I work for an electronics company that spends month dreaming up specifications to describe our products. We do it because it helps people get into the right ballpark - but then it's important to understand the whole picture. For musical equipment, I think this is much more the case. For my living room stereo, I want very low distortion because I want to re-create Carol Kaye's sound in my home. For my amp, I have all sorts of knobs and buttons plus it's own natural distortion because I'm looking to create - not recreate - a sound. So are watts a good or bad measure or an amp - neither, they are a pointer to help you narrow the choices down - but never a substitute for the old fashioned plug it in and see how it sounds with the rest of your equipment.
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Watts; the worst measurement unit ever for amp output?
- Thread starter nukes_da_bass
- Start date
Worst unit of power? Read this link, so you'll get a little background for this concept. James Watt was alive from 1736-1819- amplifiers hadn't even been conceived of.
https://en.wikipedia.org/wiki/Watt
Power and SPL at specific distances can't be a standard because too many variables are involved.
"Watts" never enter the picture anywhere in this whole business from beginning to end. They are rather a measurement of heat....heat that the speakers voice coil must get rid of somehow without burning itself up.
Well, there you go making my point even better than i could. Watts are a terrible rating system for amplifiers.
If i buy a heater or a stove i will look for a unit which measures heat
It's a measurement of power which causes both the kinetic drive of the speaker and the thermal losses. You are using an electronic amplifier, Watts are a perfect unit of measurement.
Wattage ratings are also pretty easy to provide. It's already a standard.
Using what cabinet? Using what signal source? How is the amplifier set? You'd be looking at more variables to provide a similar result, a number. A number which is just as meaningless as watts if the user doesn't understand what is going on.
The Watt can be calculated using P=IE, but it's defined as 1 Joule/second, or 1 Newton-Meter/second. The link I posted has more info.
Use computer programming notation:
P=I^2*R
And thank you Bassman1958 for the real definition of a Watt.
The amplifier section of this forum is amazing! I lack certainly the education and probably the intelligence of many of you. However, 30 years of practical experience owning and playing through Bass amps has shown me unequivocally that amplifiers that have the same theoretical wattage rating are far from equal.
Eventually I started to learn enough that amplifiers the double bass guys use on jazz gigs probably aren't going to cut it on a metal gig regardless of their wattage rating.
All amps are not created equal. At best, from practical experience, the wattage output rating of an amplifier is a base guideline starting point. That's all I've ever been trying to say.
Eventually I started to learn enough that amplifiers the double bass guys use on jazz gigs probably aren't going to cut it on a metal gig regardless of their wattage rating.
All amps are not created equal. At best, from practical experience, the wattage output rating of an amplifier is a base guideline starting point. That's all I've ever been trying to say.
If you dial the tube amp back to completely clean it will make similar loudness with similar RMS voltage as the SS amp. James Watt can rest easy.
True, but what does that tell you? Then all we are doing is replacing one non standard unit of measurement with another non standard unit of measurement. You just have to accept that there is more to "perceived" volume of an amplifier than a simple wattage rating. There are a lot of elements to an amplifier design that affect the perceived volume of the amp, not to mention the myriad of different ways a manufacturer can use to determine the power rating of their amps.
I walked past that statue nearly every day for the past four years, any caption I gave to that place would probably get me hit by the ban hammer
Hopkins
Commercial User
They state SPL at 1 meter, in most cases. This is because the room (or lack of) has everything to do with the SPL at greater distances. Also, the cabinet's dispersion pattern makes a huge difference- open-back, sealed and vented all have very different dispersion characteristics.
There's too much happening to be able to make a standard when using different speakers. Some amps react to the speaker more than others, some amps have a flatter response, some have peaks in different places and some just roll off the highs and lows with a smooth mid-range. Then, this is influenced by the room, the number of people, your hearing (human hearing is unique from one person to others), etc. Then, we need to consider environmental factors like temperature and humidity- denser air conducts sound better.
Watts are fine, easy to calculate for complex loads and non-sinusoidal signals. I share the OP's frustration with MI power amp ratings though. It may well be that the Eden was delivering its advertised power. The boogie on the other hand was delivering - well, a whole lot more.
For those who have posted the formulas to calculate power as measured in Watts, I would like to point out that it is as simple as the basic math involved for steady state conditions.
It becomes a little more complicated when the signal is a sine wave, yet not beyond basic high school algebra.
But what about when the signal is a complex non-linear waveform, which also contains transient voltage peaks, and is dissipated in a reactive load?
We are now measuring all the previously mentioned factors in the time domain as well.
This complicates the math, and is where the simple formulas presented here do not account for what is actually being measured.
I am not so confident in my math skills as Codger is in his, so I would not even try to do it.
That's why as far as selecting an amplifier to plug a bass into, and play with a band, in a room, you really don't need to know the precise wattage to select an appropriate output power rating for a particular application. You should have a rough idea if 20, 100, or 200 would work. If the manufacturer has been conservative, or over rated by some factor, they should still be close enough that what you thought was a 100 Watt amp does not turn out to be only a 40 Watt amp, (I hope).
It becomes a little more complicated when the signal is a sine wave, yet not beyond basic high school algebra.
But what about when the signal is a complex non-linear waveform, which also contains transient voltage peaks, and is dissipated in a reactive load?
We are now measuring all the previously mentioned factors in the time domain as well.
This complicates the math, and is where the simple formulas presented here do not account for what is actually being measured.
I am not so confident in my math skills as Codger is in his, so I would not even try to do it.
That's why as far as selecting an amplifier to plug a bass into, and play with a band, in a room, you really don't need to know the precise wattage to select an appropriate output power rating for a particular application. You should have a rough idea if 20, 100, or 200 would work. If the manufacturer has been conservative, or over rated by some factor, they should still be close enough that what you thought was a 100 Watt amp does not turn out to be only a 40 Watt amp, (I hope).
Maybe it would help to have a calibrated "standard" speaker to run the spl tests with. After all a calibrated (to some standard) microphone is an essential part of all spl measuring devices.
Personally, I always think the answer is try it and use what ever works for you. The amps I was able to try first seemed to stay in my stable a lot longer than the ones I bought (on the internet) based on manufacturer's spec, advertising hype, or flavor of the month; those were flipped pretty quickly.
It seems like my tastes in my bass tones rarely match the "norm" (whatever that is).
Personally, I always think the answer is try it and use what ever works for you. The amps I was able to try first seemed to stay in my stable a lot longer than the ones I bought (on the internet) based on manufacturer's spec, advertising hype, or flavor of the month; those were flipped pretty quickly.
It seems like my tastes in my bass tones rarely match the "norm" (whatever that is).
