2014~2021 Audio Upgrade Log - Mazda6 Wagon 2019

Mazda 6 Wagon 2019

Greetings from Jakarta, Indonesia!

I want to share my audio build log for my Mazda 6 Wagon/Estate 2019. This model comes with Bose sound system, 11 speakers (1 dash center, 2 dash midrange, 2 door-pillar tweeters, 2 8'inch woofers in the doors, 2 rear door speakers, and 2 side speakers in the back. I also post this in other relevant forums.


I think the Mazda 6 Bose system is pretty good and I believe it will satisfy most people - in fact, it runs a three-way system which can cover wide frequency adequately. However, I want better sound quality. I consider myself as audio enthusiast, but not fanatics. Also too lazy to tinker around sound tuning. At home I have Scanspeaks speakers driven by Rega amplifier & Cambridge Audio streamer, and in my other car, I run a set of Morel speakers driven by Genesis amps+ processor. So I have an idea what kind of sounds I'd expect from my (daily) car.

I am not chasing a "perfect" sound in the car. In my opinion, it is virtually impossible to achieve a "home-like sound" in a daily drive car, because a) the inherent acoustic characteristics; b) road noise; c) driving experience and safety; and d) compromise of space. I've heard contest-winning cars - they sound great during stationary, but they are terrible cars for driving. This is why I avoid permanent mods to car interior and strive to save space as possible. Speaker placement in stock location is indispensable for me, because I don't want driving with huge speaker pods in front of my face. As I often bring my family along, space is important and also their listening pleasure as well. In summary, these are what I want to achieve through this install:

- SQ sound, tendency for top 40 music, pop, rock & heavy metal. Probably less than 5% listening to EDM or those with big bass sound.
- Stock speaker placement, no interior mods
- Space efficient, and run efficiently (not excessively taxing car electric system)
- Not more than 1 week to install and tuning
- Good for all-seat experience, but when I drive by myself, I can switch to driver-oriented sound.

Based on above, I draw the plan and asked my installer to do as I wished:

Sound Deadening
Sound deadening in all doors, to minimize rattle and create solid "housing" for door speakers. I also put foam around door speakers. Mazda 6 is a reasonably silent car, so no need to put more deadening on floor, roof, or engine. Solid doors will help to deliver solid midbass performance.

Processor & Head Unit (Signal Tapping)
Since all-seat experience is one of objectives, then I have to use a center speaker. There is only Alpine H800 still in the market which can faithfully process center signal with its Dolby processing. However I have spare MS-8 and decided to use it instead. I think the Logic 7 in MS-8 is better than Dolby in H800 for center processing. Moreover, its autotune feature is unbeatable and no processor in the market can do that as good as MS-8. For lazy ass like me, this is relieving. It's been discontinued and I've owned it since 2012, but it's still in good condition. Till date, I am still wondering how many years they can survive. With all of its pros & cons, and quirkiness, I still think it is a great product and no equal replacement in the market (when it comes to auto tune and center processing).

I read that Helix DSP Ultra and DSP.3 has center processing capability (they call it "Real Center") but looking at the documentation, I am not sure it is processing center channel like the way Logic 7 or Dolby do. It seemed that it is an enhanced sum L+R algorithm and it is marketed for front listening experience (driver+passenger) instead of all-seat experience. My reference installers are also not familiar with this feature, perhaps because it's quite new here, so I can't find reliable hands-on reference. Probably I'll replace the MS-8 with this in the future, if I have time to tinker around sound tuning. For sure, the Helix DSPs are the best in the market today.

No plan to change head-unit. I need the features and no mods on the dashboard. In fact, I believe the Mazda 6 HU is damn good. I realized this when I searched audio upgrade topic in Mazda 6 Forum. This is a very good thread in this forum: . it is now a sticky post. Kudos to the poster. I also attest that this article is valid for Mazda 6 wagon 2019 - that no feature lost by tapping the pre-BOSE amp and you can safely remove the BOSE amp.

The standard HU output is low-level, no equalization, in-phase, balanced, and differential signaling. This makes integration to sound processor is easier than I initially thought and the processor will be fed with high-quality signals from HU. I just tap the Front Left (FL) and Front Right (FR) signal (Black+White and Red+Green), add it to two RCAs connectors (FR and FL) and connect it to low-level input of MS-8, and presumably other processors (Channel 1 & 2 only). That's all!


Speaker Selection & Placements
For fronts, I use Audison APK 165 2ohm, active. It's a two-way component set. I put the tweeters on stock door pillar, and woofer on the stock door location. Tweeter must be 1" for stock location. I use the supplied passive xover for tweeter but go active for the woofer. The xover will be able to "soften" the tweeter sound (new tweeters usually sound harsh before break-in) and also protect it from potential surge of low frequency. The woofer is 2ohm, meaning it will get more juice from the amplifier. I believe that for solid midbass performance, the woofer should be fed with power headroom, say around 30-50% more so that in the event of higher excursion needed, the midbass can deliver their job. In challenging stock location, this power headroom is crucial because it helps the woofer to sound louder and easier to EQ. Audison APK Woofer asks 70W RMS, and I supplied it with amp 130W @2ohm.


For center, I use Morel Hybrid Integra 402. The stock center location actually can only handle 3 or 3.5" speaker, so I had to make slight cutting in the stock placement, but just minor cut and I can easily return the original center BOSE speaker in the future. This Morel is simply amazing and they can handle low frequency up to 80Hz. For center processing, the center speaker has to be good quality, or even better than front speakers. This is because center speaker has to be able to play low frequency (say 100-300Hz) up to 20KHz for strong center image/staging. This is more important for licensed processing like Logic 7 or Dolby. Any good 3-4" driver can do this, as long as they can faithfully deliver 200Hz-20KHz, but I have bias over Morel, so this is very subjective. I place the crossover under the driver seat.

I also think that coaxial won't work in center because of height of tweeter. Point-source will do.


The stock location can cater separate tweeter + 4" midbass for better performance. But to make life simpler, I opted for point-source driver instead. Point-source drivers are easier to EQ due to phase coherence, instead of coaxial. This is important for front application. Other than Morel Hybrid, there are Morel Tempo Integra and Audison APX 4 which employ concentric tweeter.

For rear door speaker, I use JBL GTO629. These are very efficient speaker, at 3 ohm. They're not crucial for front side listening, but for rear passengers in all-seat listening, they can make difference. They're more for ambience purpose.

For subwoofer, I used powered subwoofer Rockford P300-10. It is in sealed enclosure, with tendency for tight bass. I listen more to SQ, and I don't really like boomy bass. I need space in my boot, so this active subwoofer package is the answer. It's easy to install, practical, and importantly, its built right and the box size is proper. I didn't want to build custom enclosure in the trunk because it's difficult to size it right. Subwoofer has to be placed in right enclosure size.


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Mazda 6 Wagon 2019
Amplifiers and Cables

For front speakers, I use Audison AP4D 4x70W @4ohm. Each channel goes to 2 tweeters and 2 woofer. Woofers are 2Ohm, so they get 130W instead. More juice is good for midbass. AP4D doesn't use gain control, and its gains are controlled by processor. This is important for MS-8 because tuning will require "matching" level. I don't want to spend back-and-forth playing the gain control in amplifiers when tuning with MS-8. AP4D is small and runs cool.

For center and rears, I use DLS Reference CC-44 4x85Watt. Center is bridged, to Center get 220Watt (Morel can handle it, and it is needed to play low frequency), and the remaining 2x85watt goes to rear speakers. DLS is AB class whilst AP4D is D class. AB class, on paper, can deliver more detailed frequencies than D class (DLS Reference claims 10Hz-60KHz vs AP4D claim of 20Hz-22KHz). However DLS run hot and it is more sensitive to voltage fluctuation in car. I need steady power and cool amp, so I opted for AP4D to power my front speakers because they will work hard. DLS is for center and rears which are not heavy and theoretically, DLS can deliver richer frequencies for center speaker which is the most important speaker for surround set-up. I actually prefer to use a set of same-brand amplifiers, but this DLS was my spare amp and I didn't want to spend more money on amp.

I've been using AB class amp, G class (Genesis amp - they're superb!), D class in car environment. I think the sound difference is hardly noticeable and I am not that detailed anyway. Footprint and actual power output are the most important things for modern car amplifiers.

Since I am using active subwoofer, I can save space for monoblock.

Amps and processor are placed in the trunk, before the spare tire. I only need to place custom MDF box there to put the gears. I can easily put back the stock Styrofoam box there in the future if I want to return to original parts. It also saves my trunk space and hiding the all the gears from plain sight.

Cables. Choosing speaker cables are easy - as long as they have plenty/bulk strands, they're good. I don't buy into brands when it comes to speaker cables. RCA is a bit tricky because it is difficult to see strands and the fact that RCA heads really matter. Mazda 6 original cables are thin, and they're not actually suited to deliver high power. It is easy to replace center speaker cables, but door speakers are difficult because the space for lay new cables to doors are practically not available. My installer could lay new cables to woofer, but not to tweeter, so I had to use standard cables to tweeters.


Tuning and Sound Quality

After several calibration attempts, I finally settled for following cross-over in MS-8
Center 1-way: 200Hz
Sub: 30Hz and 80Hz
Front 2-Way: 3500 Hz
Rear 1-way: 200Hz

I run all 8 channels. These numbers may change as the gears will break-in over time and it will require re-tuning. Albeit the Center can play down to 80Hz, after several tuning attempts I realized that it won't work in this setup. A single center speaker probably not strong enough to do the heavy-lifting. Under Logic 7 (MS-8), the MS-8 will attempt to channel the unplayable center frequencies to door midbass, so it'd better to rely on Morel center speaker to play 200Hz to 20KHz, and share the burden of 80Hz-200Hz to the midbass.

There are tons of MS-8 tips and tricks in diymobileaudio forum. It's a good place to start understand MS-8. One of key quirkiness of MS-8 is to setup with slightly audible level of speakers/amps. I just need to slightly open the gain for DLS and Subwoofer, and thankfully no need to set gain for AP4D. I set the MS-8 calibration volume at -40 and made sure the sub was barely audible. After calibration, I slightly increased the sub gain.

After 4-5 calibrations, the final calibration outcome is fantastic and consistent. The image is dead-center, staging is wide, superb clarity, and dynamics are there. Midbass is rich. All-seat sound is fantastic as well for rear passengers. More importantly, I only use small space in my trunk for the subwoofer and remaining speakers are in stock location. HU is retained and all features stay (except BOSE centerpoint). Since I use apple car play + Onkyo HF player, I can throw high-res audio (96/192Khz Flac, DSD) into my system and they sound even better!

Tuning only takes probably about 1-2 hours, and all installations takes about 4 days. WIth OEM looks setup and fantastic sound, driving this lovely Mazda is really enjoyable.

The gears I used are not top of the line of their respective brands. However they are really suited for car environment and highly efficient. This is important for car environment and this allows stealthy setup (OEM look). The sound quality is fantastic. Of course there are higher-end models to improve the sound, ie. Audison Thesis, Morel Supremo/Elate, JL HD amps, etc. However they will require interior mods to make them really shine, and with the law of diminishing return in audio, I may need to pay 2-3 folds higher but the sound improvement will be hardly twice better. Let alone time required to install and tuning them.

Processor is similarly important. It's like a conductor which coordinate all the gears to work flawlessly. Proper install and great tuning (processor) can bring the best of the installed gears.MS-8 is great and suit my needs very well, albeit it is an "archaic" product.

In the next few days I will try to upload more photos and audio/video recording (recorded using iPhone Xs)
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Mazda 6 Wagon 2019
After driving this for more than a month, I decided to make minor changes to suit my liking.

Now I run my two way speakers with DLS amp - it powers the sail tweeters and door midbass. I removed that tweeter crossover, so they are fully active. Tweeters get 85W and Midbass get 130W as they‘re 2ohm.

The Audison AP4D powers the center speaker(bridging to 220W) and rear door speakers (70w each).

I also changed the crossover setting to be as follows:
Front two way: 3500Hz
Center: 300Hz
Rear: 300Hz
Sub: 80Hz and 35Hz

without the crossover, I think the Audison AP1 tweeter work best and they blend very well with the AP6.5 midbass.Tweeters now can go down to 3500Hz without crossover, where the AP6.5 would be struggling to cover.

the sound is nicer and warmer (these are highly subjective words). I’m not sure whether it is due to more headroom from higher power or because the AB DLS amp sound nicer than class D Audison.

center is now limited to 300Hz. I realized that the morel 402 will always be struggling to achieve lower than 300Hz because of IB/drop-in placement. It is supposed to use closed baffle or perhaps aperiodic to maximize lower frequency. Perhaps it is for future change. By using 300Hz for center speaker, the MS8 will steer anything below 300Hz to door speakers which work flawlessly in these frequencies.

I also did minor changes in the EQ though MS8 to meet my liking - I generally cut some high frequencies (above 2K freq) to achieve „muted“ sound like analog or vinyl.

to reduce rear cabin noise, I put some sound deadening in the rear cabin, and it works very well. Rear cabin noise is a common problem for wagons due its design.It was exacerbated low profile tires & rims, and bad road quality in Jakarta.

in overall, I am happier with this setup. I did quick RTA and FFT test using my iphone standard/internal mic. I think this setup will stay for long.
Mazda 6 Wagon 2019
I just uploaded some sample songs into Youtube. Not sure if it works in your countr(ies) due to copyright but here you go.

Recorded with IPhone Xs. Each song is around 1 minute only and low quality resolution to prevent copyright issue in youtube.

Love of My Life by Queen
Second Hand News by Fletwood Mac
Killing Me Softly by Dee Dee
Don't Start Now by Dua Lipa
One Evening by Feist
Mazda 6 Wagon 2019
Short update...

After 8-9 months, I decided to deploy Helix DSP3 and run all Morel Hybrid speakers (front, center, rear) and Rockford P300 active sub. Morels are powered by DLS reference and Genesis profile.

It's been a significant upgrade and it sounds amazing. The speakers are substantially better and the DSP3 is a new toy to play around, especially during this pandemic situation.

Tuning however is not as easy as MS8 (as expected). It turns out that the Real Center implementation in Helix is not as good (or easy) as the L7 in MS8. Setting up rear speakers is also more challenging. After toying around with DSP3, I appreciate what Andy W and team did and I really think that MS8 is really a masterpiece. It's too bad that it's been discontinued. If JBL (or anybody else) eventually decided to upgrade MS8 with modern circuitry and keeping the L7 implementation, I'd definitely jump to it. Nonetheless, DSP3 is really a gem and a solid piece of equipment. It's equipped with modern circuitry to cater modern automobiles, and the software is great.

One more thing I notice on the difference between MS8 and DSP3 is on the sound signature. This is of course highly subjective and not scientific. I feel that MS8 offer "warmer" sound signature, and DSP3 is "colder" but with better clarity/detail. Install probably could play role here, or perhaps because they're on different DAC. Not sure. Nevertheless, these two are great DSPs and I don't regret to switch to DSP3
Ottawa, Ontario
17 Mazda 6 GT
Man o man, if there was a 6 wagon available here in Canada, I'd get one in a heartbeat.
Wagons aren't a good sell here though, so I guess that will never happen. Sigh..

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