Gain, Level, Input Sensitivity,

[Alpine2005 10+ year member]

I have installed many systems other the years. But ever really understanded the gain setting.

Do all of these mean the same thing? Gain, Level, Input Sensitivity

Some people say that the gain is like a Volume on the amp but some people say that you must match the gain with the HU's preamp outputs voltage.

Which one is true? Or are both true?

All the system i've install, i tryed to match the gain with the HU's voltage.

Click to read more...

 

[jsloan10 10+ year member]

Read this for the full story-

http://www.caraudio.com/vb/showthread.php?t=63933

 

[Alpine2005 10+ year member]

so which is true? match the gain with the HU's preamp outputs voltage

 

[jsloan10 10+ year member]

It is definitly not a volume knob, the idea is to perfectly match the pre out voltage of the HU to the amps sensitivity to eliminate as much distortion and noise as possible.

 

[Alpine2005 10+ year member]

how would i find the Voltage of my amps?

like the example amp on the JL website has a voltage 17.3v x 2 = 35.6

 

[jsloan10 10+ year member]

Ignore the ratings for their amps and subs its model specific, you need to substitute your equipment in its place.

All you need to do is play a 50hz tone and turn the gain up untill the desired voltage is acheived, 1khz for mid/tweet amp. voltage is verified at the speaker terminals using a DMM whith the speakers disconnected

I'll figure out the target voltage but I need to know what speakers the amp is going to run and what are the voice coils ohm ratings

for example

Sub amp

-brand, model and rated output.

Sub woofer

-brand, model, voice coils nominal impedance (ohms) and RMS power handling.

You basically want to set the voltage output of the amp to match the voltage handling of the speaker.

for example a SVC 4ohm sub rated for 300 watts RMS would have a target voltage of about 35 volts, so you would tweak up the gain until you got 35 volts on the outputs.

Watch this again-

http://www.jlaudio.com/tutorials/Input_Sensitivity/Input_Sensitivity.html

Its very important you get a good understanding of it.

 

[Alpine2005 10+ year member]

ok let say i'm going to be running a PG Octave-R 5:0:1 mono amp rated 300rms x 1@2omhs and 150rms x 1@4ohms to power a 12" Alpine SWS-1242D DVC 4ohm rated 300rms, 900peak

so what would be the voltage setting?

 

[Johnny Drama 5,000+ posts]

ok let say i'm going to be running a PG Octave-R 5:0:1 mono amp rated 300rms x 1@2omhs and 150rms x 1@4ohms to power a 12" Alpine SWS-1242D DVC 4ohm rated 300rms, 900peak
so what would be the voltage setting?

300w x 4ohm =1200 take the sqrt =24.49v

 

[Johnny Drama 5,000+ posts]

I did that wrong.....

300 x 2 = 600 = 24.49v

 

[jsloan10 10+ year member]

Thank's for picking that up for me jntar, I was to busy to answer for awhile. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[AVSTANG02]

I told my dad to set my gains mother ****er whips out the multimeter and tells me to **** off.

apparently the fact i couldnt understand simple algebra really pissed him off.