maybe too little power?

Hey fellas. Any one ever had this situation happen to them?

I am running a soundstream vir-7860 touchscreen/dvd player deck............4 gauge power wire, clean connections, ground wire I used a grounding connector block from work, ground off the paint before I impacted it.    2 farad cap......Rockford Fosgate punch 1000.1 pushing 2 JL W3 V2     12 inch subs running on a 2 ohm load.   The other amp is a MTX   250.2  that I have wired to   2  6x9 xplodes and 2 6.5 xplodes.   1 inch dual dome tweeters are running straight off the deck.       Here is what is happening.

The deck goes to 30.  When I have it on 25 and turn the gains up on my amplifier the cap drops from 13.8-14.2   down to 12.5 and lower.   When I have the deck on 15 and turn the gains up I get alot better play from the subs and tweeters, it goes alot louder and sounds better.  Either way I go though I think I need a bigger altenator because when I crank it up I get this crazy boom.boom.boom out of the subs that is not in "tune" with the song.  Some times when It happens the deck turns off, other times I have to turn the deck off.  Does anyone think this to be a power problem?  I used crimp caps on the back of the deck and everything looks clean.  there is a ton of rca inputs and outputs coming off the back of the deck for gps, camera, etc that dont have plastic sleeves over them. Any good ideas on what I can do to improve the situation is greatly appreciated.  also what is the name of the inline filter to get rid of the altenator noise, Right now mine is down right Nasty!   thanks.  mike. 

It was just going crazy at random times but most of it was when I turned it up around half to 3 quarter if I could make it there.  I found the problem though, fixed it at lunch.  being the retart I am i forgot to crimp the ground wire on the deck.........now its beating very nice, and no more hissing sound from the altenator, at least not near as bad.  Isnt that strange!

hi m8

are u sure the power cable is big enough?  if you run a 2 ohm load it doubles current draw

do you know the reason for the gain control?

hi

if you've got 1250w rms then the power cable assuming the length is an average 10-13ft should be AWG 0 and same for the ground wire.......if you have a 2ohm load and the voltage remains constant it will double current draw.  i think the relevant ohm's law formula's are on here.

the gain adjustment is to allow the amplifier to produce it's maximum output when the source unit is sending it's maximum output to the amplifier. if the gain adjustment is not set correctly either the amplifier will never reach it's max output because it is not configured to receive a sufficient level of input signal voltage or the amplifier will prematurely clip the audio signal because it is configured to receive too high a level of input signal voltage.

the best way to set the gain is to take real time measurments with an ossiloscope...... 

enjoy

I do have a 20 M Oscilloscope, a function generator, and a dmm.  I understand what your saying about the clipping because in school we have made small op-amps and I have observed clipping and some of the other stuff that goes on inbetween adjusting the gains and so forth.  So If i want to set the gain so that I am getting the most out of the amplifier when the head unit is giving the most it can give all I really need to do is take a measurement from off the rca's and take a measurement from the amplifier right?  Set it so that the head unit is 3 quarters of the maximum volume and then just crank the amp up until it goes just before clipping?  What kind of a test tone would I send through it?  Any help is appreciated.   I am a 7 quarter itt tech student for computer and electronic engineering, so I do understand alot of this stuff, but im no pro.  any help is appreaciated.