posted
k...first, remember one of the major laws of physics "energy can neither be created nor destroyed". so with that in mind...
as current flows through a conductor (metal usually) it meets resistance to the current flow. Some materials have a higher resistivity than others. Resistors are made of different materials in different thicknesses and lengths to obtain different resistance values.
so, as the current flows through an amplifier it meets a finite amount of resistance (aka, why amplifiers are not 100% efficient, some energy is converted to heat...and also the hotter an amp gets the less efficient it becomes. NOTE: a hot heatsink isn't always a bad thing, it just means that the heatsink is drawing heat away from the circuit board like it's supposed to). So due to the resistance...the amplifier gets hot. Much of the heat is created in the power transistors which are attached to rails that are in turn connected to the heat sink...
i guess that'll work...make sense?
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--------------------------------- Loud...it's when you can see the ground move, it's when you have to force yourself to breath, it's when the rest of the world ceases to exist. Posts: 4136 | From: Lafayette, LA | Registered: Sep 1999
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posted
i agree with alaska he is right but to answer your second question i have found in most amp designs they draw the same amount of current now i have done some testing of my own and found that if u pre cool the heats sinks u can get away with some pretty stuipd own loads opps just told u one of my sercets!
-------------------- 1-dell smart soulutions 1000D(who needs a head unit ) 1-18" flat screen 4 2500d's 2-solox and 20 cu's TEAM FRANKS DESIGNS spl: 4-solox in a wall tuned 2 28 hz 16-2250ds hopeing two have by 2004 alaska u ready??? lol Posts: 193 | From: lAFAYETTE | Registered: Dec 2001
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it becomes less efficient due to the heat and therefor needs more current to produce the same power.
-------------------- "Those who give up liberty for the sake of security deserve neither liberty nor security" - Benjamin Franklin
DiRtY SoUtH DEAF SqUaD
Elemental Designs
To cheat is to admit defeat
--------------------------------- Loud...it's when you can see the ground move, it's when you have to force yourself to breath, it's when the rest of the world ceases to exist. Posts: 4136 | From: Lafayette, LA | Registered: Sep 1999
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posted
i thought that reply went thru a loong time ago...wtf?!!?
elijah...my phone is DOA right now so if it's busy that's why
the extra current draw won't be too drastic, but there will be more current pulled when hot
-------------------- "Those who give up liberty for the sake of security deserve neither liberty nor security" - Benjamin Franklin
DiRtY SoUtH DEAF SqUaD
Elemental Designs
To cheat is to admit defeat
--------------------------------- Loud...it's when you can see the ground move, it's when you have to force yourself to breath, it's when the rest of the world ceases to exist. Posts: 4136 | From: Lafayette, LA | Registered: Sep 1999
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posted
About the pre-cooling stuff: Do not do that with the stuff like "coldspray", you know the things that generate extreme low temperatures by expanding gas. Not all transisitors can stand that extreme cold. So be carefull not to spray that stuff too long at 1 spot on hte heatsink. It could as well kill one of the transistors. Most automotive electronics work well within a temp range of -40°C up to 125°C. (most are speced up to 80°C but for safety reasons the devices are tested at 125°C) I don't think car-audio components meet these extreme specifications, thats why it's not too smart to cool them down too heavy. Some extra info: decrease in temperature is in most cases an increase in conductivity.
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