New amp/subwoofer install not hitting...

[undergrounddlz]

Hello guys, new to this site.

Anyways, so I had this system installed in my 06 Cadillac STS by Best Buy..

2 Kenwood KFC 12" Subs + SoundStorm Evolution Amp + Kit + Sub Box

The amp/subs are currently wired under this config:

http://www.sonicelectronix.com/product/img/subwoofer_wiring/2_subs_SVC_8_ohm_2ch_bridged.jpg

The head unit is stock, Bose system. The auto tech wired the in-line converter into the front speakers, and he said he was getting a good signal for the in-line converter. Amp is getting power, however, the system is just not hitting very hard... should I rewire the amp/subs a different way? At one point the auto tech geek squad guy tried doubleing up the + and - leads on the amp, then running the cords to the subs... if that makes any sense.

I'll admit I'm a little rusty since I've been in the military for four years, and haven't been messing with amps/subs till I got out..

Thanks to anyone for any suggestions on where to start.

Alex

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[keep_hope_alive Premium Member]

Thanks for serving, bro.

The subs are wired correctly, you want a 4 ohm load when bridged.

The amp is weak, and the output capability will be limited. Consider it has only 40A of fusing, limiting power input to 560W RMS and output power to 280W RMS, total. Despite the ratings, it's not a high power amplifier. For the same price, for example, a Boss AR4000D wired to 1 ohm is capable of a legit 1,000W RMS. Both are cheap amps incapable of meeting "rated" power, but the Boss has been dyno'd for 1kW.

That's not knocking you or your selection. It's to give you some perspective and help give you a reasonable expectation.

The challenge with tapping speaker outputs of a Bose system is that they may not be full range. Your tech should have ran test tones and check output levels between 20Hz and 100Hz. if output voltage was constant, then you would know there wasn't a high-pass filter on the speakers. Also note that your sub may be out of phase with the speakers (since it has a LPF on it). all crossovers affect phase. You can try swapping phase on the sub (reverse polarity) and see if that helps.

End take-away is that the combo won't rattle your skull. The STS has a pretty stout amount of metal in the trunk which works to block bass in the trunk. Rear deck speakers also limit output and clarity because they are manipulated by the sub (like a passive radiator).

Feel free to ask other questions about the system. Ask the installer about the tests ran and if he tested multiple frequencies between 20Hz-100Hz on the speaker output with the DMM.

 

[undergrounddlz]

Thank you keep_hope_alive.

That is an excellent screen name for a site like this, because car audio can be very frustrating at times..

The thing is, I'm getting like absolutely nothing out of these subs right now...

What I was referring to earlier in my post, when I mentioned the auto tech attempting a last ditch effort to fix the system, basically I think he wired it this way which is different from the way I tried wiring it today in more of a daisy chain fashion.

http://s2.postimg.org/ge7lfups9/Amp_Wiring_Diagram.jpg

(Edit: This was taken from the manual for my subs)

I will say that after he wired it this way, I left Best Buy and drove back home to my apartments. Tried adjusting some knobs on the amp, and it was actually hitting good! But, I was in a residential area so stopped and didn't want to mess with it anymore. So basically today I rewired the sub box because the way I did it the first time was not very professional. Wanted to use female crimps, etc. so that is done. Didn't have enough sub cable to try this config, but I would you like your opinion?

Also, the auto tech made a note of saying he tested the RCA output, and he specifically selected the front speakers to provide a better output for the converter. However, eh, I guess the struggle shall continue for now.

Alex

 

[Jeffdachef 5,000+ posts]

Thank you keep_hope_alive.
That is an excellent screen name for a site like this, because car audio can be very frustrating at times..

The thing is, I'm getting like absolutely nothing out of these subs right now...

What I was referring to earlier in my post, when I mentioned the auto tech attempting a last ditch effort to fix the system, basically I think he wired it this way which is different from the way I tried wiring it today in more of a daisy chain fashion.

http://s2.postimg.org/ge7lfups9/Amp_Wiring_Diagram.jpg

(Edit: This was taken from the manual for my subs)

I will say that after he wired it this way, I left Best Buy and drove back home to my apartments. Tried adjusting some knobs on the amp, and it was actually hitting good! But, I was in a residential area so stopped and didn't want to mess with it anymore. So basically today I rewired the sub box because the way I did it the first time was not very professional. Wanted to use female crimps, etc. so that is done. Didn't have enough sub cable to try this config, but I would you like your opinion?

Also, the auto tech made a note of saying he tested the RCA output, and he specifically selected the front speakers to provide a better output for the converter. However, eh, I guess the struggle shall continue for now.

Alex

The main point he was making is that Your Factory bose amp has a built in EQ/crossover that basically kills off EVERY bass frequency going to the door speakers to protect the speakers, if you are getting signal from that, you basically are getting the same chopped off signal.

Yes if you have a bose setup there should be a factory amp inside that you have to bypass and get the signal before that amp, not tap off the speaker lines.

 

[undergrounddlz]

The main point he was making is that Your Factory bose amp has a built in EQ/crossover that basically kills off EVERY bass frequency going to the door speakers to protect the speakers, if you are getting signal from that, you basically are getting the same chopped off signal.
Yes if you have a bose setup there should be a factory amp inside that you have to bypass and get the signal before that amp, not tap off the speaker lines.

Thanks, ok now I completely understand what was meant.

Before I even decided to take the car to Best Buy, I tried splicing into the stereo itself (yeah stupid but I didn't know any better). Stereo has no built in amp.

The auto tech said he tried to splice into the wires coming from the Bose factory amp to the Bose sub mounted on the top of the trunk. Apparently he wasn't getting enough signal with that (I don't know what his testing method was.. I imagine he used some kind of device), which is why he had to splice into different speakers instead.

So much of this isn't making any sense, because like I said the system was hitting with that initial config at one point.

I think I will try the initial config I left Best Buy with, as that was the only thing that was actually working at one point, before I got **** about the sub box wires and decided to redo them.

If that doesn't work, then I suppose the EQ/crossover theory would hold true, even though it still wouldn't make sense because the system was hitting like I said...

Alex

 

[Jeffdachef 5,000+ posts]

Thanks, ok now I completely understand what was meant.
Before I even decided to take the car to Best Buy, I tried splicing into the stereo itself (yeah stupid but I didn't know any better). Stereo has no built in amp.

The auto tech said he tried to splice into the wires coming from the Bose factory amp to the Bose sub mounted on the top of the trunk. Apparently he wasn't getting enough signal with that (I don't know what his testing method was.. I imagine he used some kind of device), which is why he had to splice into different speakers instead.

So much of this isn't making any sense, because like I said the system was hitting with that initial config at one point.

I think I will try the initial config I left Best Buy with, as that was the only thing that was actually working at one point, before I got **** about the sub box wires and decided to redo them.

If that doesn't work, then I suppose the EQ/crossover theory would hold true, even though it still wouldn't make sense because the system was hitting like I said...

Alex

The built in amp is somewhere hidden in the deep dark crevices of your vehicle. Make sure your subs are wired in phase.

 

[undergrounddlz]

The built in amp is somewhere hidden in the deep dark crevices of your vehicle. Make sure your subs are wired in phase.

Yep, in the trunk behind the carpeted panel stuff.. looks like I'll just have to take another wack at this in a couple days when I can acquire some more 16 awg.

Worst case scenario sell the equipment and chalk it up as a loss. Feel as though I've wasted more time as apposed to money with this whole endeavor, waiting 5-6 hours for the auto tech to finish installing everything.. //content.invisioncic.com/y282845/emoticons/*******.gif.a649d21efc0d1fd4890a6428166586c1.gif

 

[Jeffdachef 5,000+ posts]

Yep, in the trunk behind the carpeted panel stuff.. looks like I'll just have to take another wack at this in a couple days when I can acquire some more 16 awg.
Worst case scenario sell the equipment and chalk it up as a loss. Feel as though I've wasted more time as apposed to money with this whole endeavor, waiting 5-6 hours for the auto tech to finish installing everything.. //content.invisioncic.com/y282845/emoticons/*******.gif.a649d21efc0d1fd4890a6428166586c1.gif

well thats why you dont go to best buy... 5-6 hours... jesus a one armed hobbyist can do the job in that amount of time with less errors.

 

[keep_hope_alive Premium Member]

It's possible you wired the subs out of phase. Double check polarity and even try swapping one.

Sent from my SM-G900V using Tapatalk

 

[dev199505]

Another possibility is your box where did you get it abd is it ported or sealed

Sent from my LGMS330 using Tapatalk

 

[undergrounddlz]

I've got an update for you guys.

Alright so, I acquired more 16 AWG sub wire yesterday, got the wire ready, stripped and crimped connectors on for the amp. Wired to the subs under this configuration.

http://s2.postimg.org/ge7lfups9/Amp_Wiring_Diagram.jpg

The system is actually working, and hitting rather well! I'm satisfied, with the exception... it appears as though when I hit my gas pedal the power to the subs will cut out... however, when I'm sitting in traffic at a red light, the subs are hitting fine! Its as soon as I hit my gas pedal in drive that the system cuts out. If I'm in park the system is fine, heck even if I'm in park and I hit the gas pedal it is fine.

So, after a little research online, I'm thinking perhaps the car is taking power for more important functions in acceleration and reducing power to the amp.

Perhaps a capacitor is in store..? Any thoughts on this?

Thanks for the replies, this has been a constant work in progress but we are getting closer.

 

[undergrounddlz]

Another possibility is your box where did you get it abd is it ported or sealed
Sent from my LGMS330 using Tapatalk

I'm using a sealed box, this is what I purchased.

2 Kenwood KFC 12" Subs + SoundStorm Evolution Amp + Kit + Sub Box

Thanks.

 

[dev199505]

Just road noise drowning out your sub. Need to get some sound deadning

Sent from my LGMS330 using Tapatalk

 

[dev199505]

I'm using a sealed box, this is what I purchased.
2 Kenwood KFC 12" Subs + SoundStorm Evolution Amp + Kit + Sub Box

Thanks.

Your stuff is very low level. Not even entry at this point. So you wont get much out of it. Good news is you can only go up from here

Sent from my LGMS330 using Tapatalk

 

[undergrounddlz]

Thank you Dev199505,

I went to a pro audio shop in town today (not Best Buy..) and consulted with some of the guys there about the issues I've been having. From what I've been able to tell now, it would appear as though like you said "road noise" is contributing to the issue. The output signal we spliced into from the front speakers is becoming modified by some kind of noise reduction system in the vehicle.

I brought my previous hypothesis to the attention of one of the pro audio guys, thinking sound was being cut off to the amp in the acceleration process, this theory is no longer valid in my eyes. Because when I'm driving the subs are still hitting, the bass is just not near as powerful as when I'm stationary. Meaning the spliced output to the line-out is sustaining EQ modifications. He expressed to me the system should only be getting more power in the acceleration process, because the alternator is essentially revving up.

Would anyone happen to know if this product could help fix the issue?

CL-RLC - Car Audio - OEM Interface - System Expansion - JL Audio

Thanks.