loudspeakers that are amplifier powered.
It’s a deceptive sales tactic that’s been going on forever for lots of things. I remember when PCs were judged by how many MHz (or GHz) the processor ran at. And engine horsepower is still used as a measure for how “fast” or powerful a vehicle is.
Sorry for the hijack, but I have always hated the term “RMS power.” Yea, I know what it means. But it really should be called “average power” and not “RMS power.” The problem with the latter is that it could be interpreted as taking the root-mean-sum of the power waveform, which (AFAIK) is never done. When it comes to power, engineering folks talk about average power and peak power, and EE’s will further talk about real power, reactive power, and apparent power. “RMS power” is not in their vocabulary.
Product quality is a big issue for all of us. Rather than rely on specs and other information provided by the manufacturer, I try to find out as much information about a product as possible from 3rd party sources. I subscribe to Consumer Reports and have used their critiques many times to make purchasing decisions. I also Google product names beginning with the words, “Issues with _____”.
In your case, as soon as I saw the name “Hobart”, my thought was, “Buy it!” They have a long track record of great mixers.
Quora answers this pretty well, here wrt to the difference between RMS(Root Mean Square) and Average power. For back of the napkin calculations I was taught RMS power=Pk power x .7071, and Avg power =Pk x.637. This doesn’t take into consideration phase shifts and assumes perfect sine waves but it works well enough for most purposes.
When I was stereo shopping I came across this quite often where a cheap amp might proclaim 100W/ch and a far more expensive one “only” 30 but if you looked at the fine print it was 100W pk to pk at 1000 Hz and 10% total harmonic distortion. The expensive amp was 30 W continuous 15-20000 Hz at .01 THD. So what does all that blah blah mean to people who don’t have an electronics background? It looks like the cheap amp kicks the expensive one’s ass. But if you compare the amps the same way that 100W amp is 50 W Pk , 50 x .637 to get Average(or continuous) pwr and it’s now down to roughly 31 W.
Not done yet, though. The cheap amp only pumped out that much power while clipping the sine wave at one frequency to the point it’s pretty much noise. The expensive amp is producing clean audio across the audio spectrum. So to match the same THD number on the cheap amp you have to turn the volume waaay down (assuming the components are good enough), so in the end your 100 W amp is more like 10W, maybe 15 at best to match the expensive one.
Watts can be useful but as alluded to above it’s like buying a car based on hp alone. 500 Hp and a cardboard driveshaft is an apt analogy.
Well, SOME of us EE’s in the distant past have used the term RMS just because the slightly educated consumer adopted it as a “honest” (not peak) measure of power and were constantly asked by friends to help them evaluate their audio decisions.
Not saying (admitting) I did that, of course.
The Quora discussion is talking about RMS voltage and RMS current, both of which are valid concepts. They’re not talking about “RMS power.”
It is perfectly valid to talk about average voltage, RMS voltage, and peak voltage. It is also perfectly valid to talk about average current, RMS current, and peak current. But when it comes to power, we are pretty much limited to discussing average power and peak power. RMS voltage and RMS current can be used to calculate average apparent power, and if you also measure the phase angle you can calculate average real power. There’s no such thing as “RMS power.” As mentioned previously, when someone says “RMS power,” what they really mean is average power.
I am guessing the whole “RMS power” thing came about when someone said, “We measured the output voltage using an RMS voltmeter and the output current using an RMS ammeter. We then multiplied the two numbers and called it ‘RMS power.’”
There are a couple things wrong with this:
They are measuring apparent power, not real power. The real power delivered to the speaker will be less than the value they calculate.
They are measuring average power. it was a mistake to call it “RMS power.”
Not, disagreeing with you, just giving MHO as to why RMS was used.
I certainly agree with you that RMS was wrong but was it a mistake? Possibly.
Using the term “average power” to the layman might give them the impression that you are referring to the output of the amplifier at half volume.
In the 70’s and 80’s most “sensational” manufacturers were using terms like peak output power while the more responsible ones were trying to differentiate their products as having a cleaner output at the units upper operating level.
Yes, the RMS term was used incorrectly but it turned out to be a smaller lie the “Peak”
The really crazy thing was that just specifying power outage whether it was peak, RMS, or average with no reference to the total harmonic distortion at that given output was basically telling the customer how loud they could go but not how distorted (crappy) the output would be. Some manufacturers stated THD. By itself not meaningful but when stated at a reference output level it provided some additional information about the integrity of the amp.
Bread dough and stiff cookie dough are hard on poor-quality mixers. Getting a mixer that’s popular with people who make a lot of bread and big batches of cookies is a better measure than the watts.