i don’t understand, too little power
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=102398
Printed Date: April 29, 2024 at 12:21 PM
Topic: i don’t understand, too little power
Posted By: theetimurban
Subject: i don’t understand, too little power
Date Posted: February 21, 2008 at 9:02 AM
I just read Chuck McGregor's post on bcae1.com about too little power, and he states that a clean signal (vs. a fully clipped signal) will create more displacement. More displacement means the woofer moves more air, and the more air that is moved, the higher the SPL (right?). So, if this is true, why would people that compete in SPL competitions run a clipped signal? Also, just a quick thing here, my home town is a pretty big party town, so my friends and I are heading there for spring break, which isn't really relevant, but what is, is that I'll be able to go to my dad's shop and use his oscilliscope (to finally get my gain set 100% correct). I have a pretty amazing ear, in that I can tune pretty much any instrument without a tuner, so when I was setting my gain, I did the whole, turn the volume up to 3/4 and play a tone (I used 40hz, is that okay?) and turn the gain up until you hear distortion. Anyway, I know that I'm looking for the "perfect" sine wave when I set the gain, but is there anything else that I need to be looking/listening for?
Replies:
Posted By: collyn eastham
Date Posted: February 21, 2008 at 9:13 AM
O-scopes and sinewaves are good and all, but, you play music...not sinewaves, and you listen with ears...not test equipment. I have built and tuned some of the best sounding cars in the world and have never used a scope or a sinewave. I set gains where it sounds best and is balanced with the other amps/channels.
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Collyn Eastham
a.k.a. 300MBQuart
08 HHR Panel
Posted By: collyn eastham
Date Posted: February 21, 2008 at 9:16 AM
OH...and a clean signal WILL outperform a FULLY clipped signal. SPL competitors do not run the amps at FULL CLIP. The run them into clipping, but not full clipping.
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Collyn Eastham
a.k.a. 300MBQuart
08 HHR Panel
Posted By: theetimurban
Date Posted: February 21, 2008 at 9:44 AM
well, haem said in this post: https://www.the12volt.com/installbay/forum_posts.asp~TID~83365~PN~1 that you should do it by ear first and then use instrumentation, if possible. In a few weeks I'll have the opportunity to use an o-scope, so I'd like to take advantage of it. -------------
Posted By: jeffchilcott
Date Posted: February 21, 2008 at 12:31 PM
We run amps slightly over into a clipped signal because of the power. There is a fine line between where you will have a good gain in power, to where you will damage seakers.
There are times where I have pushed subs to 3-4 times thier rated Peak handling, even some that have been pushed to 2-3 times thier peak handling for a solid 30 second run.
So amps make up to 30-40% more power at 15-20%THD then at 1% THD.
This is something that I only use for a comp setup only, street use I try to stay below 1% THD.
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2009 0-1000 Trunk WR 154.0DB 2009 1001+ Trunk WR
2007 USACI World Champion
2007 World Record
2006 USACI Finals 2nd Place
Posted By: theetimurban
Date Posted: February 21, 2008 at 4:34 PM
Well that makes sense. Thanks much. But yeah, I was wondering about that, and it's not like there's anyone around here that I'd be able to ask, since there's only 2 shops here and one of them is owned by an 80-year-old Italian guy who's just tryin to turn profit, and the other one, well, let's just say his merchandise is hotter than San Jose in July.
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