Car audio Rumours
10-01-2009, 02:11 PM
#101
so if i have a 4V preout going into my 200w RMS amp, I am going to put out more than 200w by upping the gain to a sensitivity of 2V?
i'm not upping the power of the amp, simply choosing when i want it to achieve its maximum.
when increasing the gain on an amp you are just increasing the ratio of amplification. when you are turning up you headunit, you are increasing the actual initial power of the signal output. all headunits preouts are attenuated and only achieve their rated preout levels near maximum volume.
keep turning up a deck, and it will put out more and more power...it may not be clean, but it will continually increase.
turn up an amp, and it will not continually make more power as its turned up, it will max out and only produce its rated power around the equivalent sensitivity of the voltage being put in.
so by turning up the volume on a headunit, you are essentially uping the power of the deck.
and by turning up the gain on the amp, you are not uping the power on the amplifier, simply choosing when to make maximum power.
you can't choose on a headunit to make maximum power or a specific preout voltage at 50% of the volume ****.
volume=power
gain=sensitivity
....just because they both can make a system louder, doesn't make them both volume *****. lol, otherwise why wouldn't manufacturers just label them volume on the amp?
Last edited by jstoner22; 10-01-2009 at 02:14 PM.
10-01-2009, 02:42 PM
#102
Administrator
Join Date: Feb 2006
Posts: 16,855
i thought the whole idea of the cap is because it CAN put out its power in 34milliseconds. a batt and alternator can't deliver it that quickly, even if they can put it out.
isn't it just a bandaid for a system that can keep up, but is just a little slow of its feet? if a system can't keep up it can't keep up. the cap just buffers a decent system for that .5 second or whatever it is to allow the batt/alt to actually deliver the power. after that it would be useless, but it isn't meant for sustained voltage, just that quick charge/discharge in between
isn't it just a bandaid for a system that can keep up, but is just a little slow of its feet? if a system can't keep up it can't keep up. the cap just buffers a decent system for that .5 second or whatever it is to allow the batt/alt to actually deliver the power. after that it would be useless, but it isn't meant for sustained voltage, just that quick charge/discharge in between
10-01-2009, 02:47 PM
#103
Administrator
Join Date: Feb 2006
Posts: 16,855
Kev - the Jacobs Accuvolt is exactly the product you describe. Essentially a tightly regulated power supply for your car.
Sleboda - it is the maintenance of current that sustains the voltage. When the current is exhausted, the voltage drops. Oh and it sounds like the voltage regulator is shot on your buddy's Grand Prix.
Who doesn't have 0ga speaker cable? I mean really..
Which is better sustained Voltage or a High capacity of current, or potential current.
Who doesn't have 0ga speaker cable? I mean really..
10-01-2009, 03:37 PM
#104
50 Watt CAFz'r
Join Date: Apr 2004
Posts: 117
10-01-2009, 04:28 PM
#106
That is an excellent explanation behind why a cap helps. The cap is there to support the load until the alternator can take over. IF the current draw exceeds what the alternator can ultimately provide, then eventually you will exhaust the cap and system voltage will fall. This is the crucial part people don't get: If your system draws current in excess of what your alternator can provide, you WILL run out of power. Adding capacitance only prolongs the inevitable.
In my books though, where that's only the fraction of any specific note being played, that's essentially useless.
10-01-2009, 05:21 PM
#107
oh man ive heard so much about this cap/no cap debate, from what ive been told seeing as how im not an expert in car audio, for the cost of adding a DESCENT quality cap. its probably better to just get a small power cell or second battery, it just supplies more power so even if the car is off i can listen to my music and enjoy it without killing my primary battery....iuno thats just what ive been told
10-01-2009, 06:24 PM
#109
Caps really do jack a second battery is good though. Dual alts meh unless u runnin lots power it not neccessary! By lots I mean 10k daily driver. A decent battery keeps a 3k runnin good daily! I run a 2nd bat it helps! I had a 12faraf Tsunami digital hybrid and it didn't do a damn thing for my voltage but use it for makin the digital read outwork! If u car off it really aint gonna do squat! Put a 2nd batt in!
10-01-2009, 06:24 PM
#110
I would think just swaping out a better\newer battery would help if not eliminate diming lights for roughly the same cost as a cap.
jstoner22: There is some misinterpretation on both sides I believe. Let me put it this way.
You have a deck playing a 100hz tone ..you raise the volume so that your 4volt deck outputs 2 volts to a 200watt amps.. you set the gain at 1\4 and the amp is connected to a 4ohm resistor..you can calculate from that how much power it outputs, lets say 100 watts continuous. So if you raise the level on the deck (that ups the voltage) or you raise the gain.. both will show an increase in output power from the amp.You raise either or enough and you will hit your 200watts or more if you push either or into clipping.
They are the same. I don't see how one can say the gain isn't a volume seeing as how the definition of volume is so broad:Volume is the term used for loudness in consumer electronics. I don't think you can dispute that raising the gain affects volume.
You can say the word sensitivity all you want
jstoner22: There is some misinterpretation on both sides I believe. Let me put it this way.
You have a deck playing a 100hz tone ..you raise the volume so that your 4volt deck outputs 2 volts to a 200watt amps.. you set the gain at 1\4 and the amp is connected to a 4ohm resistor..you can calculate from that how much power it outputs, lets say 100 watts continuous. So if you raise the level on the deck (that ups the voltage) or you raise the gain.. both will show an increase in output power from the amp.You raise either or enough and you will hit your 200watts or more if you push either or into clipping.
They are the same. I don't see how one can say the gain isn't a volume seeing as how the definition of volume is so broad:Volume is the term used for loudness in consumer electronics. I don't think you can dispute that raising the gain affects volume.
You can say the word sensitivity all you want
