[Nola111]

I just wanted to throw this out there as a reference in hopes of helping some folks. I've extensively tested 3 PC BT solutions now, and I just wanted to share some of my experiences.

Here are the 3 main issues that people (including me) have run into when using any PC-based BT handsfree solution, and current known solutions.

1. Noise - by this I mean that the person on the other end of the call complains of the background noise of the car and the road is so loud that it's hard to hear or understand the person in the car talking. There are several noise-canceling mics that you can buy that will help remedy this. They will greatly reduce the road and background noise going into the mic, and make the person on the other end of the line less likely to hang up on you. This is the easiest issue to remedy of the three.

2. Echo - echo can affect both parties on the call, or just one. The main complaint you'll hear is again from the person on the other end of the call, who says they can hear themselves echoing back through the line after they've spoken. This is caused by the microphone you're using picking up the sound from the speakers. One of the solutions for this is a half-duplex approach, which can be present in either hardware or software. In simplest ways of putting it, the microphone mutes itself when you're not talking into it. This prevents the speaker output from entering the microphone. The shortcoming of this is that half-duplex is basically what you're doing when talking on walkie-talkies. It can be frustrating at times when being used to full-duplex conversations on a telephone. Some USB mics used mainly for business teleconferencing have built-in echo cancellation, but as soon as you introduce a USB mic into the mix, you face issue #3...

3. Audio latency (delay) - There is a delay, anywhere from a second to 3 or 4, between when you talk and when the other person actually hears you, and vice-versa when they talk to you. This is by far the most annoying issue to deal with when trying to hold a conversation. My wife refused to talk to me on my former handsfree system until I remedied this. The latency is caused by Windows' simultaneous handling of two soundcards. I mentioned the USB mic above... as soon as you introduce a USB mic to the mix, you're introducing a new soundcard. In this case, you have to use the USB mic as your recording soundcard, and your normal soundcard for your speakers as your playback soundcard. Using the same sound card for your speakers and your mic is one way to reduce latency to almost nothing... the bad news is though that most noise-canceling and echo-canceling mics are USB mics. They have to be since they require more power to perform their functions than the very small amount of power that regular 1/8" or 1/4" analog mic jacks put out. So this causes a bit of a conundrum... How do we solve 1 and 2 w/o creating 3? Most OEM BT solutions coming out in cars these days handle 1,2, and 3 by having all the hardware and firmware as one integrated system (not to mention that the system doesn't have to process other PC activities!). The mics they install in the cars have noise-canceling and echo-canceling technology built-in (with plenty of power to draw from the audio system), and the latency is not present because it's all tied in to the same audio system (as though on the same "soundcard" so to speak).

There is a hardware solution out there that works to reduce all three issues. It's called the Phoenix Audio SOHO. A couple associates of mine report great success with it. The only downside is that it requires a PCI slot, which a lot of car pc users don't have.

So that's that. Hope it helps people understand as they run into these issues. I'm raising my happy hour glass now... here's to David, Scott, et al finally cracking the code in Windows to be able to kill all three of those nasty issues above for us Centrafuse lovers, regardless of our systems and hardware. The "other pc solution" of which I was a private beta tester was not able to accomplish it before they went completely south and gave up. I have a feeling that our boys will be able to do it.