is this possible: clipping detection using a dmm?

[hoss 5,000+ posts]

hehe, i dont know that i was using the corret terminology, its just what i call it //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[IgnoreMe 5,000+ posts]

Clipping IS NOT DC, it's still oscillating, so it's AC. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

i know now, check the edit of post 7 //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[DBfan187 5,000+ posts]

DOH! I've been squeaked!

 

[Safe-N-Sound215 10+ year member]

I don't think I've ever heard the term "power compression" used in reference to an amplifier before.
But the essence of what Hoss is saying is right.....eventually you'll reach the rail voltage of your amplifier and the voltage will cease to increase any further.

I certainly would not use this as a method by which to set gains or determine the level of acceptable distortion, however.

Me either. But I'm aslo not half as knowledgable as some of you guys on here.//content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

But this is what I found on jbl's site as far as power compression goes. Not much, but gives you an explanation as to what it is.

http://www.jblpro.com/pages/general_faq.htm#What

 

[squeak9798 5,000+ posts]

Clipping IS NOT DC, it's still oscillating, so it's AC. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Already been covered.

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[squeak9798 5,000+ posts]

well currently i just use the standard dmm, test tone procedure as i dont have access to an oscilloscope anymore.
i was just trying see if there was maybe a different, and better, way of going about it.

Either by ear, or with an O-scope.

Those are pretty much the only options currently.

You could also try using different level test tones (0db, -3db, -6db, etc) & the DMM method.

thch on here a year or so ago was thinking about making a little project that would have an LED light bar denoted with levels of "distortion" (1%, 10%, etc) IIRC......don't know what ever came of it though.

 

[IgnoreMe 5,000+ posts]

Either by ear, or with an O-scope.
Those are pretty much the only options currently.

You could also try using different level test tones (0db, -3db, -6db, etc) & the DMM method.

thch on here a year or so ago was thinking about making a little project that would have an LED light bar denoted with levels of "distortion" (1%, 10%, etc) IIRC......don't know what ever came of it though.

yup, i remember that thread.

yea, im satisfied with my output (i use -6db for subs and -3db for speakers), so thats not an issue. just a little thing that popped into my head.

 

[jblpower 10+ year member]

I would not use the method of power compression to determin clipping. In most amplifiers I have benched on my scope clipping starts well before the voltage stops increasing. For example on my xxx-6500 clipping starts @77.2vac, but the amp is able to reach 99vac before the voltage starts to taper off.

 

[Grmanalishi 10+ year member]

You can calculate the amp output voltage you're looking for with your system/amp then use the digital multi-meter to find that voltage. If you exceed that output voltage you will clip the amp.

The output voltage = (RMSxOhms)**0.5 or square root (RMSxOhms):

http://www.subwoofertools.com/forum/setgain.asp

 

[squeak9798 5,000+ posts]

If you exceed that output voltage you will clip the amp.
The output voltage = (RMSxOhms)**0.5 or square root (RMSxOhms):

http://www.subwoofertools.com/forum/setgain.asp

That method assumes that the amplifier is capable of exactly it's rated power.

With overrated or underrated amplifiers, it doesn't work quite so well..........