Aftermarket System Help : Bass dims on acceleration/increased speed

Truck: 2016 Tacoma TRD OR Double Cab
(had JBL system, now all aftermarket)

System: Idatalink, high end new Kenwood double-din, 5 channel amp (4 gauge wire), all new speakers and sub.

Problem: Bass gets quiet under acceleration and at speed. It's more noticeable under acceleration. Only time is sounds right is when I first start up the truck. Not sure how to test this issue. Only thing I've tried is an different sub because that's all I have around.

Any questions or answers appreciated!

 

Its probably voltage drop. Try upgrading the "Big 3" wires, adding a capacitor, or getting an HO alternator.

 

More info on the system would help. If bass is dropping during acceleration only, sounds like alternator can't keep up.

How many watts you pushing to that sub?

 

Don't get a cap.

Check your voltage, see if its dropping.

Any engine noise when accelerating?

 

I have wanted to do this, but I am weary about warranty issues. I know if it is done right it won't cause an issue but what if an unrelated electrical issue were to occur? Wouldn't toyota say it is because of this?

 

Hu: Kenwood Dnx893s

Amp: JBL Club 4505(45W @ 4ohm and 500W @ 2ohm)

Sub 1: JL 10TW3-D4 Dual 4ohm 400W rms
Sub 2: JBL GTO1214 12" dual 4ohm 350W rms
Both wired to 2 ohm
I forgot to mention that bass gets cut at higher volumes too. I realize how hard I am pushing these but the 12 was in my last car and it was way louder.

Let me know other important details you would like to help find a solution.

 

Before doing H\O alternator try running 4 gauge connection between alternator post and positive battery terminal, could help.

 

Would a multi meter on any 12V source while driving suffice?

I will test the noise on the way to work today.

*Edit: On the way to work, I turned the volume all the way up and listened to static out of the tweeters. It seemed to increase only slightly and hit a peak. It's hard to say with engine noise and road noise though.

 

Thank you for the reply. I am curious if there are some natural electric issues with this truck. I have seen other users say that the cab fan speeds will fluctuate at idle when the engine adjusts rpm. I suppose that would point to a voltage drop. Does higher gauge wire help current flow steadier?

 

Another thought I have is how did the stock system not have these issues?

 

I was just wondering the same thing. Maybe your FI steals it all when accelerating/driving? Maybe some other device? It's completely counter-intuitive to expect lower output from an alternator as it spins faster. Typically they make more power at higher RPM, but I understand this is a canbus truck.

Not too sure I understand your sub situation though. So you're running both subs off this amp? Could you be showing a 1 ohm load to the amp? If you have both coil systems configured to 2 ohms, then you're giving the amp either a 1 ohm or a 4 ohm load...neither is ideal. If you're at 4 ohms, you're only getting 320W from that amp. If you're at one ohm, you're killing the amp with death.

If this is a 4 ohm load, neither of the subs is getting the power it deserves either. Maybe consider removing one of them? If you intend to keep them both, test resting impedance (disconnected from amp) & report back. I suspect the load is too great (too low impedance). This could cause your problem.

I think you're right in testing the electrical before going further. See if there's a voltage drop as you accelerate and drive - compared to idle. Do it with the radio off and on. Maybe that will tell you something. I still think there's something to the impedance you're offering your amp though. The numbers just don't work out in your favor. 2 different subs off the same sub channel isn't generally done either although I'm not entirely sure what effect that would have on the big picture aside from some possible cancellation (not the problem you're experiencing).

 

Sorry for the confusing information. I have only ran one sub at a time to see of there was a difference between the two.

I am not knowledgeable on canbus systems, do they regulate total output voltage from alternators? Another thought I have is the Idatalink is connected to the canbus. I wonder if that is affecting voltage since that is the only link between Hu and vehicle power.

 

Hmm. That doesn't look like anything the stock charging system couldn't handle. Sadly I don't have a whole lot to offer. If it were me I would start with the "big 3" upgrade and go from there.

EDIT: just saw something else. You say you have them both wired to 2 ohm. Are you sure the amp can handle (2) 2 ohm loads?

 

Yes, 500w @ 2ohm and 350w @ 4ohm

 

What size power and ground wire are you running and where is your ground connected to?

 

4 gauge, it is the largest size the amp may accept too. Ground is on seat belt bolt under back seat.

 

I was getting dimming until the big three and took my grounds straight to the chassis making sure to clear all paint so a solid ground was established. I was running 4 gauge but ran 1/0 up to a power splitter into 4 gauge. People thought I was flashing lights at them before this.

 

Doesn't the seat belt bolt to the chassis?

 

It does but mine is galvanized and the mount is painted

 

Good point Jimmy. If the paint/coatings aren't removed you won't have a solid ground. Still though - less power on acceleration is weird sauce. Ever put a meter on it OP?