Re: Use of Audio Matrix Mixers in Home Automation

[Marc F Hult <MFHult@xxxxxxxxxxxxxxxxxxxxx>]

On Mon, 26 Sep 2005 04:10:18 GMT, "Solo Rider" <none@xxxxxxxxxxx> wrote in
message  <KwKZe.367747$_o.196369@attbi_s71>:

>
>"Marc F Hult" <MFHult@xxxxxxxxxxxxxxxxxxxxx> wrote in message
>news:e59ej1lre0b8nbs30vfa8jclt56dmd3071@xxxxxxxxxx
>>
>> Seems to me that many of the applications of audio explored in this
>> newsgroup
>>
>> 1) revolve around proprietary, closed systems
>> 2) are limited in what they can do or
>> 3) form separate subsystems that are not well integrated with the HA
>> system
>> as a whole.
>>
>> Here's an approach using audio matrix mixers with voltage controlled
>> amplifiers (VCA's) that is more general and can integrate most all audio
>> parts of a HA system.
>>
>> www.econtrol.org/audio.htm
>>
>> The mixers I use happen to be made by Ivie. I've been satisfied with the
>> quality of their internal VCA's and their equipment in general. They are
>> often available through eBay for dimes on the dollar. But one could also
>> make
>> them from scratch and(or) forego the volume control and easily build
>> switching-only matrices with relays. (There is often/usually more than
one
>> way to control audio volume).
>>
>> Also revised is a discussion of control hardware for 'ActiveKnob'
control:
>>
>> www.econtrol.org/16-pos_ak.htm
>>
>> HTH ... Marc
>> Marc_F_Hult
>> www.ECOntrol.org
>
>If I understood your page properly, it was focused on mixing inputs.  I am
>looking for blending and controlling output, such as overriding  or
>overlaying of music for other inputs.  Any low cost thoughts?

Consider re-reading and thinking about this some more. What is your
understanding of the purpose for the 8 or 14 outputs described if not for
"blending and controlling output, such as overriding  or overlaying of music
for other inputs" ?

Any input can be mixed with any combination of other inputs at any ratio and
routed to any combination of outputs with the level of each input and each
output independently controlled.

Did you find that "a look at the feature list and block diagram [was]
particularly useful" ?  http://www.ivie.com/pdf/884Lit.pdf

The concept of a matrix mixer may take a few minutes to digest and to
separate from other functions included in commercial mixers such as gating,
muting and programming, but it is a powerful concept that can be home-brewed
using either mechanical relays and op amps (without level control), discrete
semiconductors, IC's, or special-purpose modules.

Marc
Marc_F_Hult
www.ECOntrol.org