It's funny to see a technique being heralded as 'novel' which has been use for well, I personally have known it for at least 20 years. In earlier days it simply consisted of connecting two dynamic mikes anti-polar (connect the "minus" terminals together, and take the output from both "plus" terminals). The idea is that noise from a distance will arrive at the same time at two mikes next to eachother, thus cancelling out signal in that configuration. Noise from proximity (i.e. your mouth) would induce a difference in pressure and would thus create a signal.
You can still see it used when technicians have to quickly rig mics without the benefit of a sound check or equaliser - just check for mike pairs.
The difference is now that such balancing has to be done by electronics (opamps) because electret microphones cannot be set up in that configuration - until someone gets smart and sticks it in one house..
The only place the word 'new' appears in the article is in the sentence "This multi-mic idea is not new" - so you are correct in your comment when you state "New? Not by a long shot". Perhaps a second reading of the article is in order before you post comment upon't?
"This multi-mic idea is not new, but it requires memory and a fair chunk of compute power to process the audio streams. Dynamic Hearing said it chose CSR because CSR's BlueCore5-Multimedia chip has both memory and a DSP (digital signal processor) built-in."
This is the quote in the article. Granted the technique isn't new, however, the fact that you're doing it in a bluetooth headset is a novel idea.
The common way to use two microphones is just to wire them together. So why are they using a signal processor? Are they using a delay loop so they can try mounting the two microphones further apart?
The more interesting thing that you can do with two microphones and a signal processor is, you can cancel noise at the earphone, to make it easier to hear the conversation. People know about that, but no one ever actually does it.
The most interesting thing you can do is predictive noise cancelation of cyclic signals - like car engine and road noise. If they are trying that, I wish someone would say so.
Check out the Jawbone bluetooth headset, it has 3 mics and noise cancellation and has been on sale since last year. I bought one and it works as advertised.
Ummm... not even novel in a bluetooth headset... #
Posted Monday 11th June 2007 08:39 GMT
It's not new tech (as noted) but its not even novel in a bluetooth headset. I own a Jawbone Bluetooth (http://www.jawbone.com/) and it does the same thing...
Even if there's nothing new, chances are, they'll probably manage to get a patent for it in the USA where the patent office almost seems to specialise in granting patents for what the rest of the world very rightly accepts as unpatentable.
Bluetooth headsets to get dual mics
Peter
This is not a new technique at all #
Posted Sunday 10th June 2007 17:19 GMT
It's funny to see a technique being heralded as 'novel' which has been use for well, I personally have known it for at least 20 years. In earlier days it simply consisted of connecting two dynamic mikes anti-polar (connect the "minus" terminals together, and take the output from both "plus" terminals). The idea is that noise from a distance will arrive at the same time at two mikes next to eachother, thus cancelling out signal in that configuration. Noise from proximity (i.e. your mouth) would induce a difference in pressure and would thus create a signal.
You can still see it used when technicians have to quickly rig mics without the benefit of a sound check or equaliser - just check for mike pairs.
The difference is now that such balancing has to be done by electronics (opamps) because electret microphones cannot be set up in that configuration - until someone gets smart and sticks it in one house..
New? Not by a long shot..
Pat Reynolds
Re: This is not a new technique at all #
Posted Monday 11th June 2007 02:59 GMT
The only place the word 'new' appears in the article is in the sentence "This multi-mic idea is not new" - so you are correct in your comment when you state "New? Not by a long shot". Perhaps a second reading of the article is in order before you post comment upon't?
Malcolm Weir
Yes, Peter, we know #
Posted Monday 11th June 2007 03:03 GMT
We know the concept isn't new. The article explicitly says that it isn't new. And I'm not seeing the word "novel" used either.
This is about a development: putting the concept to work in a Bluetooth headset.
Ian Michael Gumby
Reading is Fundemental #
Posted Monday 11th June 2007 03:03 GMT
"This multi-mic idea is not new, but it requires memory and a fair chunk of compute power to process the audio streams. Dynamic Hearing said it chose CSR because CSR's BlueCore5-Multimedia chip has both memory and a DSP (digital signal processor) built-in."
This is the quote in the article. Granted the technique isn't new, however, the fact that you're doing it in a bluetooth headset is a novel idea.
Anonymous Coward
Just additive cancilation? #
Posted Monday 11th June 2007 03:03 GMT
The common way to use two microphones is just to wire them together. So why are they using a signal processor? Are they using a delay loop so they can try mounting the two microphones further apart?
The more interesting thing that you can do with two microphones and a signal processor is, you can cancel noise at the earphone, to make it easier to hear the conversation. People know about that, but no one ever actually does it.
The most interesting thing you can do is predictive noise cancelation of cyclic signals - like car engine and road noise. If they are trying that, I wish someone would say so.
Anonymous Coward
Been there done that bought the Jawbone... #
Posted Monday 11th June 2007 08:39 GMT
Check out the Jawbone bluetooth headset, it has 3 mics and noise cancellation and has been on sale since last year. I bought one and it works as advertised.
Martin Eriksson
Ummm... not even novel in a bluetooth headset... #
Posted Monday 11th June 2007 08:39 GMT
It's not new tech (as noted) but its not even novel in a bluetooth headset. I own a Jawbone Bluetooth (http://www.jawbone.com/) and it does the same thing...
Anonymous Coward
Reinventing the wheel #
Posted Monday 11th June 2007 11:29 GMT
Even if there's nothing new, chances are, they'll probably manage to get a patent for it in the USA where the patent office almost seems to specialise in granting patents for what the rest of the world very rightly accepts as unpatentable.