New build is having an issue and I can't seem to troubleshoot it

[Buck 5,000+ posts]

So I did another try with my gains and the DMM and found that with help from the bass boost settings in my h/u eq I can get to 31 volts with only about 20% gain. I also made sure I was getting the full 2V out of the h/u and I am. Something about it still just doesnt sound right at all. The sub moves more but not by much. I am starting to really regret ever wanting to upgrade.

It seems to me that if everything is 100% hooked up correctly, then this is a head unit RCA voltage issue and possibly somewhat of a box layout/location issue. I tend to lean on this being mostly a signal voltage issue.

I'm not being sarcastic and be careful if you do this, but have you tried playing with the gains just by listening to what the sub is doing? And I'd definitely check the sub and make sure the wires haven't been pulled out on one coil or anything like that, and I'd also check the sub coils themselves and make sure they're reading the ohm they should be.

There's only so many things before you figure this out. If you have a headphone aux jack to RCA splitter, you could play sine waves from your phone and see if maybe your RCA's themselves are damaged. Sometimes RCA's break inside, and that can cause a low-volume issue. The idea with that is to skip your radio and RCA's in the vehicle and plug up another signal source to see if the amp moves the sub any differently. If it plays differently, then you'll know there's an issue with that related equipment.

 

[LucaBrasiMN]

I wouldn't give up on it. Sound is difficult. You have a decent little system there. I wouldn't run the bass boost too high on the radio, and I'm not sure if I have a valid explanation. I've just always had issues that way, may cause distortion.

Have you checked to see if your sub is wired at 1 ohm?

And like I say too, the boxes in trucks like that can be difficult to get right or to get the best sound out of a single 12 like that. I mean that as a fairly long time box designer. Pickup trucks are basically the hardest every day vehicle to design enclosures for. The space is more awkward, usually, and the cabin is big and a lot are wider than they are deep/long.

I'm not sure if I missed it, but what's the voltage at your amp when you're trying to play the sub? Knowing that would possibly immensely help you figure this out. If you're on a stock electrical system, you'll know if the amp is pulling current by the voltage on the power wires going into the amp. You should drop voltage somewhat, especially if the vehicle is just idling.

I'd also check your fuse under the hood, and make sure that hasn't come loose. I've had a lot of those come loose before, just where the fuse is screwed/bolted on.

I have triple checked that I wired it to 1 ohm. I went - to - to amp and + to + to amp. I don't know if the way I did it is right though. I have 2 short wires connecting each terminal on the sub, neg and pos, then on one side, another set of wire sharing the space in the terminal then going to the amp. I used RFs wiring wizard. This does seem like the issue as everything works fine and no weird smells or power issues, just no oomph at all.
I will check the fuse under the hood, I put in a 100A as the amp spec sheet says it needs but my last build, the much smaller amp had a 200A fuse. Maybe I should try putting in that fuse?
When you say to check the voltage at the amp when the sub is playing, what do you mean? I have checked the speaker terminals without the speaker wire in them to set the gain and I have checked the tip of the rcas and I am getting the expected 2V from the headunit.

 

[LucaBrasiMN]

It seems to me that if everything is 100% hooked up correctly, then this is a head unit RCA voltage issue and possibly somewhat of a box layout/location issue. I tend to lean on this being mostly a signal voltage issue.

I'm not being sarcastic and be careful if you do this, but have you tried playing with the gains just by listening to what the sub is doing? And I'd definitely check the sub and make sure the wires haven't been pulled out on one coil or anything like that, and I'd also check the sub coils themselves and make sure they're reading the ohm they should be.

There's only so many things before you figure this out. If you have a headphone aux jack to RCA splitter, you could play sine waves from your phone and see if maybe your RCA's themselves are damaged. Sometimes RCA's break inside, and that can cause a low-volume issue. The idea with that is to skip your radio and RCA's in the vehicle and plug up another signal source to see if the amp moves the sub any differently. If it plays differently, then you'll know there's an issue with that related equipment.

Yeah the first thing I did was fire it up and adjust the gains with a tone playing. It still barely moved. I just check the voltage around the power and ground and everywhere I get the same thing, about 12.5ish volts. The end of the rcas that would be plugged into the amp get 2V. 1.98ish to be exact. The fuse is tight and not blown. I am adding an extra ground to the batt as we speak. I got another set of rcas on the way to test those but that will be a couple days. When I check the ispeaker wires coming out the box with the DMM I get about .8ish ohms. So that seems to be right.

 

[LucaBrasiMN]

Could using these reducers be bottle necking me?

 

[MattinMO]

Terrible ground sir. Doesn't even look like you sanded the paint down to bare metal. Self tapper grounds = no beuno
Get you a good frame ground with a bolt, sand any finish down to bare metal. Your current draw is limited by a shotty ground.

 

[LucaBrasiMN]

Terrible ground sir. Doesn't even look like you sanded the paint down to bare metal. Self tapper grounds = no beuno
Get you a good frame ground with a bolt, sand any finish down to bare metal. Your current draw is limited by a shotty ground.

Ignore the first pictures in this post. I have redone most of that. The ground is sanded bare with proper nuts and bolts now and still same issues.

 

[MattinMO]

Ignore the first pictures in this post. I have redone most of that. The ground is sanded bare with proper nuts and bolts now and still same issues.

What is your signal source? Aftermarket deck, dsp, loc, ?
Do you have a voltmeter ? Have you checked your draw?
What methods did you use to adjust the settings on your amp?

 

[LucaBrasiMN]

What is your signal source? Aftermarket deck, dsp, loc, ?
Do you have a voltmeter ? Have you checked your draw?
What methods did you use to adjust the settings on your amp?

All of this has been discussed in this thread at some point. Pioneer headunit, used DMM to check voltage throughout system, 12.5 everywhere including at amp. deck preamp outs 2V, 1.9 at deck and at amp. Ohms are right, dvc 2ohm wired to 1. Wires into amp about .9 ohm. I followed multiple videos on how to set the gain.

 

[Buck 5,000+ posts]

Do you have a different sub to try by chance?

I still lean on it's radio RCA voltage. The box you have might be hindering sound too, but the sub should still move around a good bit.

You should get a headphone jack to RCA splitter and plug your phone into your amp and play tones to see if you can make your sub play that way.

Not very expensive and it'll help you troubleshoot any amp by letting you use your phone as a signal to bypass any potential signal source problems.

 

[LucaBrasiMN]

Do you have a different sub to try by chance?

I still lean on it's radio RCA voltage. The box you have might be hindering sound too, but the sub should still move around a good bit.

You should get a headphone jack to RCA splitter and plug your phone into your amp and play tones to see if you can make your sub play that way.

View attachment 33163

Not very expensive and it'll help you troubleshoot any amp by letting you use your phone as a signal to bypass any potential signal source problems.

Yeah the box isn't perfect but I'll worry about that when i figure out what's going on. I got a new set of rcas on its way today so i will try that when i get home. I also just got a 3.5 to rca adapter from Amazon that says it will be here tomorrow so I'll try that tomorrow. If these don't fix it then i ran out of things to try. Could see if a local shop can troubleshoot it but that's expensive.

 

[LucaBrasiMN]

Tried the new RCAs. Maybe a tiny, tiny bit of a difference but still not even close to sounding right. Will try the aux rca adapter tomorrow.

 

[LucaBrasiMN]

Do you have a different sub to try by chance?

I still lean on it's radio RCA voltage. The box you have might be hindering sound too, but the sub should still move around a good bit.

You should get a headphone jack to RCA splitter and plug your phone into your amp and play tones to see if you can make your sub play that way.

View attachment 33163

Not very expensive and it'll help you troubleshoot any amp by letting you use your phone as a signal to bypass any potential signal source problems.

So buck, I got the aux to rca today and it definitely is WAY better. I can actually see the sub move with it. 40hz tone actually has some bass to it now. So knowing this, do you think a line booster is all I need or should I start shopping for a new headunit? Appreciate your help man, almost there!

 

[Popwarhomie 5,000+ posts]

I didn't read through all this but make sure your headunit subwoofer level is turned up.

2 volt outputs is not an issue.

 

[LucaBrasiMN]

I didn't read through all this but make sure your headunit subwoofer level is turned up.

2 volt outputs is not an issue.

I have tried this. The problem is the headunit is about 9 years old which is where I think my problem lies. I can get the voltage to my desired 31ish with the bass boost settings turned all the way up and the gain about 50 percent and even with that it just had no oomph at all. The aux rca adapter was the only thing I have tried so far that gave me any sort of decent bass. I think the headunit ia just old and crappy but I dont know.

 

[Buck 5,000+ posts]

I would just get a new radio if you could.