So lets trouble shoot.
Does it still sound harsh if you disconnect the sub from the amp but leave the amp connected to the car amp speaker connections? If yes then the amp is somehow affecting the Bose system. Try using a different line level converter.

Does the harshness vary with the gain of the subwoofer. Perhaps there is active equalisation that is not expecting or designed to work with much greater bass.

btw your pictures did not post

 

Sorry. I edited the original post. Also the front door speaker lines that I tapped into might not be full range. Bose lists them as "woofers".

When I disconnect the RCA from the subwoofer end, the sound signature is restored to factory.

It is hard to tell with the gain. Turning the gain up 1/5 way is already causing the subwoofer to overpower all of the speakers. I don't have much range to play with to see if it increases harshness. It seems like the Bose AudioPilot2 mic picks up the additional low frequency, causing the Bose processor to try to counter it by increasing the high frequency as an attempt to closer match factory sound parameters. Hence the reason I turned AudioPilot2 off. There is still harshness present, just not as much.

The low range from the sub is somewhat muddy. I don't expect top notch low range from a powered sub, but I did expect better. My crossover is adjusted low in addition to the low gain, but muddiness is still somewhat present. Perhaps it is because the front door speaker signal isn't full range as required by the high-pass input?

Would the rear speaker line be a better signal source?

 

I have an Audi with the Bose factory system. While it is a different car than yours, I would assume the systems are quite similar. (i.e. I have the AudioPilot feature)

My Bose system consisted of the following speakers:

Front Tweeters (L & R)
Front Midrange (L & R)
Front Midbass (L & R)
Front Center
Rear Doors Tweeter & Midrange (L & R, passive crossover)
Rear Surround (L & R)
Subwoofer

All of those speakers were active crossover at the Bose amp, except for the rear door tweets/mids which have passives.

In my car, the front midbass are crossed over rather high. I tested them with an oscilloscope and 40Hz test tone and it was a flat line. That means, at least in my car, the Bose front outputs were not suitable for tapping signal for an aftermarket subwoofer.

Second issue.... Bose factory EQ. It is very common for factory systems to have equalization applied to them. This can be a challenge for us trying to upgrade because we ideally want a flat response from the factory system to feed our aftermarket gear. I was curious about the frequency response of my Bose system so I ran a test with REW while bypassing my DSP's adjustments. Here is what I got:

Yikes! Bose is doing a lot of EQ with that signal.

Here is what I got when I ran the same test but bypassed the Bose system completely by plugging directly into my DSP via the AUX inputs.

The second picture is almost exactly what we want to see. A nice, flat response going into the aftermarket system.

So, as you can easily see, Bose does a heck of a lot of factory equalization to the signal before it leaves their amplifier. It is a safe bet your system has some serious EQ applied, too. That's how Bose operates; it's like their calling-card.

Another issue in my car is that the Bose subwoofer is located in the rear deck, and therefore the Bose engineers decided to make it fade with the rear speakers. So if you use the fader in the head unit to play only the front speakers, you lose the subwoofer output. Have you tested your Bose system to see if the bass is stronger when all speakers are playing vs. just the fronts or rears? If there is stronger bass when the rears are playing, you might want to consider tapping those for your sub.

 

Bose calls my dash speakers both midrange and tweeters, but they seem to be crossovered high as well. That is probably not an option to be tapped for subwoofer.

My front door speakers are "woofers" that seem to be crossovered for mid and low range. Probably wasn't a good idea to tap that either because my subwoofer sounds a bit muddy. When I fade fully to the rear, I do lose some bass, but the front door speakers are still partially active.

The rear door speakers is most likely full range. At least Bose states that. I do not have a dedicated woofer. Most of the low range comes from the front door speakers and the rear door speakers.

 

It sounds like the rear outputs are a better candidate for tapping the bass signal for a sub.

I assume your subwoofer amp has an internal crossover? How do you have that set?

 

Front door speakers are probably the best to tap to feed your sub (as you have done). Do you think that maybe the doors are playing softer and that the imbalance with dash mid/tweeters are making them seem harsh when in fact they are doing the same thing as before? It doesn't make sense for the dash speakers to actually change.
What crossover setting are you using on the sub amp?

 

Did you try bypassing the Bose amp outputs altogether? My car also has a Bose system, but mine had two subwoofers. When I first added a sub & amp I tapped into the factory subs. When I installed the processor, I tapped into the signal from the front channels coming from the HU.

 

I thought that was the best idea too. I looked at the diagrams and couldn't find the specific wires to tap into from the HU output to Bose processor/amp. Diagram 920-5C in my original posts shows the connection.

 

Any more suggestions?

 

Be brave. To bypass the Bose amp, start cutting the wires (one by one) shown as 1A thru 1X and I bet they are the line levels feeding the Bose amp. By cutting one by one, you should be able to figure out which 2 are front left, front right, rear left, rear right. Then you need to figure out + and -. Audio Tools cheap app for iphone and android works pretty good.

Not sure if this will accomplish anything. If the EQ is in the amp (which is probably the case) and not coming from the headunit, then yes, this would defeat the Bose EQ.

 

Yeah, I see your point. I was able to figure the connections out by going through the factory service manual. I ended up finding the colors corresponding to the correct wires as well as double checking by counting the contacts on the pin connectors.

 

I'm not really sure what the problem is.

In my car, I did a full system replacement so I never even tested how the Bose speakers sounded. We used 7 of the Bose amp outputs into my Audison BitOne.

Front TW (L/R)
Front Mid (L/R)
Front Midbass (L/R)
Sub

I easily found the wires by looking in an Audi repair manual. Everything was color coded, and had specific locations in the wire harness.

We disconnected and removed all of the front Bose speakers, and the rear deck speakers. We disconnected, but left in place, the Bose rear door speakers.

I have had no serious issues, other than trying to deal with the wacky Bose factory Equalization which I posted pics of earlier in this thread. It's not such a bad problem, however.... because I tend to use my iPod directly on the BitOne Aux input. Better sound quality that way by keeping the signal out of the OEM system altogether.

I'll also be adding a MoBridge DA1 preamp soon so I can bypass the Bose factory amplifier completely. I'm hoping this will remove that Bose EQ curve.

 

When I added a amp and subs to my '99 Olds Intrigue, I just used the Scosche SLC-4 LOC and it worked great. It sounded fantastic. I could not have been happier with the small investment I had into the setup.

Point being, I tapped into the wires going from the head unit to the Bose amp and fed the RCA outputs to my aftermarket amp (Powerbass ASA800.2) which powered the subs, and OMG!!! It sounded phenomenal.

Bose is infamous for odd equalization, but I gotta say, when combined with powerful sub-bass it worked out quite well.

 

I would like to try tapping into the output from the headunit before it reaches the Bose amp. Unfortunately those diagram 920-5c that I posted have no information on what wires I should use. I see the harness and connector, but no idea what the wires do.

 

Ever consider to bypass all?

 

I have not seen the CX-5 in person, but from the looks of the picture on their website the head unit should be easily removed. You could install an aftermarket head unit and then run your own amps and speakers.

I don't see any Climate controls on the head unit. You are really lucky. I wish I had the option of replacing my head unit. But no chance of that in an Audi with MMI.

Alpine even has a picture on their website of a 2013 CX-5 with one of their 8" Nav screens installed.

 

I have thought about that, but it is too much to commit to as of now. Also the vehicle settings (locks, lights, auto wipers, etc) are integrated into the factory headunit. Those that change the headunit in the higher trim levels with more adjustable features will lose all ability to change the settings.

 

Maybe just bypass the audio/video side?

 

Tried swapping to the rear speakers as signal source. I grabbed the rear full range output from the Bose amp/processor.

Same results with harsh highs and missing mids. Though I noticed the subwoofer's bass less muddy and signal is much lower. Once again, as I disconnect the wires to the amp/subwoofer while everything is playing, the 9 speaker Bose system sounds normal without the harsh highs and missing mids.

Can the integrated Line Level Converter in the powered subwoofer play a roll? Would switching to a dedicated LOC make a difference?

 

Can the integrated Line Level Converter in the powered subwoofer play a roll? Would switching to a dedicated LOC make a difference?

That would be the next thing to test, I think. Try another converter.

 

Insights?

 

So you are trying to tap a factory audio signal from a speaker, but keeping that speaker still connected and playing? Can that even work? (I'm asking honestly because I simply don't know)

The only experience I have is with tapping a factory amp signal into a DSP and replacing all of the speakers for the system. This method works great in my current car with Bose.

 

From the diagram, it looks like there are two shielded groups of four wires each (1A1C1D1F in one group, 1S1U1V1X in the other) than run from the head unit to the amp. The marketing materials say the amp is digital, but still, it looks to me like those could be analog lines for front left, front right, rear left, and rear right. If it was sending a digital stream, I'd only expect to see two lines from HU to amp.

Fade the system completely to the front and to the left, then play a 60hz tone through the system and see if you can pick up an AC voltage reading between any two of the pins in one of those groups with a multimeter. If so, you've probably found a pre-Bose low-level signal you can tap.

 

I have a 2014 Mazda6 and ended up checking this myself, because I'm planning to install a JBL MS-8 and wanted to know where I could tap to get a full-range pre-Bose signal.

Oddly, the CX-5 is slightly different than the Mazda6. Yours has 2H on the amp that is tied to 1L on the headunit and to the instrument cluster, while on the 6, there's just 1L from the HU to the instrument cluster. My amp also has a terminal 2D that runs to the accessory position relay that your amp doesn't appear to have. Weird.

Anyway, using a 60Hz test tone, I was able to see a max of about 1.8V with the HU volume at Max on these lines I mentioned. I was using a really old analog meter, though, so the number may really be 2.0V, since that's more standard I think.

Using the balance and fader controls, I was able to determine they map this way:

front left - 1A and 1C (first pair in harness)
front right - 1D and 1F (second pair in harness)
rear left - 1S and 1U (third pair in harness)
rear right - 1V and 1X (fourth pair in harness)

So, you should be able to run from these to the RCA input of your amplifier and get a full-range signal that won't mess up whatever the Bose amplifier is trying to do, hopefully.

 

other options: Deaden the hell out of those doors! they need it.. ( Yes I have installed an audio system in a cx-5 )
Maybe you're playing the sub with inversed polarity, losing lower midrange detail due to cancellation..

Why buy a car with bose? lol

 

Maybe you're playing the sub with inversed polarity, losing lower midrange detail due to cancellation..

He mentioned in his original post that he'd tried with the phase switch on his amp at both 0 and 180 degrees, so that's not it.

Why buy a car with bose? lol

In my case, it wasn't optional.

 

I know this is an old post, but I was wondering "SayNotopistons" if you ever resolved this and was Josby correct? I would assume he was but I am doing research on my 2016 CX5 now.