DC5K Clamp Test - Second Try with oscope hooked up

[moh.vze.com]

Alright. I've recorded 5 different clamp tests. The second video uses the Pmax function on the clamp meter and the rest doesn't use that function for more accurate results.

40Hz test tone @ 0dB was used.

Here is a video showing you guys the setup.

What I've done differently this time was plugged my leads into the amplifier speaker terminals.

The final ohm resistance actually read 1.1ohms (not 0.7 ohms like I had thought).

http://youtu.be/9zBBChAqD3Y

DC5k Clamp Test - Run 1:

http://youtu.be/1pkedpaSrJU

Clamp Meter Max AC Current: 61.4A

Oscope Max AC Voltage: 66.8V

DMM Max AC Voltage: 63.6V

Results:

Equation: AC Current * Ac Voltage:

Using Oscope Voltage:

61.4A*66.8V = ~4101Watts

Using DMM Voltage:

61.4A*63.6V = ~3905Watts

DC5k Clamp Test - Run 2 - Used Pmax Function:

http://youtu.be/dKB2PyIQEow

Note: Using Pmax function on Clamp Meter

Clamp Meter Max AC Current: 76.6A

Oscope Max AC Voltage: 69.3V

DMM Max AC Voltage: 65.8V

Results:

Power = Current * Voltage

Power = 76.6A* 69.3V = 5308 Watts (Using the oscope voltage reading)

Power = 76.6A * 65.8V = 5040 Watts (Using DMM Voltage Reading)

DC5K Amplifier Clamp Test - Run3

http://youtu.be/cCEVvoxOSoU

Note: I rolled the volume up and down a bit. Might have skewed the results.

Clamp Meter Max AC Current: 60.6A

Oscope Max AC Voltage: 66.8V

DMM Max AC Voltage: 63.3V

Results:

POwer = 60.6A * 66.8V = 4048 Watts (Using oscope volt reading)

Power = 60.6A * 63.3V = 3836 Watts (Using DMM volt reading)

DC5K Amplifier Clamp Test - Run4

http://youtu.be/AkLs6PmTjCo

Clamp Meter Max AC Current: 53.6A

Oscope Max AC Voltage: 69.3V

DMM Max AC Voltage: N/A

Results:

Power = 53.6A * 69.3V = 3714 Watts

DC5K Amplifier Clamp Test - Run5

Video: See Post #3

Note: This was my final Clamp Run

Clamp Meter Max AC Current: 59.3A

Oscope Max AC Voltage: 68.1V

DMM Max AC Voltage: 64.2V

Results:

Power = 59.3A * 68.1V = 3741 Watts

Power = 59.3A * 64.2V = 3809 Watts

Any thoughts? I was hoping it would be more power than this. Would it make a difference if I go back and reset my gains to the point of clipping and go down a little? I left a pretty big gap when I was setting my gains.

Edited December 29, 2012 by moh.vze.com

[CJ18]

What frequency was used for each test?

[moh.vze.com]

I couldn't post all of the media links in the first post so here's Clamp run 5

http://youtu.be/liMOocFPjF8

Here is a video of the resistance reading for the subs nominal load:

http://youtu.be/R_N1AOg5JC8

40 Hz @0dB test tone was used on all of the tests.

I would like to note that my box is tuned to 30hz and I have the SSF set to 25Hz.

Was I suppose to burp at different frequencies? (Ie: Burp at 30hz, 35hz, 40hz, 45hz, and 50hz)

Edited December 29, 2012 by moh.vze.com

[crunkjuice1]

[CJ18]

If you want to see a true output reading, you need to check at 30hz, 35hz, 40hz, 45hz, and 50hz. Music is dynamic, you are not going to see a constant 40hz during a song. This is why clamping a daily setup just really inst practical.

Here are the numbers from a test I did on one of my 7.5ks last year.

HZ----AMPS----VOLTS----WATTS----OHMS----Voltage Drop

30----.9----96.5----7806.85---1.19----15.2v

35----78.2----100.2---7835.64---1.28----15.2v

40----72.2----103.6---7479.92---1.43----14.1v

45----62.2----107.8---6705.16---1.73----14.7v

50----61.5----106.9---6574.35---1.74----14.7v

As you can see my reactive impedance changes with the frequency. With the impedance change comes more or less power.

[CJ18]

Also if you want accurate numbers, you dont want the max readings, you want readings taken at exactly the same time. Your max acV could be 68v and your max acA could be 60a, but at the time your acV was 68v, your acA may have been different.

[Kyblack76]

Are you using your scope just to read voltage? Or are you using it for that AND to see clipping as well? Thought thats why you had a scope?

Only power that matter is clean power..... no?

Or am i lost?

EDIT at 15 sec of second vid i see flat wave.... Maybe i dont understand. So forgive me.....

Edited December 29, 2012 by KyLar96

[moh.vze.com]

Are you using your scope just to read voltage? Or are you using it for that AND to see clipping as well? Thought thats why you had a scope?

Only power that matter is clean power..... no?

Or am i lost?

Well I originally used the oscope for setting the gain without the speaker wires hooked in and it had a clean curve. But when I hook up the speaker wires to the amp and play the tone at that exact same volume, I'm getting dirty power.

That's where I'm a bit confused. People say to set the gains without the subs hooked up. Maybe someone can chime in on this.

By the way, I don't bump my music with the voltage going below 12.5V.

Edited December 29, 2012 by moh.vze.com

[Kyblack76]

Also, for those that do this, and care about it, (i never have, and dont, but) seeing and figuring your rise, and voltage drop would be ideal..........

And yes,.... you need to do several FREQ's.....from my understanding.

Edited December 29, 2012 by KyLar96

[moh.vze.com]

How do I know which AC Voltage reading is correct? There seems to be a ~3Volt difference between the Oscope and the DMM reading.

I'll probably do another run on all of those different frequencies again tomorrow once someone confirms if it's ok to be somewhat clipping when doing this just for the sake of results -.-

I will also use the DMM for DC Current readings. When I ran these tests, I think the lowest voltage I saw was 11.5V. Average was more around 12V though.

Edited December 29, 2012 by moh.vze.com