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Discussion Starter · #1 ·
Hi guys! Anybody tried installing some kind of active noise cancellation system? My idea is to use a mic and a phase inverting amp to "inject" just the right amount of phase inverted road noise into the signal path running to the Harman Kardon amp. This would theoretically cancel out at least some of the low frequency road noise, if setup correctly. Are there any after market systems available? I´m quite used to developing analog electronics myself, so Another approach would be to find the HK amp and insert my own "gadget" in the signal path. Haven´t had the time to even find where the amp is located, but I guess someone here knows, and if it uses any standard plugs, such as RCA for example?

:)
 

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I'm surprised the Giulia isn't already equipped with ANC. It's a pretty common feature, one I imagine will be on many FCA vehicles in the next year or two.
 

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A form of ANC (used as engine sound enhancement) is already present on the 2.0L Stelvio. It uses the center speaker in the dash. The same system will eventually come to the Giulia.
 

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A form of ANC (used as engine sound enhancement) is already present on the 2.0L Stelvio. It uses the center speaker in the dash. The same system will eventually come to the Giulia.
Aural Viagra? Yuck. Alfas aren't Mustangs. Engine sound should be natural.


ANC systems are most effective when speakers are close to occupants ears. While the headliner is an ideal location for them, there may not be sufficient space to package speakers in the Giulia's (particularly on units with sunroof).
 

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Aural Viagra? Yuck. Alfas aren't Mustangs. Engine sound should be natural.


ANC systems are most effective when speakers are close to occupants ears. While the headliner is an ideal location for them, there may not be sufficient space to package speakers in the Giulia's (particularly on units with sunroof).
I hate when manufacturers play 'fake' engine noise through the sound system...just wrong in my opinion. Open the windows and go 'au naturel'....wind buffeting and all.
 
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Aural Viagra? Yuck. Alfas aren't Mustangs. Engine sound should be natural.


ANC systems are most effective when speakers are close to occupants ears. While the headliner is an ideal location for them, there may not be sufficient space to package speakers in the Giulia's (particularly on units with sunroof).
More particularly, the speakers need to be a carefully controlled fraction of a wavelength of the sound away from the ears unless there is a microphone near the ears. It may be possible to get some better performance if the speaker can be placed directly in line with the path of the noise. Noise canceling wide band sound to multiple ears from remotely located speakers is a very difficult problem. Mid range audio has a 1/4 wavelength of around 10cm (4 inches). To further complicate things the propagation of sound inside of a car will change when objects (like people) are in the car and or move. Even so, it is within reason to expect noise cancellation up to 100Hz or so and a lot of the noise that can get through the sound dampening materials in a car is in this range. One thing that was very apparent when I tried wearing noise canceling headphones in my pick up truck is that they amplified very low frequency sounds, such as from the suspension hitting bumps and that is something that a system manufacturer for a car must deal with.

I would think putting the speaker in the headrest would work better than in the headliner. Even so, different occupant postures and ear geometries can alter the distance from the headrest to the ears by several inches.

This makes it sound like a work-in-progress at HK:
https://www.digitaltrends.com/cars/...sing-tech-behind-noise-cancelling-headphones/

Active mufflers were once supposed to be on the horizon, but never seem to have happened.

At least one carbon fiber wheel manufacturer claims that the wheels are sound absorbing, noticeably reducing road noise.

I agree that piped in engine noises are non-sense.
 

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Discussion Starter · #7 ·
I was thinking just trying to cancel out road noise and rumble, so maybe up to say 150 Hz. Are there no after market systems worth trying?
 

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The amplifier, anyway, is housed behind the trunk liner on the left side, and it has two 22-pin connectors and a 10-pin connector, all automotive connectors, supplied by Tyco Electronics/AMP.
 

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More particularly, the speakers need to be a carefully controlled fraction of a wavelength of the sound away from the ears unless there is a microphone near the ears. It may be possible to get some better performance if the speaker can be placed directly in line with the path of the noise. Noise canceling wide band sound to multiple ears from remotely located speakers is a very difficult problem. Mid range audio has a 1/4 wavelength of around 10cm (4 inches). To further complicate things the propagation of sound inside of a car will change when objects (like people) are in the car and or move. Even so, it is within reason to expect noise cancellation up to 100Hz or so and a lot of the noise that can get through the sound dampening materials in a car is in this range. One thing that was very apparent when I tried wearing noise canceling headphones in my pick up truck is that they amplified very low frequency sounds, such as from the suspension hitting bumps and that is something that a system manufacturer for a car must deal with.

I would think putting the speaker in the headrest would work better than in the headliner. Even so, different occupant postures and ear geometries can alter the distance from the headrest to the ears by several inches.

This makes it sound like a work-in-progress at HK: https://www.digitaltrends.com/cars/...sing-tech-behind-noise-cancelling-headphones/

Active mufflers were once supposed to be on the horizon, but never seem to have happened.

At least one carbon fiber wheel manufacturer claims that the wheels are sound absorbing, noticeably reducing road noise.

I agree that piped in engine noises are non-sense.
That's a three year old article. Much work has been done since then, and ANC will be featured in more and more product introductions. Its absence will eventually be more notable than its presence.

Please tell us you don't regularly drive while wearing headphones. I wonder whether low-frequency sounds were actually amplified or were simply more noticeable with higher frequencies attenuated.

I use lower volume settings when listening to music, movies, and podcasts on my noise-cancelling headphones because the source material no longer has to overcome the background.

Headrest packaging is arguably even more challenging than headliners and presents the added difficulty of wire routing when the headrests are adjustable.

Will be interesting to see how this all plays out.
 

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I was thinking just trying to cancel out road noise and rumble, so maybe up to say 150 Hz. Are there no after market systems worth trying?
The apparently quick answer is NO, because there are no after market systems available at this time.
This requires integration into the car, making it difficult to make a generic system that will work.
 

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That's a three year old article. Much work has been done since then, and ANC will be featured in more and more product introductions. Its absence will eventually be more notable than its presence.
Maybe, but how many cars currently have HK designed noise cancellation? I think Bose is ahead of HK with this tech. Also, shouldn't getting the sound quality for the regular system right be a higher priority?

Please tell us you don't regularly drive while wearing headphones. I wonder whether low-frequency sounds were actually amplified or were simply more noticeable with higher frequencies attenuated.
Why are you worried about a person wearing noise canceling headphones while driving? FWIW: DOT is living in a past century in this regard. Even though they finally admitted that commercial truck drivers can be deaf (as-of August 2014), they still require a hearing test as part of the bi-annual medical examination of all such drivers. What is the examiner supposed to write on the report "yep, still deaf"?

Anyway, I am certain that the low frequency sounds were amplified and I stopped using the headphones due to this. Which is better, sitting in front of the trumpets or in front of the bass drum? Either way your ears get pummeled. Oh yeah, the headphones nearly perfectly canceled the diesel engine noise and also managed to cancel quite a bit of wind noise.

Note that the HK article describes the need for accelerometers in the suspension in order to make the system work. I believe that this is needed to be able to cancel the thumping noise from the suspension. This noise is going to travel in the structure of the car as nearly inaudible, high velocity P waves, then be converted to highly audible S waves when the structural component sharply angles into a panel (read: a suspension thump travels straight and inaudibly up your A pillars and your A pillars then act like a drum stick banging on your roof panel). Without a stress gauge or accelerometer near the source of the thump, the noise cancellation system has no chance of counteracting this noise. Even with such gauges, the conversion of P to S waves is non-linear, making it really difficult to implement the noise canceler since the text book implementation of a noise canceler is built around an assumption of a linear system.

I use lower volume settings when listening to music, movies, and podcasts on my noise-cancelling headphones because the source material no longer has to overcome the background.

Headrest packaging is arguably even more challenging than headliners and presents the added difficulty of wire routing when the headrests are adjustable.

Will be interesting to see how this all plays out.
I didn't say that noise canceling technology is bad nor that it doesn't work, just that it is hard to make work in a car. If a good working system were offered with Giulia I would have paid money for it. However, handling, performance, "no Bosch", and "not VW/Audi/Porsche" are higher on my list than this "nice to have". Do you want a limited slip differential or a noise canceling sound system: my answer to that question should be pretty obvious by now. YMMV.

Some vehicles have screens and speakers built into the backs of the headrests in an attempt to placate those younger family members. So it is apparent that building electronics into the headrests is feasible. These video screens can be incredibly distracting when driving behind such a vehicle at night.

http://www.ebay.com/itm/like/152477789879?chn=ps&dispItem=1
 

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A form of ANC (used as engine sound enhancement) is already present on the 2.0L Stelvio. It uses the center speaker in the dash. The same system will eventually come to the Giulia.
Any way to tell if your Giulia has it? I ordered mine just over a month ago - expect it to be delivered sometime in March 2018.

I see that the online car configuration tool (in the Netherlands) lists Engine Noise Enhancement as a 'standard' now, but can't remember if this option was present when I ordered it towards the last week of Dec 2017. And my build sheet doesn't list any standard options.

Thanks!

-krish
 

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ANC typically uses separate microphones from those used for hands-free phone. If you find a separate pair in the headliner that would constitute a strong clue.
 

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Any way to tell if your Giulia has it? I ordered mine just over a month ago - expect it to be delivered sometime in March 2018.

I see that the online car configuration tool (in the Netherlands) lists Engine Noise Enhancement as a 'standard' now, but can't remember if this option was present when I ordered it towards the last week of Dec 2017. And my build sheet doesn't list any standard options.

Thanks!

-krish
My Sept 2017 Giulia 2.0T USA spec build does not have it. What to look for is described by MacGeek in this hard to find thread:
http://www.giuliaforums.com/forum/2...neral-discussion/19577-d-n-observation-3.html

There should be a relatively obvious, fairly large round-ish plastic thing (70mm or so?) next to the intake duct in the gap between the engine cover and the duct. My car just has a large gap, which is fine with me.
 

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My Girlfried has a 2016 Buick Encore (mini SUV) that has ANC... It also has Apple CarPlay..all for21000. Just saying
 
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