Announcement

Collapse
No announcement yet.

Example of echo cancellation with whole house audio and open air mics

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Example of echo cancellation with whole house audio and open air mics

    I've received a number of emails asking about my VR setup since posting the HS User Profile. Spent a little time today making some recordings that along with this description, will hopefully demonstrate the system.

    Audio Description: I'm using Russound A-Bus keypads to power in-wall speakers in most rooms of the house, with 70v Bose speakers delivering mono sound to the garage, laundy room and outside areas. Sources (Audiotron, CD Changer, Radio, TV) are fed into the inputs of a Biamp SPM723 preamp. The three outputs are distributed to 1-House, 2-Garage & Laundry, 3-Outside areas.

    The house & garage/laundry can listen to any of the available sources and the outside areas can play what's playing in one of the previous zones. The biamp SPM723 provides what's basically a 7-source (I'm only using 4), 2/3-zone distributed audio system. The SPM723 also has 2 mic level inputs... the TTS output of the HS server is connected to one, and the ouTput of a phone interface (Gentner AP10) is connected to the other. The neat benefit of this is that when TTS speaks, the background music is automatically reduced to a low volume and then slowly ramps back up to the previous volume once the TTS announcement is complete. If the phone interface is used which created a whole-house "speaker phone", the SPM723 is programmed to cut the background music all the way off until the phone call is complete.

    The Biamp SPM723 is controlled via RS-232 and is very configurable... TTS announcements can be selected to play in any of the 3 zones in any combination (normally TTS does not play outside).

    VR Description: Crown MB3 mics are installed in the walls of most rooms plus the garage and laundry and connect back to a Gentner AP800 mic mixer which is designed for teleconference use. This is a very capable mixer that is controlled via RS-232 and provides sophisticated mic gating, noise filters, EQ, and echo cancellation as well as a matrix mixer.

    The mics are connected to the mic inputs and the output of the whole-house audio system as well as the television are connected to two of the inputs. One output of the mixer is connected to the line in on the sound card of the HS server for VR. The AP800 also has logic outputs that register which microphone is gated "on". These outputs are conncted to the inputs on an Applied Digital SECU16i which in turn can let HS know which mic is on, or more importantly... which room you are speaking from!

    Back to the whole-house & television audio that are connected to the inputs. With these connected to the AP800, echo cancellation can be configured that effectivly removes these sources from reaching the sound card input. This helps greatly with two things:
    1. Reduces the amount of sound that reaches VR by cancelling the TV or background music... only your voice is heard!
    2. Eliminates VR from hearing the TTS announcements back in the mics.
    The benefits of number 1 are obvious... VR is much more relaible and can be used while listening to music or watching TV. Number 2 isn't as obvious, or at least wasn't to me at first... here's why. I don't switch TTS announcement to specific rooms in the house (only between the three zones mentioned above), so when TTS talks, it talks in every room of the house. This created the following problem:

    Now that HS knows which room you are speaking from, VR commands can be simplified. Example: What used to be "Bedroom fan on", can now be "fan on", etc. But, during conversation with VR & TTS (again, with speakers & mics in most rooms), the TTS announcements would gate on another mic, most likely not in the room where you are and confuse the system sometime making it think you are in a different room.

    Having the echo cancellation feature of the AP800 remove TTS from the VR input solves this problem nicely.

    Results: OK, enough jabbering... show me!

    I made a couple recording that demonstrate some of what's stated above. The recordings were taken from my HS server's line in, which is exactly what VR "hears".

    The first recording is with echo cancellation turned off. You'll notice that you can easily hear the backgroud music as well as the TTS announcements. Remember that once HS picks up my attention phrase and speaks the confirmation "Yes Paul", the background music will be lowered during the conversation by the SPM723 preamp and then ramps back up at the end once TTS completes (this is not echo cancellation at work).

    Click here to listen to an MP3 with Echo Cancellation OFF


    The second recording is with echo cancellation turned on and attempting to remove much of the background music and TTS. You'll see that it reduces the music by at least half, and the TTS announcements are almost completely gone!

    CLick here to listen to an MP3 with Echo Cancellation ON

    I wasn't able to attach the recordings to the post, so hoping that the links above will take you to .mps's that are on my server. TTS responses seem a little slower than normal, probably becasue of the recording app sucking CPU on my lowly 1Ghz server.

    My next task is too connect a weatherproof microphone outside which can be used as an intercom from the front gate, to record outside audio when the alarm is triggered and also to cancel outside noise from the inside mics. I live in a mild climate so the house doesn't have any insulation and doors/windows are often open. With this in mind, noises from outside like large trucks, barking dogs, etc are picked up by the inside mics and can interfere with VR (don't know why, but seems like in the middle of a VR command, the neighbors dog will always bark!)

    Cheers,
    Paul
    Last edited by pkoslow; November 7, 2009, 07:22 PM.

    Click to visit: www.sbsmarthomes.com
    Santa Barbara Smarthomes

    Authorized Russound Dealer & Installer

    Personal HA Website

    HomeSeer User Profile

    #2
    Hello Paul,

    This is very nice info and very useful. Your setup totally blew me away. Thanks. I have gone thru all of your posts and still not clear about the speaker switching with the whole house audio being on the A-bus based keypads.

    I am planing to install the russound A-Bus A-H484 (4-source, 4-zone, 8 room). How do I acheive speaker switching. Can you please put some light on it.

    I noticed that you personally recomment Russound CAV6.6 but as I am low on budget A-Bus may be the only way to go for me.

    Thanks,
    Shaurya

    Comment


      #3
      Very cool! I'm going to make a request, but don't worry about if it is a pain as I'll figure it out ;-)

      As someone new, I'm still having to run around to tons of sites and figure out where to find stuff. Would it be possible to get a spreadsheet of each component you use in your whole house audio/VR setup, its purpose, and most importantly where I can get one? ;-)

      Again, if this is info you'll have to run around to collect don't worry as I'm sure I'll find them ;-)

      Comment


        #4
        Shaurya,

        I'm not doing speaker switching in the way you are inquiring about. I can direct TTS announcements in any combination to the following three zones:
        1. Main House
        2. Garage & Laundry Room
        3. Outside areas
        The Main house is where I'm using A-Bus, and it's the older 1-source equipment. TTS announcements are played throughout the entire house and not switched to only the room where the VR commnad originated like you're hoping to do.

        I think this is doable, but not a feature I was interested in. That said, I think this will be very difficult to do using the A-bus technology. As you mentioned, the speakers are connnected to the keypads and not centrally so using any type of speaker switching device like the AB8SS will be difficult to wire... if you also want to use the A-Bus for background music this will add some more complexity (how do you select sources on the newer A-Bus gear... is it with the IR remote?).

        To do what you want, I think the CAV6.6 would be a much better fit as HomeSeer can control it with RS-232 and with enought scripting you can probably get where you want with directing TTS to individual or combinations of rooms.

        ***My advice to any of you jumping into this is to take it step by step... setting up reliable VR can be very frustrating and takes lots of trial and error to get it right.

        First get you mics and mixer installed and work on getting good VR results in your house. This will require level adjustments, tweaking gating parameters, EQ & filter settings, and don't forget that mic placement can be critical as well.

        After you get VR working well... move onto connecting the gate outputs form the mixer to HomeSeer so it knows where you are. This again will take some experimentation and scripting to get working well.

        From here, move to directing your TTS output to the room that you are speaking from. I've not done this, so please share your results/experience if you get there.

        If you haven't already... search the archives for posts from "pkoslow" that include "Gentner, Biamp, VR" and you should turn up a number of other posts with detailed information about VR tuning.

        Heres one with some good info:
        http://board.homeseer.com/showthread...hlight=gentner

        Cheers,
        Paul

        Click to visit: www.sbsmarthomes.com
        Santa Barbara Smarthomes

        Authorized Russound Dealer & Installer

        Personal HA Website

        HomeSeer User Profile

        Comment


          #5
          CIC,

          You may have already seen it in a previous post, but I'm attaching a picture of the rack that has some information to the side of it. I've purchased most everything in the rack used to keep it affordable... much of it came from Ebay, so there's a good place to start.

          This stuff is really expensive new (just the 3 Gentner devices would be >$11,000 Retail), but the same setup can be found on Ebay for $500-800.

          Before trying to find out where to buy it all, I'd suggest researching the equipment and reading the manuals to get a feel of what it can do so you're sure it's a good fit with what you want to do.

          Here's a few links to get you started:

          Gentner AP800 Manual, Docs & FAQs

          Gentner AP10 Phone Interface Manual, Docs & FAQs

          Biamp SPM723 Manual, Data Sheet, RS-232 Control

          Crown PZM-11 Mic, Crown MB3 Mic

          Useful information from Crown about using boundary mics

          Bogen Pro Matrix Specs, Manual, Brochure

          If any of you start down this path I'll be happy to share scripts and Gentner AP settings, but realize that settings for your VR especially around how the mixer is adjusted/configured will probably be different for each install.

          Cheers,
          Paul



          Click to visit: www.sbsmarthomes.com
          Santa Barbara Smarthomes

          Authorized Russound Dealer & Installer

          Personal HA Website

          HomeSeer User Profile

          Comment


            #6
            Thanks Paul,

            Your post to my question was a BIG relief.

            if you also want to use the A-Bus for background music this will add some more complexity (how do you select sources on the newer A-Bus gear... is it with the IR remote?).
            Yes it is the same Russound A-Bus KP2 key pad that is part of your 4 pair switch photographed somewere in your post. It has IR to contolr Volume, changes source etc and also come with a IR remote (learning)

            Do you think I can Connect Ocelet (IR) to the 1 or 4 source A-Bus hub (something simialr of what your have) and then based on where I am issuing the Voice Command from turn the keypad On to say source 1 that has HS voice with a set volume level. The other zone Keypad remains unchanged.

            Thanks,
            Shaurya

            Comment


              #7
              Originally posted by shaurya
              Do you think I can Connect Ocelet (IR) to the 1 or 4 source A-Bus hub (something simialr of what your have) and then based on where I am issuing the Voice Command from turn the keypad On to say source 1 that has HS voice with a set volume level. The other zone Keypad remains unchanged.
              I haven't done this, so my answer is just opinion/speculation:

              Having the Ocelot's IR output control the A-Bus keypads seems feasible, but you will need to get IR emitters from the Ocelot back to each room where the keypads are. These emiters would then need to be stuck on the A-Bus keypads IR port (which will probably look bad), or they would have to be placed somewhere else in the room pointing at the keypad so it picks up the IR signal.

              If the IR emitter is placed elsewhere in the room (not on the keypad itself), you run the risk of people standing between the emitter and keypad and blocking the IR signal which I feel would be a real problem.

              I guess my answer is that it may work, but it's not an approach I would take...

              Paul

              Click to visit: www.sbsmarthomes.com
              Santa Barbara Smarthomes

              Authorized Russound Dealer & Installer

              Personal HA Website

              HomeSeer User Profile

              Comment

              Working...
              X