Added Subwoofer, not getting the results expected

[KyleF]

Hi everyone, new here but not new to playing with my cars.



I had an old Alpine PDR-M65 (650W RMS 2Ohm)and Kick L712” (4Ohm DVC wired to 2Ohm at the box) with box sitting around my house that was originally in an ATS I had many years ago. Randomly, I decided it would be cool to put it in my Tahoe now that my kids are a bit older and using the 3rd row isn’t as much of a concern as it used to be.

With that said, I did some basic research to see how people were tapping into the wiring to get a signal. The rest is pretty common. I decided to follow this video:

Video Followed

So, to make this short I basically did exactly as you see in the video except, I used a Kicker 46KSILOC2 Line out converter to tap into the wires on the B-Pillar.

Kicker LOC used

Being how I am, I tend to check the function of things as I go. So, after installing the LOC, I tested the voltage at the RCA cable. I saw the AC voltage varying, but staying under 1V. Thought this was low, but worked for the guy in the video. I made the decision to move on as I saw it was providing a signal. Guy in the video didn’t show output voltage

To no surprise, once everything was hooked up, it seems I have a signal issue. With the remote gain know to max and the gain on the Amp at max, it just isn’t “loud” like you would expect a L7 to be when supplied by 650W and setting in a decent enclosure. When the volume was increased, it also seems to reach a level where it cuts the signal further as if it is intentionally dropping it.

First, it seems like the low voltage is just too low for the Amp to bring up. Knowing I am supposed to have close to 650W into 2 Ohms, I would anticipate to see Voltage at the Amp output on the order of 3oV+ give or take. I am not seeing that, If I remember correctly, I was seeing 19V max. This would be on the order of 200W of output and it kind of sounds that way being this is a power-hungry speaker. This is vintage 2014 L7, so I believe the speaker has an RMS rating in the 700W. All of the components have been kept inside, climate controlled, out of the sun, etc. I saw no issues with equipment condition. IU have done some reading, but I can’t see where others have reported signal issues

With that said, is the spot I tapped already a low voltage signal? If it is, should I avoid an LOC and just get the speak to RCAs?

Should I tap somewhere else to get a higher voltage signal?

Is this just a bad LOC. I have used it with the ground connected and not connected (LED indicator on/off respectively) with no change in signal.

Is there a possibility the LOC is bad?

The LOC I have is not adjustable, do I need a model that is?

 

[K2 Kaiju]

The spot you tapped has a processed signal that pulls bass to protect the speaker at high volume. If you tap the harness right at the Bose amp (its in the back driver side by the jack/tools), you will get a better sub signal. This post may help find the tap...

Post in thread '2015 Tahoe LTZ aftermarket amp and sub install' https://www.tahoeyukonforum.com/thr...market-amp-and-sub-install.79920/post-1626415

 

[KyleF]

The spot you tapped has a processed signal that pulls bass to protect the speaker at high volume. If you tap the harness right at the Bose amp (its in the back driver side by the jack/tools), you will get a better sub signal. This post may help find the tap...

Post in thread '2015 Tahoe LTZ aftermarket amp and sub install' https://www.tahoeyukonforum.com/thr...market-amp-and-sub-install.79920/post-1626415

Thanks, I can check the tap there and take voltage readings.

 

[K2 Kaiju]

Try just replacing the front corner speakers with the Kicker KSC270s first as it makes a noticeable improvement in the stock bass response. I decided to skip the sub after doing mine, and the space savings is a big bonus on the short body. Cheap and easy under an hour job. You can always add the sub later if you need more...

 

[Doubeleive]

Hi everyone, new here but not new to playing with my cars.



I had an old Alpine PDR-M65 (650W RMS 2Ohm)and Kick L712” (4Ohm DVC wired to 2Ohm at the box) with box sitting around my house that was originally in an ATS I had many years ago. Randomly, I decided it would be cool to put it in my Tahoe now that my kids are a bit older and using the 3rd row isn’t as much of a concern as it used to be.

With that said, I did some basic research to see how people were tapping into the wiring to get a signal. The rest is pretty common. I decided to follow this video:

Video Followed

So, to make this short I basically did exactly as you see in the video except, I used a Kicker 46KSILOC2 Line out converter to tap into the wires on the B-Pillar.

Kicker LOC used

Being how I am, I tend to check the function of things as I go. So, after installing the LOC, I tested the voltage at the RCA cable. I saw the AC voltage varying, but staying under 1V. Thought this was low, but worked for the guy in the video. I made the decision to move on as I saw it was providing a signal. Guy in the video didn’t show output voltage

To no surprise, once everything was hooked up, it seems I have a signal issue. With the remote gain know to max and the gain on the Amp at max, it just isn’t “loud” like you would expect a L7 to be when supplied by 650W and setting in a decent enclosure. When the volume was increased, it also seems to reach a level where it cuts the signal further as if it is intentionally dropping it.

First, it seems like the low voltage is just too low for the Amp to bring up. Knowing I am supposed to have close to 650W into 2 Ohms, I would anticipate to see Voltage at the Amp output on the order of 3oV+ give or take. I am not seeing that, If I remember correctly, I was seeing 19V max. This would be on the order of 200W of output and it kind of sounds that way being this is a power-hungry speaker. This is vintage 2014 L7, so I believe the speaker has an RMS rating in the 700W. All of the components have been kept inside, climate controlled, out of the sun, etc. I saw no issues with equipment condition. IU have done some reading, but I can’t see where others have reported signal issues

With that said, is the spot I tapped already a low voltage signal? If it is, should I avoid an LOC and just get the speak to RCAs?

Should I tap somewhere else to get a higher voltage signal?

Is this just a bad LOC. I have used it with the ground connected and not connected (LED indicator on/off respectively) with no change in signal.

Is there a possibility the LOC is bad?

The LOC I have is not adjustable, do I need a model that is?

yaa that video is pretty much use less
your going to want like a LCI2 pro and connect it to the amp output in the rear drivers side as noted above
using the LCI allows you to restore the bass signal and tune it somewhat as desired. that will also give you some bass control if your amp does not have one already.
a simple line converter is going to result in sounding like doggsh*t

 

[KyleF]

Try just replacing the front corner speakers with the Kicker KSC270s first as it makes a noticeable improvement in the stock bass response. I decided to skip the sub after doing mine, and the space savings is a big bonus on the short body. Cheap and easy under an hour job. You can always add the sub later if you need more...

I am sure you mean well, but this is a sub/box/amp I have had sitting around. Not looking for advice on what component speakers or otherwise to add. Not overhauling the system, just adding some stuff I have sitting around.
I never thought the factory bass response was poor. Do we have the same factory system? I have had people *think* I have sub installed. I say think, because I know the factory sub is there, but they are talking about another aftermarket installed previously. I just wanted more punch.

 

[KyleF]

yaa that video is pretty much use less
your going to want like a LCI2 pro and connect it to the amp output in the rear drivers side as noted above
using the LCI allows you to restore the bass signal and tune it somewhat as desired. that will also give you some bass control if your amp does not have one already.
a simple line converter is going to result in sounding like doggsh*t

You seem disgruntled in your post, are you aware? Do you mean to sound like that?

The issue was phasing. Checked back to the taps, was correct, but swapping "+" and "-" at the box fixed it (Mostly). As mentioned, there is a cut in the bass at a certain volume. I do plan on verifying the signal at the back and possibly switching the taps. I am still not seeing the peak voltage I would want to see at the speaker outputs, but otherwise performance is as expected now.

The LOC is just fine for a stock head unit streaming Bluetooth. The weak link in signal quality there is not the LOC. My only question is where does the DSP occur. Is there any built in to the head unit or does it all take place at the Bose amp? I am probably not digging in that far when I just want to add a little punch and vibration to the system. I will follow up when I get a chance to tap into the signal in the rear.

 

[Doubeleive]

You seem disgruntled in your post, are you aware? Do you mean to sound like that?

The issue was phasing. Checked back to the taps, was correct, but swapping "+" and "-" at the box fixed it (Mostly). As mentioned, there is a cut in the bass at a certain volume. I do plan on verifying the signal at the back and possibly switching the taps. I am still not seeing the peak voltage I would want to see at the speaker outputs, but otherwise performance is as expected now.

The LOC is just fine for a stock head unit streaming Bluetooth. The weak link in signal quality there is not the LOC. My only question is where does the DSP occur. Is there any built in to the head unit or does it all take place at the Bose amp? I am probably not digging in that far when I just want to add a little punch and vibration to the system. I will follow up when I get a chance to tap into the signal in the rear.

The signal filtering happens at the amp, bose is well known for doing this and they do not publsh specifications.
not only that but they also split the outputs so speakerphone output is on one speaker, backup sensor signal is on another, vehicle alerts are on another, etc
the video is nearly useless aside from a couple pointers of where to run wires, where does the remote wire go? and he knows the output sound is going to be like listening to a am radio which is why he doesn't mention anything about it.
if you are going to use the stock radio and amp then you need bass restoration
or use a adapter behind the radio that bypasses the bose amp entirely
like a pac ap4-gm61 which gives you rca pre-outs from the stock radio
using $10 parts is going to get $10 results, that's just how it goes especially when dealing with a modern system

 

[KyleF]

The signal filtering happens at the amp, bose is well known for doing this and they do not publsh specifications.
not only that but they also split the outputs so speakerphone output is on one speaker, backup sensor signal is on another, vehicle alerts are on another, etc
the video is nearly useless aside from a couple pointers of where to run wires, where does the remote wire go? and he knows the output sound is going to be like listening to a am radio which is why he doesn't mention anything about it.
if you are going to use the stock radio and amp then you need bass restoration
or use a adapter behind the radio that bypasses the bose amp entirely
like a pac ap4-gm61 which gives you rca pre-outs from the stock radio
using $10 parts is going to get $10 results, that's just how it goes especially when dealing with a modern system

Bro, you are off base and the video worked fine, sound quality is fine (after reversing polarity). The only issue is that of the original post, not seeing the output voltage that should be there for a 650W Amp going into a 2Ohm load. What I am gathering here is that it may have to do with DSP pulling bass levels to protect the speakers.

I think you need to understand not everyone is trying to install a competition sound system. I had a 10year old amp, box, and sub sitting around. Just want a little punch added to the factory system (that many others felt was impressive before) for S and Gs. The real issue here is the voltages and how that plays into power output. You went from there into insulting a video, making false claims (it doesn't sound like AM Radio) and talking about buying $150 or $400 items... for what?!?!?! never once mentioned how that would help voltage.

When I get time to investigate the voltages at the rear, pre-amp, I will report back what they look like and if I choose to move my tap, I will report how it affected the output voltages.

 

[k_arnold72]

Do you have the Bose system? What exactly are you working with in your truck? What year and model?