HEEEELP with audio amps and low voltage

[Marky]

Hello to everyone, I've tried looking every where for the answers to my crisis but no one has the same issue.

2004 Tahoe 5.3 v8 4x4 LS non-bose

I have a 4 channel amp and a mono block class d amp hooked up and when the bass hits my 4 channel goes to a whisper volume.

I have tried the big 3 and now my voltage is around 10 volts. Battery is a XSPower D3400 that I got in January this year. I changed the Alternator in July of 2015. I did notice that my positive coming from my alternator was corroded and the sleeve was all brittle. The end that was connected to the alternator was stiff while the end that was connected to the battery was very flexible.

0/1 gauge for power and ground to a 2 way distribution block and out as 4 gauge to the amps. I'm grounding the to the seat bolt right underneath the back seat seatbelt buckle.

Please help. Any suggestions are greatly appreciated.

 

[Hyperion]

Depending on how big your mono amp is it might be drawing a lot of amperage and pulling power from your 4 channel. You might need an extra battery in the back and/ or a high output alternator. I'd suggest buying one of those cheap cigarette lighter voltage meters so you can watch the voltage while playing the stereo but I'd bet you are dropping into the low 11s or high 10s when a bass note hits.

 

[Marky]

I'm going to change the alternator tomorrow and see if that helps some. It's only a 65x4 RMS pioneer amp and a Kenwood 900x1 RMS mono class d amp. When I turn my stereo up even the sub amp cuts out. The alternator is going to be a 140 amp from AutoZone. It's already under warranty so I just have to take it off and exchange it.

 

[Hyperion]

That's not a whole lot of wattage but it sounds like you are dropping voltage really bad. 140 amp alternator might not be enough.

 

[Marky]

I'm going to go over all my wires and reroute some of the big three. There's so many threads on doing the big three that I just chose one and its probably the culprit. I'll update tomorrow after everything.

 

[Marky]

I changed the alternator and I'm still getting really low output. Even with all accessories turned off. Could a amplifier cause the problem. The 4 channel is classified as a pure class A http://www.pioneerelectronics.com/PUSA/Car/Amplifiers/GM-X1024

 

[ISU-152]

Amps can certainly go out. They're very complicated with complex circuits and resistors. Used to run a 2 channel 600w pioneer for rears and a 4 channel Sony 1200 watt running two 12's no problem off a 3.1L beretta. There is an underlying issue here and probably due to wiring . Most likely grounds...are they painted?

 

[Marky]

No the grounds are sanded off. Originally I had a bevla bb2000.1 installed but one day after 7 months of no issues the amp fried and started smoking really bad. That's when I started noticing my voltage going down. I did buy the pioneer 4 channel from a pawn shop so I'm going to remove it and see if it makes any difference in voltage.

 

[ISU-152]

Even if they aren't painted give the grounds a good sanding and move one ground to a new spot.

If that doesn't help you need to start eliminating things...like disconnecting one amp at a time and seeing the results

 

[ISU-152]

No the grounds are sanded off. Originally I had a bevla bb2000.1 installed but one day after 7 months of no issues the amp fried and started smoking really bad. That's when I started noticing my voltage going down. I did buy the pioneer 4 channel from a pawn shop so I'm going to remove it and see if it makes any difference in voltage.

Also what are you bridging? + channel 1/2 to - channel 3/4? Try reversing that as well

So - channel 1/2 to + channel 3/4. Or dont bridge at all

 

[Marky]

Also when I changed my alternator I removed all the wires from the big three to see if maybe one of them was causing the issue but things didn't change.

 

[Marky]

Currently it's the pioneer 4 channel and a Kenwood kac9501. Rockford fosgate 3 ways in the doors connected to each channel on the 4 channel. Soundqubed hds3 12 connected to 1 ohm on the Kenwood.

 

[ISU-152]

Also when I changed my alternator I removed all the wires from the big three to see if maybe one of them was causing the issue but things didn't change.

Does your truck have the positive wire terminal block that splits into two? One goes to starter and one for everything else? I've seen starters carrying a draw which can be quite high....so could try just removing the starter cable and see it the system will run. Few options to go over tonight lol

 

[Marky]

I'll check that tomorrow, along with removing my amps and see if maybe one of them is gone bad. The pioneer is a class A, so it stays on constantly. If turn the stereo on and have the volume at zero I can hear the fans on the amp running even though I don't play anything through it.

 

[YukonXL04]

Have you checked voltage with a meter at the battery and at the amps? Also have you checked resistance of the main power wire?

Also check the sub with a meter. Almost sounds like the sub is wired too low for the amp. Maybe the coils are messed up?

 

[Marky]

After doing some research I found out that AGM batteries can go into a deeply discharged state that will read low voltage. Also that a traditional battery charger won't charge a AGM, cause a AGM needs to be on a trickle charge for about 6-8 hours. So I'll be dropping off my battery at Autozone in a bit in hopes that it fixes some of the issue.

 

[massivespl]

After doing some research I found out that AGM batteries can go into a deeply discharged state that will read low voltage. Also that a traditional battery charger won't charge a AGM, cause a AGM needs to be on a trickle charge for about 6-8 hours. So I'll be dropping off my battery at Autozone in a bit in hopes that it fixes some of the issue.

If your battery is resting below 12.6v and it's an AGM battery it's messed up. For charging it You can buy a simple battery tender charger for $25 that charges AGM batts and then goes into float mode when fully charged. You just plug it in and forget it. Lol

 

[NC-Tahoe]

Are you running a big capacitor tied to the power side of the sub amp? If not, this will stop it from sucking all the power from the rest of the car (the capacitor will dump the needed power and save the stain on the rest of the system). My headlights use to dim on big bass hits - since the added cap no issues.

Also, check to be sure there is no ground loop. Ypu should have your amps grounded to the same bolt, if possible.

 

[massivespl]

Are you running a big capacitor tied to the power side of the sub amp? If not, this will stop it from sucking all the power from the rest of the car (the capacitor will dump the needed power and save the stain on the rest of the system). My headlights use to dim on big bass hits - since the added cap no issues.

Also, check to be sure there is no ground loop. Ypu should have your amps grounded to the same bolt, if possible.

Car audio capacitors are junk! they bottle neck the system,wayyyy better to get a ** alt and AGM batts.

 

[Marky]

Just got the battery back and it's bad. I'll be buying a duralast gold tomorrow and a second battery within 1 1/2 just for audio purposes. But for now I'll just use this one for audio since it's still going. I just can't believe a XSPOWER d3400 would only last 8 months in Texas heat. I guess I'll be using a different brand cause the big 3 kit that I bought was also XSPower and it got all brittle and frayed.