Mr. RF62 Posted May 1, 2009 Share Posted May 1, 2009 Are subwoofers limited to the current coming out of the wall outlet? And does it depend on the capacitors in the unit on the amp board??? Ex: 120v x 15amp = 1800watts. So if there is a 2000watt amp, then is it limited??? Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted May 1, 2009 Share Posted May 1, 2009 I'll let the electrical guru's chime in but I would think that capacitors in the amp might give you some bursts higher than what the outlet actually puts out. Also, the breaker is not going to pop at 15.1 amps and may let more amperage through for short periods of time. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted May 1, 2009 Share Posted May 1, 2009 since the amplifier architecture is a factor here (class A,class AB, etc) the best way to investigate is to determine from the UL label what the current rating is. for example, one amp I have draws 430 watts from the wall or 3.5 amps. it only produces 240 watt to the speakers. If I assume 3X the power for turn on surges, the max power draw would be about 1300 watts or a little over 10 amps. Quote Link to comment Share on other sites More sharing options...
TheEAR Posted May 1, 2009 Share Posted May 1, 2009 Capacitors are a reserve bank,the greater the capacitance the more reserve you have. It is very realistic to produce bursts in the 3-4KW range from a 15AMP line. Sustained high level signals are used for torture testing and most amps will even fail trying to meet spec. You will only see/hear limitations of sustained sine waves reproduced at high output. Who listens to sine waves or tests tones non stop? Also we are not driving a bank of resistors to the breaking point here. A 15AMP line will feed even power hungry and inefficient JL Audio Fathom f113. Two such subs on one 15AMP line...I would use caution.Two RT-12d's on one 15AMP line...ha no problem conect even three. When using several power amps subs from one line,make sure to power them in sequence. As turning all the units ON will demand an inrush of current far greater than the single 15AMP line can provide. I managed to run just for kicks four QSC PLX2502 to 3602 amps,two PL380's and two iTech 6000 on one 15AMP line. In standby the demand was ~9AMPS! I switched one after the other in three second intervals,as the iTech and PL380's suck current into the caps like ShopVacs suck saw dust. Quote Link to comment Share on other sites More sharing options...
Mr. RF62 Posted May 1, 2009 Author Share Posted May 1, 2009 Thanks guys for the output/input. The amp in question is a class D type. Quote Link to comment Share on other sites More sharing options...
TheEAR Posted May 1, 2009 Share Posted May 1, 2009 Class D is efficient(dpower raw to output wise), the loss is quite low(compared to class A/B or class A). Unlike class A amplification that has a good portion of the power draw lost in HEAT. Class A/B works in class A at low output levels and switches to class B at higher output levels. Quote Link to comment Share on other sites More sharing options...
Jay481985 Posted May 28, 2009 Share Posted May 28, 2009 Class D are around 80-90 percent efficent.Those amp ratings are usually burst. Besides no one really plays sine waves to really torture a speaker and amp. Also remember a sine wave is half on half off so that helps keep the capacitors charged. Quote Link to comment Share on other sites More sharing options...
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