What the hell is a line driver?!?!?!

[ravendarat 10+ year member]

but with the line driver he doesnt have to turn his gains up near as much.

Doesnt matter where his gain is at, if the amp gains are set correctly than he still has the same output, just with more head room so his ampreage draw should be very similar

 

[thch 10+ year member]

but with the line driver he doesnt have to turn his gains up near as much.

yes, but that doesn't affect anything related to power.

power losses in the amp are dominated by the output stage and the speaker.

if the amp has +-40V rails, and is putting out 10V into a 4ohm load, there is 2.5A of current.

this is 10*2.5 = 25W from the speaker.

that means (40-10)*2.5 = 75W is dissipated in the amp's output stage.

the voltage gain really isn't an issue, as the typical voltage gain of an amplifier, in excess of 10,000 V/V, is typically too high and feedback is used to bring this down to something usable.

in the end the "amp works less" is a marketing gimmick. I think its best to avoid shopping anywhere that tells you something this dishonest.

for noise purposes, its may be better to have the gains set at a lower setting.

 

[toaster 10+ year member]

of course its better to have your gains set lower. adding a line driver is all about lowering your noise floor. s/n ratio= signal to noise ratio.

my linear pa2 does 36 volts, unclipped.

 

[GrnEydDvl 10+ year member]

yes, but that doesn't affect anything related to power.
power losses in the amp are dominated by the output stage and the speaker.

if the amp has +-40V rails, and is putting out 10V into a 4ohm load, there is 2.5A of current.

this is 10*2.5 = 25W from the speaker.

that means (40-10)*2.5 = 75W is dissipated in the amp's output stage.

the voltage gain really isn't an issue, as the typical voltage gain of an amplifier, in excess of 10,000 V/V, is typically too high and feedback is used to bring this down to something usable.

in the end the "amp works less" is a marketing gimmick. I think its best to avoid shopping anywhere that tells you something this dishonest.

for noise purposes, its may be better to have the gains set at a lower setting.

Remember, you can't spell geek without EE.

Just kidding; I couldn't agree more. I get pissed when the sales people, even at somewhat reputable places, try to pull the "you put more into the amp you get more out" game.

- Jon, BSCS

 

[snoopdan 5,000+ posts]

In the amplifier game, "the candle that burns twice as bright lasts half as along" as well as "cant get more energy out than you put in" is not a concept that sales people want you to be aware of.

- snoop, ABCDEFG

 

[thch 10+ year member]

what is brilliant is asking "if line drivers increase the amp's power, why don't amp makers build a line driver into the amp?"

silence.

 

[qtipextra 5,000+ posts]

In the amplifier game, "the candle that burns twice as bright lasts half as along" as well as "cant get more energy out than you put in" is not a concept that sales people want you to be aware of.
- snoop, ABCDEFG

I agree. It's a good thing I never buy from dealers, or anywhere there are sales people.

 

[espguitarist91 10+ year member]

considering my crappy head unit has 1.5v outs, would it be a good investment? I know it wont make it louder.........The amp wouldnt have to work as hard, but would that mean less current draw?

 

[squeak9798 5,000+ posts]

of course its better to have your gains set lower. adding a line driver is all about lowering your noise floor. s/n ratio= signal to noise ratio.
my linear pa2 does 36 volts, unclipped.

But if there is no noise with the higher gain setting, then you are gaining nothing by adding the line driver (other than possible noises the line driver may add to the signal). And if you have noise with a higher gain setting, then that's a problem with the amplifier and not the signal voltage. Most well designed amplifiers should still be silent (audibly) with a pretty high gain setting.

 

[squeak9798 5,000+ posts]

considering my crappy head unit has 1.5v outs, would it be a good investment? I know it wont make it louder.........The amp wouldnt have to work as hard, but would that mean less current draw?

You missed thch's post.

The amplifier will work an equal amount. 1000w or power output, is 1000w of power output. And the efficiency of the amplifier is not dictated by the gain setting. The amplifier has to work equally "as hard" either way, as this again is not dictated by the signal voltage input.

So no, the amplifier will still have the exact same current draw regardless of the signal voltage input. If the amplifier is 65% efficient at a given output level with a given load.....this will not be affected by the signal input level.

The only possible difference between a higher signal voltage and a lower signal voltage is a decrease in noise from the amplifier (see my previous post). Assuming your headunit has adequate voltage to allow the amplifier to output full power (which I'm assuming it does, since most amplifiers will make full power with as little as .2V), and assuming there is no noise from the amplifier with your current gain setting......then a line driver will do absolutely nothing for you.

 

[helotaxi 5,000+ posts]

The amp wouldnt have to work as hard, but would that mean less current draw?

Amp has to work just as hard. If the gain is set to make max power it doesn't matter if it is set to do it with a 4V signal or a .04V signal. It will draw the same current and it will make the same power.

 

[espguitarist91 10+ year member]

my bad for being an idiot. Thanks for the help.

 

[o. l. t. 10+ year member]

I have Audio Control products so I do not use an external line driver. I don't really see how anyone can run a system without SOMETHING Audio Control so voltage should not be a problem //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

It's a little tricky to adjust out my XS to my EQT's and run them inline and hit the magic number on voltage, but doesn't take TOO long to get it adjusted correctly.

 

[squeak9798 5,000+ posts]

I don't really see how anyone can run a system without SOMETHING Audio Control

Pretty easily. I've done it everyday for about 8 years now.

//content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif//content.invisioncic.com/y282845/emoticons/moon.gif.9d317aec3339ffe7fde0638df52c628a.gif//content.invisioncic.com/y282845/emoticons/fart.gif.9285a21c4a53b1a914c9dedbfcf9d894.gif

 

[helotaxi 5,000+ posts]

I don't really see how anyone can run a system without SOMETHING Audio Control so voltage should not be a problem //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

It's pretty easy really. I just got rid of my EQTs because they no longer fit in with my system design. Unfortunately AudioControl is still stuck in the 80s as far as the system layouts that their components fit into. I'm not sure why anyone would not run time alignment these days, unless they are not into SQ, and if you are running any kind of acitve setup, it quickly becomes prohibitively expensive and takes a prohibitive ammount of space to use Audiocontrol EQs.