57 minutes ago, andyh41 said:

 

...... ie the constant drone .....

 

Ah.... so you've met the wife ?

10 hours ago, SoupDragon said:

My question was serious, would not active noise cancellation null out noises that you need to hear?

 

1 hour ago, andyh41 said:

 

I imagine the method is designed to target noise that is fairly continuous in duration and frequency, ie the constant drone of road or wind noise. Talking is rapidly varying in pitch, duration etc, so wouldn't be affected.

Exactly, it's not just cancel all sound. The sound has to match the profile (in terms of frequency, duration and harmonic content - and expected variations thereof) for it to be cancelled. So all other "noise" including speech and non-related squeaks, rattles, bangs, etc. remain unaffected. So you will still hears things going wrong with the car (good) and SWMBO (not so good).

What I don't understand is if noise cancellation can be so effective ( 10 to 25db cited, and I am amazed and excited by those figures) then why it is not already in widespread use in cars, especially with the availability of cheap processing? I suspect now that my reference to 'noise cancellation' systems  in Honda Civics may be similar to Canton claims and not a true system.

I remember reading a few years back that the Canadian aircraft manufacturer Bombardier had a noise cancellation system (microphones/speakers) installed in their Q400 turboprop aircraft but I cannot remember any figures regarding effectiveness or whether they continue to install it.

A recent announcement from Continental caught my attention on speaker less ICE which looked ideal for utilising the sort of the thing we are talking about.

http://www.futurecar.com/2071/Continental’s-Advanced-Car-Audio-System-Uses-No-Speakers

 

It represents an opportunity to reduce the weight of speakers and insulation in vehicles.

 

Update: found the Q400 link https://commercialaircraft.bombardier.com/en/q400/Technology.html

There is even a video demonstrating it .... but it has no sound  

Edited 10 May, 20188 yr by Gerrycan

7 hours ago, andyh41 said:

 

I imagine the method is designed to target noise that is fairly continuous in duration and frequency, ie the constant drone of road or wind noise. Talking is rapidly varying in pitch, duration etc, so wouldn't be affected.

Should be targeted at constant drone coming from the mother-in-law.

1 hour ago, Gerrycan said:

What I don't understand is if noise cancellation can be so effective ( 10 to 25db cited, and I am amazed and excited by those figures) then why it is not already in widespread use in cars, especially with the availability of cheap processing? I suspect now that my reference to 'noise cancellation' systems  in Honda Civics may be similar to Canton claims and not a true system.

I remember reading a few years back that the Canadian aircraft manufacturer Bombardier had a noise cancellation system (microphones/speakers) installed in their Q400 turboprop aircraft but I cannot remember any figures regarding effectiveness or whether they continue to install it.

A recent announcement from Continental caught my attention on speaker less ICE which looked ideal for utilising the sort of the thing we are talking about.

http://www.futurecar.com/2071/Continental’s-Advanced-Car-Audio-System-Uses-No-Speakers

 

It represents an opportunity to reduce the weight of speakers and insulation in vehicles.

 

Update: found the Q400 link https://commercialaircraft.bombardier.com/en/q400/Technology.html

There is even a video demonstrating it .... but it has no sound  

Car manufacturers count every penny/cent so if they don't think they'll get more sales from adding noise cancellation then they won't do it - this is why the team I was part of in the late 1980s/early 1990s was disbanded - we proved that noise cancellation worked on nearly 50 vehicles but that counted for nothing as it still cost more than £0.00/$0.00. Sad, but true 

 

The Bombardier system was based on a different patent portfolio than the system I worked on but was equally effective.