posted
As some of you know I've questioned this a couple of times throughout the season. Well there is a flaw to the system that NSPL uses to measure power during competition. To find TRUE RMS power a peak hold function is not to be used during testing to find the amperage or voltage. This is how NSPL is determining power by using the peak hold function on both meters. No matter if they are true rms meters or not they still will not show true rms power by using the peak hold.
I've confirmed this with several big name competitors in Db Drag along with some manufactureres in the industry and they ALL have told me that NSPL's method is wrong for measuring true rms power.
Now it is a fair way if all competitors are being tested this way, but I think that the power limitations in some of the classes should be bumped up since the power that is being calculated is not rms but a combination of rms and peak power.
For example my Sundown saz1500d's were told to me that they are making 1747 watts of power rms at 1.7 ohms. There is no way this is possible out of this amp and I have confirmed this with the owner of Sundown Audio that his product can not do this type of power under the specified load. I have measured the amps for TRUE RMS power using the hold function on a meter 3 Seconds into a burp and got completely different readings than what we are getting at the events.
Like I said it's fair if everyone is being tested for power this way, but I do think that the power classes need to be restructured since it's not rms power that we're using and NSPL is advertising rms power as the breakdown for the classes. We all know peak power ratings mean nothing at all and rms is what counts. Well a combinaton of rms and peak is still pretty much worthless to us as well. Why not just go by manufacturer rated power instead of trying to get inaccurate numbers like what's being done at all the events this year?
If nothing is going to change then at least say that the classes aren't determined by rms power. Tell the competitors that it's a combination of peak and rms to determine the competitors power class.
-------------------- TEAM SUNDOWN AUDIO 2009 NSPL Car 1801-3600 Watt Record Holder: 151.2db 2009 NSPL Car 3601-Up Watt Record Holder: 152.6db 2009 NSPL Car Hardcore Record Holder: 155.2db 2009 NSPL Car 3601-UP, Car Hardcore, and Car Points World Champion Posts: 1855 | From: The Triad | Registered: Jan 2008
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quote:Originally posted by Nightshade: As some of you know I've questioned this a couple of times throughout the season. Well there is a flaw to the system that NSPL uses to measure power during competition. To find TRUE RMS power a peak hold function is not to be used during testing to find the amperage or voltage. This is how NSPL is determining power by using the peak hold function on both meters. No matter if they are true rms meters or not they still will not show true rms power by using the peak hold.
I've confirmed this with several big name competitors in Db Drag along with some manufactureres in the industry and they ALL have told me that NSPL's method is wrong for measuring true rms power.
Now it is a fair way if all competitors are being tested this way, but I think that the power limitations in some of the classes should be bumped up since the power that is being calculated is not rms but a combination of rms and peak power.
For example my Sundown saz1500d's were told to me that they are making 1747 watts of power rms at 1.7 ohms. There is no way this is possible out of this amp and I have confirmed this with the owner of Sundown Audio that his product can not do this type of power under the specified load. I have measured the amps for TRUE RMS power using the hold function on a meter 3 Seconds into a burp and got completely different readings than what we are getting at the events.
Like I said it's fair if everyone is being tested for power this way, but I do think that the power classes need to be restructured since it's not rms power that we're using and NSPL is advertising rms power as the breakdown for the classes. We all know peak power ratings mean nothing at all and rms is what counts. Well a combinaton of rms and peak is still pretty much worthless to us as well. Why not just go by manufacturer rated power instead of trying to get inaccurate numbers like what's being done at all the events this year?
If nothing is going to change then at least say that the classes aren't determined by rms power. Tell the competitors that it's a combination of peak and rms to determine the competitors power class.
Zach, how about you contact Fred Jr. directly with this issue instead of on this forum. Some issues need to be addressed directly so that corrections, if any, will be made in a timely manner.
Posts: 176 | From: Greensboro, NC | Registered: Oct 2007
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posted
The best way is using MAX hold (NOT PEAK NOR BURST HOLD) and BOTH clamp and voltmeter need to be true-RMS.
When your amps clip, a NON-true RMS meter will show a LOWER reading, due to its inherent filtering and rectification of the AC, that will make the DC part of the wave (clipped signal) transfer less energy than a non clipped sine wave.
posted
I do think that the way it is being determined right now is the fairest way possible and I stated that in my paragraph above. The only issue that I have is that I'm making way less power in my case but each time I'm at a show I'm told I'm only within a few watts of my power class's limit.
Lendel, I've tried to contact Jr. several times about this matter but every time I call the shop he's busy. How am I supposed to talk to someone about this issue when I can't even get him on the phone? I'm not trying to hide anything at all, I just want to see what others think about the situation so that if we agree on it I can try my best to get it fixed.
In no way am I saying that there's anything wrong with what's going on, it is very fair but not acutally rms power. If this is true then we should either find true rms power or call the power classes something other than rms power classes or even raise the power limits in each class.
I wouldn't call Jr. out and that's not what this is about. I love Fred and would never try to decieve him in any way at all. If anything I'm trying to help the organization by getting something fixed that may be a potential flaw in some people's eyes. That's the thing I love about Jr. he actually listens to his competitors unlike some of the other organization owners (Wayne Harris). I mean this in no way harmful to Fred and I'm sure if he reads this he'll know that. I just put it here since I haven't been able to talk to him about it and wanted some feedback from other's that are effected by it.
-------------------- TEAM SUNDOWN AUDIO 2009 NSPL Car 1801-3600 Watt Record Holder: 151.2db 2009 NSPL Car 3601-Up Watt Record Holder: 152.6db 2009 NSPL Car Hardcore Record Holder: 155.2db 2009 NSPL Car 3601-UP, Car Hardcore, and Car Points World Champion Posts: 1855 | From: The Triad | Registered: Jan 2008
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quote:Originally posted by Nightshade: The only issue that I have is that I'm making way less power in my case but each time I'm at a show I'm told I'm only within a few watts of my power class's limit.
And EVERYONE else is in the same boat. If you build for DBdrag, you don't test in the kick....in other words, who cares? Test the same way the org you are CHOOSING to compete in tests. Believe me, there are WAY worse ways to be classified.
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