bigjsurdaddy Posted December 31, 2009 Author Report Share Posted December 31, 2009 when i did my calculations i did it for 70% and gave my self room for like 10% less effeincy. so i think i will still be good. Quote Link to comment Share on other sites More sharing options...
IH8PunkRok Posted December 31, 2009 Report Share Posted December 31, 2009 i dont get how that works... *note* im not saying anyone is wrong but why does it become less efficient with less resistance? makes no sense to me Quote -Matt2005 Dodge Magnum RTJVC KD-AVX1 2 PPI S580.2 Obsidian Audio ST1 Horn Tweeters PRV 8MB450s Audio Legion 3500.1D 2 RE MT 18s 360 ah LiFePO4 BatterySHCA 2/0 155.2 @ 29 hzKicker CVR 15's buildDD 3512e buildMini T-Line Build(6) 8s BuildNightshade 15s Wall BuildMagnum AB XFL 12s BuildNewest Magnum Build Link to comment Share on other sites More sharing options...
bigjsurdaddy Posted December 31, 2009 Author Report Share Posted December 31, 2009 they did another clamp test on smd a while back. those were the first 1500d's. i think they got a little better over the last 3 years. he's the link. http://www.stevemeadedesigns.com/board/ind...showtopic=50753 Quote Link to comment Share on other sites More sharing options...
skittlesRgood Posted December 31, 2009 Report Share Posted December 31, 2009 they did another clamp test on smd a while back. those were the first 1500d's. i think they got a little better over the last 3 years. he's the link.http://www.stevemeadedesigns.com/board/ind...showtopic=50753 ya i know, but they dont say efficiency on that test. i just wanted to show you efficiency numbers. Quote If I answered you in a well mannered, informative way, you asked a good question or had a good attitude. If I was an asshole, you asked a stupid question or you had a fucktard attitude... or I was in a bad mood. Team BassickHU: Pioneer AVIC Z110Front: Peerless SLS 6.5", Peerless HDS 4", Rainbow tweeter - running activeAmp: JL HD600/4 and DC 4 channel (bridged to midbass)Processor: JBL MS-8Subs: 2x 12" AA MayhemsAmp: DC 3kElectrical: DC power 270xp alt. 1/0 big 4. XSpower D3400 and six D680s. http://www.stevemeadedesigns.com/board/topic/121795-29-update-the-buick-is-getting-a-rebuild/ Top career scores: DBdrag 151.7 MECA SQ 82.25My SOTM build Yeah. im pretty sure they dont warranty retarded people. Link to comment Share on other sites More sharing options...
bigjsurdaddy Posted December 31, 2009 Author Report Share Posted December 31, 2009 ya i know, but they dont say efficiency on that test. i just wanted to show you efficiency numbers. and that does help. but i think i left enough head room for what i'm doing for the effiency to drop to about 59 or 60%. Quote Link to comment Share on other sites More sharing options...
kirill007 Posted December 31, 2009 Report Share Posted December 31, 2009 The amp efficiency depends on the amp used, but usually( in general) the amps efficiency drops if the impedance drops. Quote Thinking is the root of all problems... You ALWAYS get what you pay for. Link to comment Share on other sites More sharing options...
finkster Posted December 31, 2009 Report Share Posted December 31, 2009 HEAT people HEAT.... Quote DAT 4125------>RE XXX comps active Eclipse cd7000 I serve drunks for a living Link to comment Share on other sites More sharing options...
Decaf Posted December 31, 2009 Report Share Posted December 31, 2009 (edited) i dont get how that works... *note* im not saying anyone is wrongbut why does it become less efficient with less resistance? makes no sense to me transfering heat in mosfets diodes transformers all have resistance/an affect on efficiency Edited December 31, 2009 by Decaf Quote Link to comment Share on other sites More sharing options...
cqtama Posted December 31, 2009 Report Share Posted December 31, 2009 yes im sorry didnt mean to mislead, was just trying to explain some basics.the amp puts at more power at lower ohm loads but will have more of a draw. so you need to up the electical system (batteries ans alternators) a little bit more Quote R.I.P '01 blazer you treated my ears well until your transmission blew up. New Project [top secret] 149.0 db on music driver window open; so close I feel some boners are fueled by viagra and not true intimacy!......if you know what i mean.... I swear... sometimes I wish I was retarded so I could just agree with everyone x. Link to comment Share on other sites More sharing options...
Boon Posted January 2, 2010 Report Share Posted January 2, 2010 Amps are less efficient at lower ohm loads. They make more power but they take even more power to do so. For example, completely made up but hey... At 4 ohms, an amp might make 1000w and require 100A of input current to do it. At 2 ohms it might make 1800w and require 200A to make it Then at 1 ohm you might see 2400w but you will see close to 300A being pulled. This, as mentioned above, is mostly due to inefficiency in the MOSFETs/Transistors and transformers used in the amp. If you look at the specification RDS(on) for a MOSFET - this is the Resistance Drain - Source for a FET. It presents an in-line resistive load to the electricity in the amp. Say we have 20A drain - source and the FET has an RDS of 5 milli-ohms. The FET will drop 0.1v across it. If we increase the current across the part to 60A we are losing 0.3v instead. This effect is most pronounced in the power supply section where the parts are carrying heavy current at the supply voltage (12.x or whatever) so a loss of 0.3v equates to a loss of approximately 2% power. This doesn't seem like much but it doesn't allow for the increase in temperature either. As the junction temperature rises the RDS increase as well, sometimes by a factor of 2 or even more. So suddenly you're losing 5% of your power just in heat going through the power supply section, and you see how it starts to add up. Quote 10.x volts fo' life! Link to comment Share on other sites More sharing options...
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