2014-2018* Mazda 6 (and Mazda 3) w/BOSE Full System Breakdown/Analysis

I've been wanting to do a somewhat thorough upgrade of the audio system of my 2016 Mazda 6, but had a really hard time finding much info about the system in the models with BOSE and the newer head unit. So, with the little info I managed to find as a starting point, I decided I'd take a crack at figuring out everything I needed to know myself.
This video documents the various testing procedures that followed, as well as covers analysis of the results. I figured at least a few people other than myself would find this information useful so I decided to clean the video up a bit and share it here.
The video has a companion thread over at the Mazda6Club forums that you should also look at if you want even more information that isn't completely covered here: forum.mazda6club.com/electric...
* This information definitely applies to the 2014-2016 models, I'm fairly certain this information applies to the 2017 model, and am taking an educated guess that this info applies to the 2018 model.
BONUS 2016-2019 CX-5 Basic Wiring Labels (Unconfirmed): i.imgur.com/wNoHrGI.png
Timestamps for your convenience:
0:00 Intro/Background
1:18 Extended Background
3:26 Applicable Vehicles & Vehicles Specifics
5:59 Section Breakdown
7:25 Companion Forum Thread
7:48 Connections From Head Unit to BOSE Amp
9:00 Single Channel Connected Discovery/Test
10:09 4-Channel Wire Pairs Pinout
10:32 Head Unit/TAU Signal Type/Polarity Test
11:53 Test Signal on the O-Scope
12:19 Explanation of Different Signaling Methods
15:09 Differential Signaling Discovery
16:35 Audio Test Sanity Check
16:56 Channel Polarity Pinouts
17:12 Stereo, Balance, and Phase Test
18:55 Head Unit Signal Analysis (Intro)
22:04 Head Unit Signal Analysis (White Noise Results)
23:45 Head Unit Signal Analysis (Song Results)
24:25 Head Unit Signal Analysis (Bass Roll-of Debunk)
24:53 Feature Retention (Head Unit Controls)
28:03 Feature Retention (Calls/Google Assistant)
29:05 Feature Retention (Chimes/Alert Tones)
31:08 Potential to Remove BOSE Amp Entirely
32:49 Conclusion

[@zkzeroxvirus]

Fantastic video my man, props to you. Thanks for taking the time.

[@Alanyepez123]

Great investigation, very in depth and helpful. Great job!

[@pljubas]

Great video! I had removed bose amp and speakers at my 2015 6 and replaced with JL Audio amps and Focal speakers. Great sound improvement!

[@johnathonlevesque3784]

Thank you, I was looking for so long on what to do.

[@prooflessExistance]

Thank you. I just wanted to add an underseat sub and your video is the only thing I've found so far that has provided me some info. I'm pumped up to give this a go now! Thank you for your time and sharing us your expertise :) You shall have my follow.

[@prooflessExistance]

@ oblivioncth I've been the Mazda6Club and on your forum. I have a question that I wanted to get a quick answer to. I'm going to be attempting this tomorrow. I'm very new to this as well but I have some DIY knowledge. i.imgur.com/Lyuef1R.png The Rear L & R from your picture here, can I do a Y split, have 1 end go to the sub and the other noraml to the Rear L & R Bose speakers? Thank you :)

[@fishstick617]

I added an underwear subwoofer and I couldn't hear it because my Bose systems bass was louder

[@junkname9983]

Tap the lines to the sub's amp like this: Black=Front Left+, White=Front Left-, Red=Front Right+, Green=Front Right-; accessory switch to the red/black wire on the other connector. Easy peasy.

[@jonallsop7502]

Amazing work

[@ChallengerAndyOfficial]

Holy man this is /really/ in-depth.

[@oblivioncth]

Haha lol didn't see you checked this, thanks. I tend to be very much "if you're going to do it, do it right", so I pass on a lot of stuff but the things I do go for I often go pretty hard with (though sometimes to my detriment >

[@troydavenport9244]

Thanks heaps for this bro.

[@RNBYT97]

I seriously bow down to you! I just like you have been looking for SOMETHING on my 2014 for years to work around the Bose system! I chose the 2014 specifically to install my own head unit. Im curious to see what you do to splice into the speaker channels before the amp. Im trying to find a way without cutting/hacking the harnesses.

[@oblivioncth]

Since I was replacing the whole system, I just cut into the end of the stock wiring that plugged into the BOSE amp and attached RCA ends to each of the 8 wires needed for the 4 channels and the hooked those into my 5-channel amp. I'd have preferred to keep the stock wiring clean but there doesn't exist a breakout connector or harness I could butcher for the 3 cables that go into the BOSE amp. The closest thing is the PAC-MAZ-OEM2 but that also has a hi-lo converter and since the signals are already low level, dropping them further would raise the noise floor, distortion, and hiss. Considering this and the fact that I don't have a 3D printer, my only real option was to just cut into the factory cable. BOSE amp is already sold off on eBay and everything works great.

[@fishstick617]

I had best buy put a sub amp in my 2018 3 touring with the Bose system and I can only hear bass from my subwoofer when centerpoint is activated.. do you think they just tapped the wrong speakers?

[@burns985]

In my 2014 CX5 my radio doesnt turn on. I changed the radio and its still the same. Is it a fuse of bose amplifier? Appreciate some help

[@axi6ne8us]

Audio channel out.. help! So yesterday I changed out the driver side speaker with the Alpine S-S65 since I wasn't getting sound and thought the OEM speakers went bad. Well I'm having the same left channel issue. Hardly any sound from the Alpine speaker. What's the next thing I should look for? A short somewhere or maybe the left tweeter in the dash is gone also? Could it be an Amp issue? I got a 2015 M3 iGT sedan

[@shadow1419]

Great video! Did you ever test the output of the head unit for maximum volume before the signal clips?

[@oblivioncth]

I never did this purposely but I didn't notice any clipping with the volume in the high 40s/at 50 and it caps out at 63. So up to that point at least it doesn't clip

[@85nager]

I need help! I have a 2019 Mazda 6 GT. Has bose amp, how do I patch in so that I can install a line converter????help

[@someguy8419]

I'm really confused, what do I do if I want to connect this into an amp or dsp that does not support differential signal input? You mentioned a simple circuit to convert it but never went over it and I can't find any info on it. Do I just connect the negative wire for the amp input to chassis ground so that the amp doesn't seen the inverted signal?

[@skymakai]

found this while trying to determine why the front left twiddler in my 2014 Mazda3 seems to have stopped working. I'm guessing it may just be the amp.

[@cliffordguy7406]

Yeah i love my 2015 just changed to a double din pioneer

[@baljitot]

well done man.. 👏 best explanation so far.. thanks for your time.. questions, i know that your test for the signal wire is before the input of bose amp, is it after the TAU or mazda w/ bose doesn't have a TAU? because i have a 2017 mazda 2 that has TAU, and if i tap signal source from output of TAU, i definitely have bass roll off under 45Hz (i've test it with tone generator)

[@oblivioncth]

Thanks. Interesting, I guess they do it a bit differently in the 2s (I don't think they even offer those in my region). My vehicle doesn't have a separate TAU and has no rolloff before the BOSE amp, and I didn't think the earlier 6s/3s that have the separate unit did either but its possible they do. I can only go off what I heard from one other owner and the fact that I believe the amp model number between the 2014/2015 and 2016+ amps for the 6 are the same, but its possible there's a software or regional difference.

[@baljitot]

@@oblivioncth thanks again man for your reply.. i kinda miss on your video so i just want to make sure, the signal from the head unit that you tested is it low level or high level? i kinda see 50mV or something on your oscilloscope..

[@edoubleist]

Thank you for making this video! This gives me inspiration and guidance. I have a 2024 Mazda CX-5 and I’ll be measuring the signals with an oscilloscope like you did to detect which wires are audio pre Bose amp. How would you measure the audio signal pre Bose amp to determine the bandwidth? I’m also curious how flat the signals are as well.

[@oblivioncth]

I suppose you could try using a laptop over AUX or something in order to play a increasingly lower/higher frequency pure tone (with the output muted so you don't torture yourself) until the measured output is distorted in order to determine the lowest and highest frequency that the HU can properly output and then you'd know the bandwidth before the amp is taken into consideration. Though there would be the concern that one of the extents might actually be limited by your playback device and not the HU itself.

[@rodiellezcano2024]

Awesome video, thanks for the detail analysis it helps to understand how does the stuck system works. I own a 2016 CX-5 GT with Bose audio system, Would all this be the same scenario (in terms of wire scheme) in my case? I am looking to replace the BOSE amp with a 5-channels amp.

[@oblivioncth]

I can't be 100% sure since I don't have access to a 3rd gen CX-5, but I was able to find the wiring diagrams for it online. The plugs are all the same shapes and sizes and the wiring colors are mostly the same. The most differences are the colors on the largest and second largest cable that hold connections to the stock speakers, car power, ground, etc. The 16-pin (6 of which are not present) connector with the 4-channel low-level output (that is most likely what you're interested in) and Audio-pilot mic input, 0920-515A in the 6, is actually exactly the same other than that the one wire for the Audiopilot mic that is black/red in the 6 is yellow in the CX-5. As the video states, these wires are annoyingly unlabeled, but I really doubt they would move around which pin was which channel yet keep the colors all the same so I'm 95% sure the wiring for the smaller 16-pin connector is exactly the same. Obviously if you pull out the connector and the 6 (3 top, 3 bottom) terminals on the right of it are actually in use, or the wire colors are drastically different, then stop because then it may not be the same. The diagrams I found are for the 2018 but I don't think they've really changed anything since the 2014. If you want to tap something from the other 2 connectors (i.e. 12V ACC/Turn-on signal power, stock speakers, stock ground, etc.), let me know and I'll look over those connecters as well, because their connections are at least labeled in the diagrams.

[@rodiellezcano2024]

@@oblivioncth Appreciated your feedback and Yes if you don't mind specifying the rest (as i think i will need them) like Remote Turn-On and Constant 12v.

[@oblivioncth]

@@rodiellezcano2024 Here. It isn't as elegant as the one's I did for the 6, but I filled in the colors and labels so it should suffice. Make sure the wire colors match what is in your car at the BOSE amp as while the site I got the diagrams copy off of said it was for the 2016-2019 CX-5, the diagram itself is labeled for the 2018 CX-5. This is normal with Mazda, as for example the diagams I had to use for the 2016 6 were labeled as being for the 2014, its just a little odd that in this case the diagrams are dated newer than the vehicle instead of older. They almost always change colors when the functions change so if all the wire coloring is the same for you then that site was correct and the 2018 diagrams apply to the 2016 as well. One oddity is that on the CX-5 there is a signal for the I-Stop function going to the amp. I can only imagine it is to limit the output power of the amp while the engine is off so that your battery doesn't drain too much, but I can't be sure. I doubt it will actually affect the I-Stop system itself, but you may want to test drive with the amp unplugged just to be safe. i.imgur.com/wNoHrGI.png

[@troydavenport9244]

2013 GJ Wagon with the Bose system has the amp under the passenger seat. Driver door distortion is an easy fix. Search "Mazda 6 speaker fix" by Darius.

[@henrygodwin5896]

Do you think it’s possible to put this amp in the previous gen Mazda? My 2011 amp failed and I picked one of these up fairly cheap to see if would work. The connectors are exactly the same, but I don’t get any sound out of the speakers…

[@Th3M4larky]

So with volume + equalization before the bose amp, does that mean is the head-unit doing a pre-amp? Does that conclude the signal is digital?

[@oblivioncth]

Not sure exactly what you mean lol. The signal is 100% analog. The only things the headunit can change is the voume and balance, all factory EQ is done through the BOSE amp including the optional settings you can turn on in the headunit. I suppose the headunit does technically do a bit of pre-amp as it does directly manipulate the magnitude of the audio output, though even at the loudest setting the voltage is still low enough to be considered a line-level signal.

[@framesngrains2933]

Need some help I'm hoping you can give me. I got the '20 CX5 with the Bose system. Should I tap into the speaker wires under the seat or near the glove box? Thanks!

[@oblivioncth]

I haven't been in a CX5 (let alone 2020) and there aren't wiring diagrams for it in particular, so I can't be sure of how its different. I did do a quick drawing of the 2018 CX5 wiring that would probably apply to the 2020 (they only change them ever so often but its never 100% clear what range of years that a particular workshop manual applies to), but as for the physical location of everything I'm not sure. You want to start by locating the BOSE amp, which is likely under the passenger seat or behind the glove box as you noted. Once you find that, reference this drawing to know what connections you want to use: i.imgur.com/wNoHrGI.png You can splice into the cabling at any point in the line (before it gets to another device obviously) so at that point its up to you if you want to follow the cables back up a bit instead of splicing right at the amp.

[@BMWS14B23]

Wow the effort first off is awesome. The question I have is if I just want to add an amp and subwoofer, in a non Bose mx5, could I just get a pack unit and connect the rca’s to the amp, run power to the amp, and get low sound for the sub?

[@oblivioncth]

Yes. From what I've heard despite being made for the 2 Gen Mazda vehicles, the pac-oem-maz2 still works on gen 3 vehicles. I cant be 100% certain though

[@BMWS14B23]

oblivioncth thanks for the help!!!!

[@goodfellagwc8117]

Great post! Is the 2016 Mazda3 with Bose, laid out the same or are there differences? Thanks again for any answer you can provide me as well as for this terrific information!

[@oblivioncth]

The Mazda 2016 Mazda 3 is exactly the same except that there are only 4 speakers in the front so the 2 lines that in the 6 are shared by the twiddlers and tweeters on the front dash only connect to 1 speaker each on the 3.

[@goodfellagwc8117]

@@oblivioncth, terrific. Thanks for responding so quickly! Now I'll have to decide if I want to use a component set up with the tweeters on the dash and the mids in the doors. Will have to figure out the crossover location I guess. But again, thank you so much for everything you've done on this topic! If you have any suggestions, please let me know!

[@caleb3781]

So you'd recommend just the stock setup I get a used mazda 2016 and just upgrade it? You think it'd be worth it to just install only a sub in the back and see if im satisfied?

[@oblivioncth]

The stock headunit is generally best unless you don't mind losing all of the integrated functionality such as oil warnings, door lock settings, etc., but I'd definitely suggest making use of your own amp using the information in the video otherwise. However, just doing a sub is something a lot of people do. For that if you're going to tap pre-Bose amp as described in the video you'll need at least a 1-channel amp, which would then possibly be useless if you decide to do more later. If you think its highly likely you'll only ever have the aftermarket sub, splicing into the rear door speaker wiring and taping into that with a low-pass filter (or sub with built in crossover) is often good enough. For anything more than a sub though, the line-level pre-Bose amp signals are the way to go.

[@11ryn]

Great video, man! Now, I do have question, wondered if you could help. If I want to bypass the stock amplifier, do I have to get signal from the headunit? I currently have a LOC tapped into the rear speakers to get the RCA outputs. Now, if I wanted to completely bypass the stock amp, do I need to get another 4 channel LOC? Then into the aftermarket amp, and then back into the factory amp harness, so I won't have to run cables all the way from the amp to each speaker. And the one that's currently tapped into the stock amp harness would also have to be rewired to the headunit? Did I get that right? I am not sure if I have a TAU behind the glovebox, I have the same 2016 Mazda 6, the harnesses on the passenger side amp look the same as yours.

[@oblivioncth]

With a 2016 6 you definitely have the TAU built into the headunit so don't worry about that. If you want to bypass the stock amp you don't need a LOC at all, which is why I delved into trying to figure things out with the audio system on this car as that's what I wanted to avoid. Sorry if it was confusing exactly what was going into/coming out of what since everything I showed was at the plugs for the BOSE amp, but cable 0920-515A goes between the headunit and BOSE amp and it carries the 4-channel output from the headunit that you can feed directly into your own amp if you splice into it at the end that was going into the BOSE amp and terminate the 8 wires you need with RCA ends (or whatever your amp accepts). You just have to create the ends with each pair for each channel (i.e. black and white is the front left channel) as described in the video/forum post and those can go straight into you amp. Just leave everything else disconnected and make the power & speaker connections to your amp and you're basically done, other than running cables obviously. It ends up being: Headunit -> End 1 (that you don't need to access) of 0920-515A -> End 2 (at BOSE amp under passenger seat) of 0920-515A -> Your Amp's audio inputs I wouldn't recommend reusing the factory wiring for the speakers, but if you're not going to play your system very loud you technically can. If you do this you do not need a LOC for that either, you would just need to splice into 0920-515B & 0920-515C for the wire's going to the speakers (the last diagram in the forum post is helpful for this) and connect those to your amp's audio outputs. Do note though that the factory wiring has the rear deck "Twiddlers" (mid-range) speakers tied together (essentially making them mono) and you can't separate them unless you do your own runs, and you may have to adjust the balance to not have them sound overpowered since you'll have to connect them to both the rear right and left outputs of your amp.

[@11ryn]

@@oblivioncth Thanks for the reply. So I can just take the 0920-515A cables and splice them into RCAs, that's cool. 515A is what comes from the headunit, and 515B and 515C are the outputs to the speakers. Did i get that right? The reason I wanted to reuse the factory wiring is that I wouldn't have to run cables back from the amp into each speaker. It would've been faster to just go into 0920-515B and 0920-515C rather than routing cables through the doors. Well, if I'll replace the speakers I may as well turn up the volume and enjoy them. I've seen different variants, and they were between 60 and 100W RMS. Would you say component or coaxial in front?

[@oblivioncth]

@@11ryn Yes you have that correct with the cables. I can definitely understand wanting the convivence of using the factory wiring, and ultimately I view it as a little less of a sin than most enthusiasts probably do, but the main reason it's a problem and that I mention audio volume is for safety. The factory wiring on 99% of vehicles is usually very small gauge and usually just barely thick enough for the generally low (relative to aftermarket) wattage rating of the factory speakers. For example, the fuse going to the stock BOSE amp is 25A, which means that at the 12.5V the amp runs at it will blow if your power usage is above a measly 312.5W. Obviously there's a big difference between peak power draw and RMS, each speaker size will vary in its draw, and the power drawn from each channel doesn't cause a 1-to-1 change in the amount drawn from the amp input, etc. but just realize that if you put even just a 700W amp in a crank the system up quite a bit that you can draw up to nearly twice as much current through those lines as was ever intended, which is obviously a fire and equipment damage risk. Loudness is subjective, and you can still probably get fairly loud without issue, but I just mention this to be clear since you will technically be in a situation where you can have major problems depending on your usage. When it comes to setup, there's obviously a lot of options with many right answers and lots of subjectivity involved, with restrictions based on budget. I don't remember the power cap of my units but I personally used a 3-way component setup in the front, and a pair of coaxials in the rear doors, while leaving the rear deck speakers stock.

[@tcams76]

Excellent info bro, I have a 2016 Mazda 3 Hatchback W/Bose. Im thinking getting a used OEM Bose spare tire Sub from a (2016 Mazda CX-9) off Ebay. And Im wondering how I tie it into my Bose amp? I dont want to buy a pink elephant. Of course, taking it to a installer is a last option. I just subscribed to your channel.

[@oblivioncth]

The original thread I used as a starting point might be a good reference as that user just wanted to add a sub as well: www.mazda6club.com/threads/2016-headunit-location.386602/. You would need to get a mono amp, feed its input from any one of the four low/line-level headunit output channels I show in this video (or companion form post in the description), OTHER than the front left (since that gets lowered for voice command input) and then just feed its output straight to the spare tire sub. There is no way to connect it directly to the BOSE amp on a 3/6 because the subwoofer output line that is used on the CX-9's version of the BOSE amp is already taken by one of the front door woofers. You could tap directly off one of those and skip the mono amplifier but it would most likely make the front door woofer you choose to tap from sound quieter and you would lose the ability to control the subwoofers volume separately from everything else.

[@bartek010]

Do you know what is the impedance of the front dash speakers? I'm looking for replacement for my 2015 M3

[@oblivioncth]

I'm not 100% sure, but it's my understanding that everything from the BOSE systems is 2 ohm

[@tonycastillo4612]

So to add an amp line out converter i just tap into the grey and blue and pink and light green?

[@oblivioncth]

It can basically be any of the channels you want. Since you are mentioning two pairs of wires I'm assuming that the sub-amp you plan on using has a two channel (left and right) input. In this case just use the left/right set from either the front or back. So either: Left Input - (FL) Black/White Right Input - (FR) Red/Green or (the set you mentioned) Left Input - (RL) Pink/Light Green Right Input (RR) Grey/Blue One thing to keep in mind is that the choice does matter if you use your fader, as the fade is controlled by the headunit, so your sub volume will be lowered if you ever fade the channel(s) its sourced from. This can either be desirable or not. For example, if you're likely to generally fade out the rear and never want your sub faded, source the sub-amp from the front L/R pair, or if you do want the sub to fade with the rest of the rear, then source the sub-amp from the rear L/R. If you don't ever use your fader then obviously this isn't an issue.

[@gtRELIC]

I just wanna hook up one mono amp to a pair of Subs. I want as much low end as possible without losing too much of the Bose system. I'm afraid to try without the LOC but If I'm reading correct that might not be an issue and a LOC may actually make my bass sound worse. Am I reading that correct? I apologize if I sound dim but I'm out of my depth yet determined to learn

[@oblivioncth]

More or less yes. With the LOC you'd be only using a portion of the signal that's going to one of the speakers, having already been somewhat frequency gated by the BOSE amp. The rear door speakers are probably best for this since they're near full range, but if you want the ideal its best to just tap any of the 4 input channels I talk about in the video/post directly and feed that to a mono-block amp for your sub. The only thing worse about it than doing the speakers is that if you're putting your sub in your trunk like most do, obviously the front passenger seat area is a more annoying cable run than a rear door speaker, but its otherwise a simpler (no LOC required, just the amp and sub) and cleaner setup overall.

[@morejelloplease]

did my comment get deleted or was it filtered by spam? i'm trying to figure out more about the fake engine sound piped into the bose amp on the new mazdas. if there's a way to pull a can wire, a vehicle speed sensor wire sent via PWM, or maybe a different wire as there currently is no way to disable what bose calls EHE or engine harmonic enhancer .

[@oblivioncth]

Wow that's wacky. Unfortunately I don't have access to a newer one with that "feature" so I really can't say, outside of replacing the whole amp with a custom one just for that issue, lol.

[@zane812]

Could you go into some small detail with your current system? I see in a comment below you said it cost nearly $4000 and if you could share the details on what you got it would be much appreciated!

[@oblivioncth]

I can find the exact model numbers if needed, but the basic overview is a JL VX1000/5i Amp, 3-way component HAT Unitiy sets for the front left and right, HAT Imagine Convertibles for the rear left and right, and a JLW3v3 12W subwoofer in a sealed enclosure.

[@DaneISGr8]

Hey just found this, thanks btw. If I want to keep the stock system, but add a sub with a mono block amp. Do I just splice in the LOC before the Bose amp? Example the white and black wire.

[@oblivioncth]

Yes, that is exactly what I'd do. However, do not use black and white (the front left channel), because that is the channel used for AA/Carplay/Mazda Nav notification which would mean everytime a notification was played your subs volume would lower, just like the Front Left speakers due when music is playing, and the notification would also be played through your sub (obviously only the low frequencies though). Use any of the other 3 channels and you're fine

[@DaneISGr8]

@@oblivioncth perfect, any pair you would recommend besides the black and white more than another? On another note I stopped half way through my install and noticed the windows wouldn't go up automatically with one touch. Any ideas? Lol the only thing unhooked is the amp. Maybe I blew a fuse. But they still go up if I hold them.

[@oblivioncth]

@@DaneISGr8 For whatever reason whenever you disconnect the battery or it dies, the automatic window feature is disabled until it is reset. If I remember correctly, you have to low the window all the way, then immediately raise it all the way and keep holding up even after it closes for 3 seconds. Then the auto function should work again. As for which channel to use it really doesn't matter. Choose any of the other 3 that your the least likely to ever use the fade feature with since fading that channel would lower your subs volume too

[@DaneISGr8]

@@oblivioncth you the man 😎

[@MilkoObradovich]

Hello, so can I cut an rca and tap into the rear left and right input of the bose amp and feed an aftermarket amp? Full range without bass rolloff and using the aftermarket amp's crossover cut higher frequencies.

[@oblivioncth]

That would work though you may lose navigation/dialogue from AA/Carplay (I'm not sure about stock navigation) if you have them, as I know the voice and notification sounds only come through the left side, and believe only the FRONT left side, though I'm not 100% sure. If you are going to use a 4/5/6 channel amp or bi-amp there is not reason to not take input from all 4 channels. If you are trying to use only a 2 channel amp or something of that sort then you are probably better off taking the front left and right inputs rather than the rear or seeing if you can use something cheap to sum the front right with the rear right and front left with the rear left and then use those as your 2 channel input signal. In theory the front right/left should be identical to the rear left/right and the reason the system even has 4 channels in the first place is some things can be sent to just 1 corner of the car if needed (i.e. navigation cues). If you were considered by the front vs rear signals because I used the rear only for some of the diagrams, fear not. That was only because the scope I used has an absolutely garbage USB driver and takes an absurdly long time to dumb data over USB (hours) and sometimes the process can inexplicably fail. So I did test all 4 channels but only saved data sets from the rears to save time and not keep my car stuck unusable for like a whole day. All BOSE 4 inputs (outputs from the headunit/TAU) share the same, non-EQed, in balance/alignment quality. The rears are typically thought of as the priority to tap if you are going POST BOSE amp since those are close to full range vs the front in that situation, but pre-BOSE amp all 4 channels are fine to use.

[@MilkoObradovich]

kzbin.info/www/bejne/eYuni3h5gL-qpbM

[@oblivioncth]

@@MilkoObradovich as you noted in your video using the PAC isn't ideal becasue you are dropping a line level signal down further so the as a result the noise floor will be a bit higher and its more likely to have issues with hiss/distortion/clipping. I personally would avoid it for use in a semi or full system replacement. However, for just adding a subwoofer I could beleive it works just fine.

[@MilkoObradovich]

@@oblivioncth I thought that also... but it works!!!

[@ronaldchan3401]

yes if your amp accept differential balanced input, otherwise you will have all kind of noises.

[@cruxinterfaces]

Clean Install, if you want to see other great 12 volt videos please check us out.

[@ethancontreras3538]

Hey man! This video rocks! I’m try to but a mono sub in my 2017 6 w the Bose system and I’m wondering where you would tap in for that. I know your is a different year but do you know if those door speakers are strictly subwoofers or if the crossover affects them. If the crossover does could tapping in to the TAU or Head unit itself bypass that?

[@oblivioncth]

I'm assuming you're talking about the front door woofers. They are pretty large, a little under 9" so they're definitely only suited for lower tones. All of the division of frequency is handled by the BOSE amp. The signal coming from the Headunit/TAU is full range and entirely unaltered, so the BOSE amp more-or-less doubles as an active (or perhaps passive, I haven't looked at the internals) crossover. If you tap into the front door speakers directly you'd of course be limited to whatever frequency band they are fed by the amp. The cutoff might be a bit high for a full size sub, since those they aren't quite big enough to be a true sub, but I'm not sure since I've never monitored the output going to those speakers on the original system directly. If you want 100% control on what feeds your mono amp you'll have to tap at the headunit.

[@ethancontreras3538]

Thank you! I can’t believe you replied haha. I’m super new to this, I didn’t know anything about car audio this morning, so bear with me, but I like messing with guitar electronics and want take on a bigger project. The sub is a “12 150watt. The amp is a small 2 channel (kicker DXA125.2) with 125watts out (bridged). Im just wondering how to tap into the head unit channels. I’ve seen some harnesses that adds another five channels that plugs into the head unit but I called a local shop and they said something like that wouldn’t work and that my best bet would be to tap into the wires after the amp and mount the amp in the trunk. I’m not sure if I explained it well enough to them though. What would you suggest?

[@ethancontreras3538]

@@oblivioncth Additionally, the amp has a signal input switch for low and hi input so I’m assuming I wouldn’t need to convert to low, so would I just splice a RCA cable directly into the corresponding wire pair? Or do they have harnesses that run RCA out? Please correct me if anything I said was incorrect. Thx again!

[@oblivioncth]

@@ethancontreras3538 Doing the investigative work on this car was my first real foray into car audio beyond the little bit I already knew, so I actually can't offer a ton of advice outside of what I did. In my case I replaced the entire stock amp so I avoided the complications related to splicing into the existing equipment while keeping it running as is. Tapping off the headunit lo-level signals (which is generally best) for a mono-amp config requires splitting one of the 4-channel outputs form the HU into 2 (one going to the BOSE amp as it does originally, and the other to your new amp). Technically, the best way to do this is a "splitter", which is generally just a box that does some extra massaging of the signal to assure that both outputs of the split are the same as the single output you start with; however, splitters can often get complicated and are often have many more features for other circumstances that are outside the scope of what you're trying to do that I'm not very familiar with. That being said, you can just basically create a "Y" cable by splicing into the two wires that compose any of the 4 output channels from the head unit and just connecting some extras wires to those to create the inputs for your amp (basically just cutting into the existing cable and siphoning off it). Most half-decent audio equipment for years now tends to follow a low output impedance, high input impedance paradigm which allows to you split a lo-level signal like this many times before notable loss occurs; however, technically speaking the BOSE HU doesn't have to do this since it wasnt intended for aftermarket connections and normally is a closed system. So while I cannot guarantee that simply splicing off the existing cable will work without any significant change to the signals, it should given how standard said paradigm is. I think thats why shops are hesitate to have people do it, because they can't guarantee how the stock HU of any random car is designed and how its signals are implemented. As long as you're OK splicing in and simply taping the wire back up if you run into issues, I say go for it if you want to be absolutely perfect. At the same time though, the signal needed to drive a sub doesn't need to be 100% pristine since its only for ~120Hz and below, so tiny imperfections will go totally unnoticed. Therefore, if you want to play it absolutely safe, taping into the front or rear door speakers post-bose amp and using the hi-level inputs on your amps would probably sound perfectly fine. I think either way should really do the trick, and would only push for going off the headunit instead of post-BOSE amp if you were adding/changing more than just a sub.

[@oblivioncth]

@@ethancontreras3538 If you do tap the high-level signals post-BOSE amp the high-level inputs on your kicker should work just fine. As for the connections, basically no custom harnesses exist for the modern Mazdas. There is the harness included with the PAC AOEM-MAZ2 for much older ones that I remember seeing someone said they used successfully somewhere, but there were some caveats and tradeoffs with it so I probably wouldnt bother.

[@grahamcaseylifts]

where did you get your steering wheel?

[@oblivioncth]

It's a KENSTYLE wheel I imported from Japan, I think through Japanparts.com (sorry I don't have the order email anymore); however, they don't seem to have the one I got anymore. I think it's the MB01 they have here www.nengun.com/kenstyle/steering-wheel-mazda-atenza-sedan-wagon-gj I dont remember exactly have to convert the Japanese car model to what we have, as they released them at different times so the ranges don't line up exact. I know the 2016 is a GJ, but forget what the sub numbers mean. In Japan some GJs are from lager years so the exact one matters. The site I bought mine on filtered by VIN and that's how I knew I got the right one. Definitely requires some research to make sure you don't get screwed, but that's definitely the manufacturer and general category for the wheel.

[@ianlewis8211]

Is this still valid on a 2019 with the Bose system?

[@oblivioncth]

I can't be 100% sure since I don't have one, but I believe so. I found the audio system diagrams for the 2018 here (warning the sites kind of crappy): cardiagn.com/2018-mazda-6-2-0l-2-5l-ewd-audio-system/ I would imagine it should be largely the same as the 2019 since no major entertainment system changes were made between those years. From looking at it, I can confirm that the line-level audio channel connections are identical and that the colors for those wires haven't changed either (0920-515A in my guide, 0920-322A on the 2018 manual). When it comes to all of the other connections to the BOSE amp, I only gave them a cursory glance but they seem to all be the same as well; however, do note that a lot of the wire coloring changed for those connections.

[@sesgust13]

Ok so forgive me for being dumb and not catching it but where do we splice the RCA

[@oblivioncth]

See the 4th to last picture in the forum post linked in the description. It's the one with the pinouts of the connectors at the BOSE amp. Connector 0920-515A, which is the widest one, is what you want. 8 of the wires/pins are for the 4-channel headunit output, ignore the other two that are for the audiopilot mic. You should be able to splice anywhere along that cable as long as you grab the 8 correct wires and know which is which.

[@Apizur]

This is a long shot, but do you have a guide to interfacing with non differential/non inverting amps?

[@oblivioncth]

Unfortunately it can be a bit tricky. Many amps can handle them fine depending on their internal circuitry even if they don't explicitly mention working with them, it mainly depends on if the ground of the channels inputs are isolated and can handle a moving reference without issue or are tied to the ground of the rest of the amp/DSP. If it doesn't work directly you will need to put a differential-to-single-ended converter between the headunit and your equipment. Sadly for whatever reason that doesn't seem to be available as a commercial device, but it is a really simple circuit that you can find many references to online. Since it can be different on a case-by-case basis, honestly I'd reach out to the manufacturer of your amp/DSP (or that you plan to buy) as they will likely be able to let you know the best way to proceed. Just let them know you have access to 4-channel differential line-level audio. The issue of differential vs single ended isn't specific to this car, its a general audio concern so I'd imagine they'd be able to offer some advice. Then you can use the information in the video for everything else. Other than a possible converter needed the connections are still the same.

[@Apizur]

@@oblivioncth Oh, you're still active on this account. I have an OLD Audiobahn A4002V so I suspect compatibility issues. As much as I hate to do it, I think I'm just gonna go the LOC route since it's only to add a subwoofer.

[@oblivioncth]

@@Apizur Ah. Yea for something older it may be harder to get information and if you're just adding a sub a LOC isn't too bad. Sorry, did you try to contact me on Mazda6Club or something? Its a long story but I've been unable to be that active anywhere due to personal issues.

[@Apizur]

@@oblivioncth I saw your post originally on the forum. I tried to trace you upstream a bit... I even looked on Steam XD, just because I couldn't find a good resource on my question. I haven't done install in a while... Did you grab accessory from the ignition cluster or was your amp voltage sensing?

[@oblivioncth]

@@Apizur Ah lol. The is ACC at the BOSE amp connections actually but my personal amp is voltage sensing.

[@C0LiSii0N]

What I don't get is; There are 11 speaker in total, but only 4 channel(8 if we check the speaker list image in japanese from your post). I can imagine that the rear door & rear twiddler share a channel and the front woofer & front twiddler too, but there are still two twitter and a center mid so.. The only thing I can think of is that the center mid in the dash get the signal from somewhere else(Combined signal from both front twiddler?) and the three front speaker(Woofer, twiddler & tweeter) on each side share a channel?

[@oblivioncth]

There are 4 input channels, that doesn't mean there are 4 output channels, but yes there is no dedicated original signal for the center. I believe the BOSE amp does something like summing the front left and right input channels and then band-passing them to the typical range centers are used for to create the center output. Otherwise, it's a 3 way setup in the front and 2 way in the rear. Each front door woofer, and front dash tweeter + twittler are associated with an input channel, being split actively or passively by the BOSE amp, while the same thing is true for the rear channels and each rear door woofer and rear deck twiddler as you said. If it was something designed to watch movies in then it would be nice to have a real 5th channel, but the four channels are just duplicated stereo anyway that exist solely for the fade function, so of course the center is going to be simulated. I was kind of interested in keeping it by doing something similar when I replaced everything, but it would have been addition work, complexity, and cost for something that was really unnecessary given the better replacement equipment of everything else.

[@C0LiSii0N]

@@oblivioncth so there are 4 channel input but 8 output? If the speaker are already wired separately up to the bose amp it would simplify the install since I won't have to wire from the amp to the speakers. I'm still debating on wether I run it as 8 channel(keeping the center one as is) or only 4(or 5)(in that case using the rear deck as sub, and component system in the front)

[@oblivioncth]

@@C0LiSii0N Yea the input is four channel, and at the output there is a separate pair of connections at the amp for all 11 speakers (sort of, a few speakers share a few). I really doubt they are doing active crossovers and its actually 11 channels as that would be nuts. If I had to guess each input channel is split to each speaker group using passive crossovers internally and then the front left and front right inputs are combined and band-passed to make a simulated 5th output channel for the center, making it more-or-less a 5-channel output. It's just that the passive crossovers are also inside so at the actually output terminals of the amp it's just the connections that go directly to the speakers. For the front, the tweeter and twiddler of each pair share a connection. For the rear, annoyingly the rear deck twiddlers are wired together. You'll see this if you look at the bottom of the forum post in the description, there's a image I threw together that shows all of the connections and makes it pretty obvious. I personally went with a direct 3-way replacement for the fronts, and then put full range monitors in the rear doors, and then just kept the stock twiddlers as a form of basic rear fill. Center was simply not used. Other than the water issues the 2014-2017s are known for causing me a bit of a headache, I've been pretty happy with it. There are definitely many ways you can go.

[@oblivioncth]

Here is a direct link to the image in question: i.imgur.com/pApxn2e.png

[@C0LiSii0N]

@@oblivioncth Thanks a lot! I missed that one on the forum lol Hey, would you happend to know the spec(Aprox.) of the bose amp(output power for example)? Like, if the bose amp output enough current, I won't buy a new one for nothing haha

[@dmanstarr]

Wouldn’t only using on left or right channel to the sub amp only give the sub one side of the stereo signal? I realize most sub data is equal on each side, but in some music there would be a difference and the sub would be missing musical data on the side not used. Am I missing something or is this just a sacrifice you are willing to make?

[@oblivioncth]

Generally in most cases the frequencies that low are going to be more or less the same, but for the small cases where it isn't, and if you want to be complete as possible then yea you'd want a mono amp that has 2 input channels, then draw from the FL and FR or RL and RR

[@dmanstarr]

Thanks for the quick response! And for sharing all the helpful info. : )

[@edgarcastillon6228]

So given the current Bose delivery (not impressed with neither clarity nor volume) what would you do to upgrade if wanted to add highs and bass? Is it even worth it?

[@oblivioncth]

I'm quite satisfied with the full system replacement I have... but it also cost nearly 4000 dollars. You can definitely achieve something almost as good, especially if you do all the work yourself for half as much. The rough thing is that with how much of the rear door speakers you hear and the fact that the speakers up front are 3-way component, there isnt a very effective way to only replace a portion of the system other than just adding a subwoofer, or maybe replacing the front woofers. Because have mismatched components in a 3-way setup can be really hard to get to sound any good, especially if you're replacing the high end. Obviously I'd start with the amp, and maybe you'd be satisfied with just doing the front 3-ways (maybe you manage to just replace the mid and high drivers and get it to sound half decent through amp tuning), though like I said I was quite surprised how much of the sound in the front is dictated by the rear door full range speakers because of how close the front seats are to them. I definitely would go a bit less name brand next time around to save some money, but unfortunately upgrading the audio in this car is expensive because of how it is set up. You cant recoupe a ton off your BOSE parts though since everyone knowa they're junk, even though they sell for a ton new. I was able to get about $400 after selling everything other than the rear deck speakers.

[@benjaminkotrla943]

Thanks for this, any chance you measured the voltage output to the BOSE amp? Thanks

[@oblivioncth]

If you mean for the amps power, it's just standard 12V, but if you mean the voltage of the signal lines, it of course depends on the signal in question and what the volume is set to. I don't recall what the peak voltage was at maximum volume. I want to say 2V but im really not sure.

[@eldergoose4075]

would you mind if i connected with you on FB mess or email? I'm going to be starting my build within the next few months, active 3 way + sub, dsp, and 3 amps. Could really use some extra pointers.

[@oblivioncth]

I'd be fine giving you my email but don't exactly want it posted publically; however, youtube has really demolished messaging on KZbin so I'm not sure how I'd get it to you. I have an account on the forum linked in the description if you didn't mind making an account there you could PM me on that platform.

[@eldergoose4075]

@@oblivioncth that's what I'll end up doing

[@eldergoose4075]

Actually I don't care if I share my Facebook and email. Facebook is Kyle Gainesville and email is [e-mail] I'll just delete after I get in touch with you.

[@zane812]

@@eldergoose4075 hey might want to delete now haha 4mos later, also, how did it go!? :-)

[@eldergoose4075]

@@zane812 actually haven't gotten around to it yet. My box was finally shipped to me this past week so soon!

[@markmiller3954]

I have a 2018 Mazda3 Touring Hatchback with the MoonRoof/Bose Upgrade and just simply bought for $199 the THX ONYX Amp that connects to my phone 📱 via a 3.5 jack into the head --- Makes a Terrific Upgrade and the Musical Sounds have a great thumping and for most songs regardless of quality (MP3, Flac, etc) the volume is never above 8 or 9 and it's as loud as a Rock Concert ---- 😎