How To : Clamp Test an Amplifier for Wattage!!! (HD)
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- čas přidán 16. 10. 2012
- This is a High Definition video tutorial of how to clamp test an amplifier brought to you by Skar Audio. While the testing was done with Skar Audio products, this method can be used across all amplifiers to test for actual watts your speakers are seeing.
Multimeters and Clamp Meters to measure the currents needed can be bought at your local Lowes or Home Depot. The amplifier used in this video is a Skar Audio SK-1500.1D
Enjoy!
For more information on Skar Audio visit www.SkarAudio.com - Auta a dopravní prostředky
Correct! This is true when using a reactive load, such as a speaker. I use resistive loads and phasing is not an issue (but your comment is for the uploader, not me)
Love your videos williston saw your dyno on the 2000.1 that's one reason I bought skar
Mr. Williston.... we meet again. 8 years later.
damn I just subscribed to you last month and you been doing it 8 years!
Hi, correct me if I'm wrong but simply multiplying voltage and current together doesn't give Real Power (Watts), it gives Apparent Power (VA). You need to multiply volts by amps by power factor which is determined by measuring the phase difference between the current and voltage signals.
New to Skar but I am sold. I have the evl 12s with the 2000.1 amp and wiring kit from skar. I have seen the same amp dyno tested and it hit 2526 watts ran the way I have mine sit up. When I move to my jeep I will likely be going with 45 of the evl 12s. I love Skar and show my system to everyone at work with one and I beat the brakes of of there stuff. Thanks again you have a loyal life long customer now.
I'm building a set analog meters exactly like the SUPER high end pro audio amps still come with for my car that's going to mount... somewhere.... Don't know about that yet. but it'll give me a really good idea of how many watts a note is sustaining. Analogue is still king in this world!
Love my Skar Amp and 2 10s!!!!
I’ve seen DB drags that measure this way amps and volts. You aren’t allowed to go over certain watts during the competition but go for max DB’s
hi! I have two speakers 15'' 8 ohm.i would like to know how to find out how many watts are those speakers?thanks!
Do you have to have the speaker wires hooked up to a sub or could they just be hooked up to a oscop as well
Very useful if your amp has the capacity to go louder than your speaker.
On my meter(the red one)i have two i puts for red plug which does it go to one says 10adc the othe says Vma
Thanks Mr Deep Voice ;c]
So are you measuring ac amps or dc amps
An easier and cheaper way to get wattage is to measure ac voltage at the speaker terminals, multiply that voltage by itself, then divide by speaker impedance..... No need to buy a clamp meter. BUT, for either one of these methods, you will not be getting a very accurate measurement, because a speaker's load is reactive, and changes with the input signal. For true measurements you need a dummy load capable of the wattage you want to want to test, and an oscilloscope, or an amp dyno.
John Payne that doesn’t account for box rise or a variety of other factors, the only thing just testing ac voltage is good for is if your comparing different amps on the same sub- box setup
@@charliefrancis6438 thats what he meant by "speaker load changes with input signal(frequency)"
You could use speaker as dummy loud but you have to know impedance curve and play frequency where its at nominal impedance.
and what is the power supply output that looks pretty dang small, i say battery bank always to give the amp the max at full load, unless you test ac wall plug in amps
is it possible to extract 500 watts from your power supply? i think its only 300 watts
Could I use pink noise instead of a 40Hz test tone?
are these amps going to be sold as B stock now?
What did you have to turn the gain up so much?
will the amplifier see a load of the dmm?
what the name of that power supply
plz redo this video with a cam that focuses when aimed at meters settings.
Yea bro 500 watts of wattage bro
Hellz yea
and the sub too?
Isn't running the speaker at that power when it's not in an enclosure bad for it? And will putting the sub in an enclosure change the readings vs. free-air?
And usually there's a vent I'm the middle
The only way to properly figure power is by attaching a power resistor to the amplifier output, measuring the temperature at rest, and then after running, to determine how many calories were put into the load. From calories, one may compute watts. All of the calculations for power -- RMS and otherwise -- go out the window when an arbitrary non-sine waveform is used. For that matter, it would have been easier to measure the amperes going into the amp at 0Hz (DC) rather than an AC output value.
I know it's an old video but my I notice the amps stays relatively low, on my pioneer system my 800 watt amp goes up to about 24v but 20+amps, is this normal?
Yeah, it's normal for some amps to step up voltage less than others, you still get the same overall power. If this is the case though make sure you have speaker wire thick enough to handle the amperage.
I thought your amp generates more amps during a low voltage situation. Correct me if I'm wrong. Adding a spare battery would help no.
big fan of skar i plan to use your 8s in a build..thanks for the video
I need someone to explain to me what the numbers on my clamp meter and voltmeter represent.
I’m thinking the same thing. There’s so many dials on both meters. Which one is to be set on what? 🤔
GOOD VIDEO GUYS
I would like to know if a pyle that says it produces 80wX4 is true
I wouldn't trust anything printed by PYLE except their brand name. PYLE of shit, that's the most you can count on.
I would calibrate ur internal gyros , u were swaying like u were at a!a celine Dion concert
what if amp power is very low {3 to 6 wats}?
do u know that ur banner covers almost everything u are trying to show?
Man kevin, i love those zvx 12's specs. BL 41+ O_o... no biggie. only double what a sundown nightshade has. ughh cant wait till i get mine. SOON! i have over half the money saved. Hope to contact you soon.
Lol. You have been highly misinformed. Skar are good speakers for what they are but damn. Lol.
Jeffrey Hald my zv5s would destroy zvx's. I have them pulling 4k each off a lithium charge while staying over 14 volts. And those are a model below the nightshades. Have you ever hear either of the subs correctly set up before. The sundown will sound like 2 or 3 of those skars you mentioned. Lol. I'll put a solo zv5 against 2 of those zvx's all day. Hit 28 hz and still be louder.
you have multiply your measurements by integral of signal phase (Sine wave). For 50Hz sine wave its around 0.7 I think
Could you elaborate on this a little more?
No need because it's incorrect. There will always be a phase difference between voltage and current when driving a reactive load. How much that difference is depends on frequency, to be sure, but it is also influenced by the amount of capacitance or inductance in the circuit and that is not a constant from one driver to the next or even from one enclosure to the next.
You have to be able to measure the time difference between current and voltage in order to get the power factor and then, add that as a multiplier to the power formula.
This video is also completely useless as this method will only get you apparent power or, volt amps... not real power. So even if we're to assume the power factor is .7 and the measured VA was 1000, then real power is only 700 watts.
But... the power factor in this case could be 40% or even less.
@@BrandonBuckaudioanarchy so how would you go about measuring the actual wattage coming out of the amplifier? You seem to know a lot about this stuff?
@@TheDeluxe4O it is complicated because it changes alot the smd amm does it in real time and helps see box rise
@@BrandonBuckaudioanarchy can it be done with a 2 channel oscilloscope that will show you the phase angle.
Its an AC signal, it doesn't have a positive and negative, I don't know why you specified which lead goes to which terminal, or which speaker wire to put the clamp meter around...
If you add place an amp clamp to the power feed and a Voltmeter (both set to DC current this time) and repeat this test , by doing the same math you will find the power of this amplifier, and if you divide the reading shown of this video (500W or so) by the reading i'm suggesting you will get the efficiency % , here you can figure out the amount of wasted energy due to heat.
How does this work on a DUAL voice coil sub..??
TELL YOU WHAT GUYS IME JUST GOING TO TEST IT BY MY EARS
do you think you could please help me out here? I needa upgrade my alternator because my system drained my last battery and killed a cell. i bought a new battery and i can't get a new alt for a while so i am just careful about my volume level. i want to know what my max volume level should be at without draining my battery. how should i do this? i was figuring i make sure the battery gets at least 10 amps from the alt and 70 amps to my stereo (80 amp max output alternator).how can i measure it?
As others have said, you're measuring apparent power in volt-amps, not true power in watts. The inductive load of the speaker will not have a power factor of 1.0. 40Hz is a fortunately a good frequency for even cheap multimeters, but true RMS meters with a higher accuracy would tend to give better results.
doesn't matter where u put the clamp meter + or - it's ac voltage
Even then, trying to measure power coming out of an amp only tells you what the amplifier's efficiency is, assuming that the harmonics (%THD) are contributing to the total power output. Harmonics are not desirable in radio (FM,AM,two-way, CB, etc.).
It's 485 watts 50x9.7
I tried to read these comments for an answer, but after seeing how dumb done of these people are that in text I have up. My question is simple yet I'm unsure, do you need to have a subwoofer hooked up you the amp when testing the output or can you do it like a "dry run"? I want to be sure off the power I'm pushing before I got and push it through my speakers to be on the safe side. Don't need to create magic smoke over a goofy test. Thanks
Everyone also be sure to listen to nothing but a 40hz test tone to be sure you always get your full wattage. NEVER listen to music, or test with music even to see how your wattage jumps around, cause ya know, that would be stupid.
How is this valid without a scope? Could be clipping ..
indeed , clipping and sidtortion . not accurate test.
If you amp has built in clip detection
@@adaboy4z this amp does not
You.missed details as in what to set meters too
1ibgreek. Wrong. MOST aspects of car audio run on DC. AC power is speaker power.
Right the power going to the speakers is ac that why he tested it in ac volts
Ah you know, i simply connect a 10W resistor and count down till it blows. Less seconds equal more watts. And you can do it all day in the neigbourhood. Ok it smells a little.
XD
nice 500 watts of CLIPPED power you got there bud
😂
So this guy has 1 channel hooked up at 4ohm..... so it's not bridged? N if it's only hooked to 1 speaker at 4ohm its got to be a 2ohm speaker wired in series... if it was 4ohm speaker it'd be wired at either 2ohm or 8ohm depending on if it was wired parallel or in series...And if it's not bridged if it was bridged that would be pulling twice to wattage at 1000 watts because it's 4ohm ... So if you were to rewire that sub in parallel down to 1 ohm and Bridge the amp would that bring it to 1 ohm giving it the full 1500 Watts or would it bring it to .5 ohm giving it close to 3000 possibly damaging the amp...?
It's a mono amp lol. There is no bridge.
U can't bridge a mono amp
Kevin, you’re the owner of Skar Audio and you think that amps x volts = wattage? That’s not a good look for the company, bro.
I was googling how to measure an amp's power output and got here. With all the arguments below, I don't know which is the right way to do so. Guess I'll have to find $400 for an SMD product.
I got see sick watching, too much swaying bro.
Camera was blurry when showing you adjusting the amp, could not see which one you adjusted w/ screwdriver, needed to focus.
Oh well, what do you spect for free info, right?
lol
It saw 539.845 watts lol I did the math
It's not an RCA lead. RCA is a brand that makes audio and visual products, the cable is called a phono lead.
dude......
please shut the fuck up if you dont know what you are talking about
lol he told you to shut the fuck up and politely added please.
Has anyone ever purchased a Skar audio anything? I already know the answer
💩
"Settings wise as you see right here "
Points camera at Blurry out of focus scribbles 😂😢
I couldn't see shit lol. But I'll Google what the symbols mean and how to use a multimeter. Smh imatard
this is a joke! youR numbers mean nothing. Get an oscilloscope before your next video.
suppose to disconnect the speaker. lol
No you are not you need a resistive load so the amp will put out a output.
newb
I really think he's lying about only one amp is being played. Why not just up plug the power rca's etc from the other amp instead of having people believe his word, but I'm hearing him say we have both amps on than shows the lights but than focuses on the one again. I wouldn't have people thinking that. Do it right or not at all.
This is such bull*hit. V x A=VA not Watts! And BTW How can. You measure power output without knowing distortion? Those numbers are absolutely useless.
+Bad Mopar
voltage (electrical potential) x Amps (current) = Power (watts)
So P=V*I or more simply put, Watts = Voltage x Amps.
Also you would only do this after you set the gains on the amp to see what kind of power the amp puts out without distortion.
Trust me i'm an engineer
well then you would just use power = I^2RMS x R
but for the average person, you can't really explain that. i was trying to explain it simply.
Bad Mopar Have to read up on Ohms law.
This works for DC, not AC. For AC P=I*V*cos(phi); Since he uses some kind of ac signal...
cos(phi) is an angle of your AC sine wave at current step.
An utterly useless and completely misguiding tutorial and the results will not even be in the ballpark of a reliable measurement. A speaker is a highly reactive load. Power testing needs a 1 kHz low distortion sinusodial input. It needs a constant resistive load and you have to measure the output distortion with a THD meter (or at least with an oscilloscope).
Why would you test power output using a 1000 hz tone? That would be completely useless if you were planning on using the amp for a subwoofer. You probably already know this but almost all amplifiers put out more output at higher frequencies.....
+Andrew Corbett because one want to measure after a standard method in order to get compareable results and not a meaningless random value.
The max power output using a dummy load at 1000hz is also useless when determining actual output when driving a subwoofer. You have to test the output at all levels all the way down to subsonic in order to get anywhere near real world output and even then its still an estimate because music is dynamic.
Andrew Corbett Sorry, this is complete BS. You only refer to different measurement frequencies (aka "sweep") if you want to measure the frequency response, phase, THD or burst power (which also doesn't represent a real world value).
Maybe you should have a look at this paper: cdn.rohde-schwarz.com/pws/dl_downloads/dl_application/00aps_undefined/RCS0702-0032.pdf
Do you even use amplifiers in the "real world"? You seem like some kind of nerd CEA compliant drone that can't grasp any other concept besides what a lab setting provides for testing amplifiers. I will try to place nice with you though. We can both agree that the CEA standard uses a voltage higher then what you would see in a car. So that alone makes it almost useless information. The point I'm trying to make is if you want to have any clue at what your amp is actually outputting you must test it when its in your car with the car running. If these test were performed using the cars power supply they would then having some meaning. You cannot play a fucking 1000 hertz signal through an amplifier, measure its THD and wattage and then claim that it will hold that wattage all the way down to subsonic frequencies because I'm telling you flat out it isn't going to do that kind of power at 30hz. THIS IS WHY THE RATINGS ARE MEANINGLESS. The only good rating is one that shows continuous power output and THD all the way down to 20 hz.