Audio Gating question

[Rick Tinker]

There are several factors going into the quality of the system you are developing for use with HomeSeer. One is gating, another is the quality of the microphone and where/how it is installed, and another is what I will call biasing.

If you want to save some money perhaps at the expense of quality (although it may not hurt the usability of the system at all) then I know of a fellow that used to use inexpensive Stick-A-Switch components to create a home-made gate and microphone switch. This worked very well for him because when a microphone was engaged, it was as if a single microphone was connected to the computer at a time instead of having them all connected through a mixer.

The microphone angle is also important - there is a white paper somewhere at iAutomate.com's website that is reprinted with permission from Shure or Crown (I forget which) that discusses why ceiling mounted microphones are not as good as wall mount. In either case, the area around the microphone on the ceiling or on the wall is as important as the microphone itself, and the room hardness will play a big role in the quality of signal that you get back to the computer.

The biasing I refer to is just the fact that most mixers are designed for music or general purpose applications, whereas some are designed specifically for human speech. e.g. The Crown SCM410 and SCM810 mixers are designed for speech and thus bias the electronics toward filtering out frequencies that human speech cannot exist at.


So yes, you can create your own gate and it may work very well for you, but understand what each component in a top-end system is providing and see if there are less expensive ways to accomplish them so you can have a quality system at a budget price.


Regards,

Rick Tinker
HomeSeer Technologies

[pkoslow]

Keep an eye on Ebay for Biamp Advantage 8-channel gates. They have logic outputs that close contacts when the mic is gates on. Pair this with the Biamp Advantage Mic mixer and your off to a good start with 8-channel capability.

I used this setup sucessfully for over two years and ahve now moved onto a more complex setup using Genter audio conferencing gear.


Biamp Advantage Manual

[zoomkat]

Depending on how easy it is to get into the device and the LEDs, connecting a 4.7k resistor and an NPN transistor to the LED can act as an open/closed switch for some other gizmo to monitor.

I read up a bit on the boards about ways to do whole house VR and everything seemed real expensive. Then I talked to someone who had an idea, and I'm wondering if this will work. Has anyone tried just using a cheap 4 channel gate, and maybe hacking it up a little and running the active led's to an ocelot or something else to determine where the audio is comming from? Seems like it would be pretty easy to do since they tend to have a light telling which channel is in use, just take the channel info from there. They're only like 30-50 on ebay for a 4 channel one, and I assume you could stack them up to increase the amount of channels if needed.