Overrated vs CEA Car Amplifier Test | True Wattage Revealed!

See the difference between a Quality, CEA-2006 amplifier and an overrated "crap" amplifier. Using our test car, we use an oscilloscope to measure the true RMS power ratings of two amps, one of which is CEA compliant and the other is not. This demonstration shows that there are sometimes huge differences between the ratings that the manufacturer gives the amplifier and what the amp will actually produce without clipping the signal. The goal is to use equipment that will not clip or distort the audio signal, as clipping can quickly damage your audio gear.

Quality Amp: Kicker ZX300.1
-- 150 watts x 1 chan. (4 ohms)
-- 300 watts x 1 chan. (2 ohms)

Overrated Amp: What amp do you think it was?
-- 250 watts x 1 chan. (4 ohms)
-- 500* watts x 1 chan. (2 ohms)
NOTE: The manufacturer does not state a RMS rating at 2 ohm, but in theory it should be 500 whats... assuming that it can do 250W @ 4 ohm... :)

[SonicElectronix]

I'm glad you asked. Before filming the video we called Fluke to confirm our settings for the video. The Vrms setting detects the output of the amplifier and auto-calculates the RMS power output of the amp in real time.

[SonicElectronix]

We used the Vrms meter setting, which detects the real time RMS output from the amp. (Confirmed by Fluke).

[SonicElectronix]

No problem! REMEMBER, that is just an estimation formula, it is used to help you figure out if the amp you want is untrue to it's ratings. You will see on high quality amps that your formula will give you higher power ratings than what they advertise, which is good. Use it as a tool to help you, don't use it as a final decision maker. :)

[JaMarvelousjmar]

This video should have gone viral in the car audio industry. Allen touched on so many basis. Great job

[SonicElectronix]

No and No. To get a rough estimate as to how much power an amplifier outputs at it's lowest impedance (ohm rating), just use this formula. Multiply 14.4V by the combined amperage of the fuses on the amplifier, just add the fuse ratings together, and then multiply by .8 for class D amps or .6 for A/B class amps. For example, 14.4 x 30A x 0.8 = 345 Watts (estimated) at 2 ohms. Use this to help you find out if amplifier output what they say they do.

[SonicElectronix]

While its not quite 11.9v, Crossfire does rate their amps at 12.5v. They don't submit their amps to be CEA-2006 compliant, but in our experience they put out true power to their ratings.

[Prynse]

Thank you so much Sonic Electronix, yall have taught me so much, now I will never ever have problems with anyone trying to sell me a weak amp or weak subs

[SonicElectronix]

The NVX 800.4 is a top notch amplifier so far, no known issues and it outputs tons of clean power at true rated values.

[SonicElectronix]

If we are looking strictly at power ratings, you should be fine with any CEA compliant amp. The more expensive CEA compliant amps usually have other features that raise the price (bigger heatsinks, more expensive materials, more tuning options, lights, etc..)

[cj]

Superb video. Explains how the cheaper amps can be really deceptive with their ratings. Definitely going for a CEA compliant amp now.

[the_Boost_within]

THANK YOU!!! i spend (waste) so much time trying to explain to people that low quality amps are just that, but all they seem to believe is what the box says. It's ridiculous. My ears hear the difference that the speakers tell. Same with building the right size box.

[ricemilk]

I have so much respect for this video... i have for many years been telling people about quality before power! People wonder why real tube amps are often rated @ 20watts per channel yet can cost thousands, but still yet would rather go & buy 200watts instead!

[SonicElectronix]

No, that is an entirely different situation. Those amplifiers are a breed of their own and have power supplies that are regulated to provide constant output at any impedance. They are quite good.

[SonicElectronix]

Gain adjustment is a very difficult thing to do. Your headunit itself could be clipping your signal, try not to turn it up past 75% or so. The input voltage on the amp (the gain) should match the output voltage of the line out converter. If they match, and you are not happy with your system, you will need to upgrade to a more powerful sound processor or headunit.

[SonicElectronix]

Remember, wiring in series is used to INCREASE the Ohm load and parallel is used to DECREASE the Ohm load. A single Dual 4 Ohm subwoofer wires to a 2 ohm load, so you will need a 2 ohm stable amplifier at the RMS wattage of the subwoofer.

[SonicElectronix]

Incorrect gain, which results in distortion and then overheating of a woofer is the #1 reason for subwoofer deaths. The gain control is VERY misunderstood. Gain control is meant to match the output voltage of the device (radio) to the input voltage of the amplifier. Take a .25V audio signal and turn your gain to max and the amp will amplify that signal so much it begins clipping and distorting which ='s death to woofers. Low wattage itself wont ruin a sub ever, turning the gain up will.

[SonicElectronix]

The efficiency for a Class D amp is, on average, suppose to be 80%(0.8). Class A/B amps on average are 60% (0.6). However, there is a Class D amp that is 90%(0.9) efficient, so if the efficiency rating is given, just plug that into the formula. For weird amplifiers, like Class H or Class BD, just stick with 0.8 unless they list otherwise because most of them are based on Class D technology anyway. Cheap Class D amplifiers can be 60% or less efficient, that is why the formula just a helping tool.

[SonicElectronix]

That formula will get you an estimated total RMS wattage at the amplifiers lowest impedance. If you use the formula on a 4-channel amplifier, divide your final number by 4 to get the estimate RMS of each individual channel.

[milfhunterX]

Back in 04 I purchased a RF power series amp model 330 for $330. paired with my 3 12" kicker cvr's they were ridiculously loud. A buddy had a similar settup but using a 2000 watt planet audio and my 330 RMS walked all over his amp. Those first Power Series amps were serious and were $1 per watt, but were bullet proof; mine is still in service.

[thekilomike]

As someone said; the scope is reading VOLTS rms. You need to use a dummy load for the output and clarify what you are measuring.