The short answer - IT DEPENDS… When there aren’t a lot of regulations on how companies portray their specs and measurements, we have to learn how to compare multiple spec lists accurately.
Our in-house audiophile, Mitchell, gives us the long answer on our YouTube channel:
To really get into the nitty gritty of how companies provide their spec list and measurements, read on for Mitchell’s A-B-C product comparison.
In most industries, brands utilize specs to grab consumers’ attention rather than portray the numbers you really need to care about. These specs - even when inaccurate or not useful - are used to market and vie for the top spot among the competition. What you need to know is:
Wattage = THD (Total Harmonic Distortion) + N (Noise)
This measurement is essentially the amount of distortion or imperfections the amplifier is producing in comparison to the audio. Common measurement levels are 0.05%, 0.08%, 0.1%, and 1.0%.
The FDP rating system is meant to give a more accurate representation of wattage in real-world situations. FDP is measured on ALL Channels Driven simultaneously, over Full Frequency Response (20Hz - 20KHz) bandwidth, and at Rated Distortion (typically 0.08%). This is a far more accurate representation of wattage compared to the Federal Trade Commission (FTC) minimum requirement of 8 Ohm, 1 Channel Driven, Limited Frequency Response (1KHz), and any level of distortion.
Begin by asking yourself the following questions:
When listening to music or movies, you are listening to full frequency response, so any limited frequency response is inaccurate and has no real-world use for you.
The term amplifier and receiver tend to be used interchangeably, but keep in mind that - all receivers are amplifiers, but not all amplifiers are receivers.
On an integrated stereo amplifier (control and connection hub for an audio-only listening experience) you want the wattage to be measured out of both channels simultaneously, so either “All Ch. Driven” or “2 Ch. Driven”.
On a home theater receiver (control and connection hub for audio AND video needs of a home theater system) you want “All Ch. Driven” simultaneously. If “2 Ch. Driven” or “1 Ch. Driven” is the chosen measurement, expect real power to be substantially lower than claimed, because once you spread that power over all of the channels (as it will be used), that measurement becomes much lower.
In short, DF is how accurate the frequency response is throughout the frequency range, as well as how much control the amp has over drivers in the speaker.
Any DF above 100 will provide a very accurate frequency response, and in a real-world test it would likely be hard to tell any improvement above that, even with a DF factor of 300 or higher. However, a DF of 10 causes up to a 3 decibel drop in low frequencies, which is very noticeable. Avoid a DF below 50.
Now that you know what questions to ask yourself, let’s compare and contrast 3 receivers from 3 different companies to determine which 7 Channel Receiver has more power.
At first glance it seems to be that B has the most power. However, both A and B do not measure “All Channels Drive” simultaneously. Meaning, we cannot get a realistic idea of true power on A and B.
What we do know is that all of the receivers measure stereo performance.
A is 100 watts (FFR 20Hz - 20KHz, 8 Ohms, THD 0.08%), B is 120 watts (same measurements as A), and C is 110 (same measurements except a lower THD of 0.05%). Because C is rated at a lower THD, we know that if it was measured at THD 0.08%, it would have a higher power rating, but we do not know how much higher it would be.
Thus, we can say B is more powerful than A, but we do not know about C.
So let's compare dynamic power - the maximum amount of power the amplifier can produce over a small period of time, rather than continuously.
A does not have dynamic power measured. B has it rated at 250 Watts at 3 Ohms, 220 Watts at 4 Ohms, and 130 Watts at 8 Ohms. C is rated at 243 watts at 4 Ohms and 137 Watts at 8 Ohms.
We can compare both 4 Ohm and 8 Ohm ratings - letting us know C is the most powerful amplifier.
Even though C is the most powerful amplifier, it is rated at only 60 Watts (FDP measurement) vs. the claimed 100 Watts for A and 120 for B.
So, you can see why these measurements are complicated and can be deceiving to your real-life measurement and application of the “most powerful amplifier.”
This sort of marketing is everywhere in Audio/Video. So, now that we’ve tackled the deceptive part of the industry equipment specs, you can understand the value of measurements applied to a real-world listening experience.
Most individuals use between 10 Watts and 20 Watts - any more and it's just headroom and more “horsepower.” That doesn’t mean that power cannot be used. In most cases, more power does mean more control over the speaker.
Think of it like replacing the engine in a Toyota with one from a Ferrari… the Toyota engine still did its job, but every aspect of the car changes when you make that adjustment. Even at lower speeds, the car would be more agile, lively, and have an advantage at higher speeds.
The same thing happens with a speaker. Higher Quality Amplifier = Better Engine.
This means that nearly every aspect of the audio will improve - better low frequencies, clearer highs, and more powerful mids.
So to conclude Mediahead Mythbusters 2… Does More Watts = A Better Amplifier? YES! As long as you know how to read the measurements to determine accurate vs. inaccurate Wattage claims.