[Frameworks] Pageant through a Mackie?

[Kenneth Linehan]

Hi Julia,

I would not recommend connecting your speaker output wires directly to  
the mackie on any of its inputs.  The inputs on your mackie are  
designed to take much lower voltage levels at their inputs and the  
speaker amplifier in your pagent is designed for a very specific load  
that is provided by the attached speaker.  6 ohms as you mentioned.   
If you remove that load from the Pagents audio amplifier, it could  
cause the amp to overheat and result in permanent damage to the  
projectors audio circuitry.

In a pinch you may find that the headphone output could be connected  
to a line input on a mixer, but even this is a problematic solution.   
I'm sure you have used this technique before, since most 16mm  
projectors do not have line level outputs.  It is not ideal from an  
electrical perspective and it often results in an undesirable level of  
distortion in the audio unless the boards input is attenuated  
significantly.  This is due to the same problem of improper voltage  
levels and impedance matching between headphone outputs and line level  
inputs.  But in the case of headphones the levels are much closer than  
that of your 12 watt speaker amp.

There are converter boxes that can attenuate and impedance match  
between a speaker amplifiers output and a line input.  Something like  
this would work well in your situation:  http://www.xantech.com/Audio/AVDistribution/AVDistribution/SLLC1/ 
   There are many products like this on the market, and you should be  
able to find something even cheaper than this, which is probably  
between $40 and $50.  A search for "speaker output to line level  
converter" should summon a lot of commercially available solutions.

If you are at all handy with a soldering iron, you could also make a  
simple attenuation circuit yourself.  I came across this link a while  
back while looking to build line to mic level pads for a preamp.  It  
may help you with your project:  http://www.tkk.fi/Misc/Electronics/circuits/speaker_to_line.html

You will see that the author of this page discusses the problem with  
disconnecting a speaker without creating an alternate load for the  
amp...

Hope this helps.

Ken



On Jan 17, 2011, at 2:25 PM, Julia Nimhuiri wrote:

> Hello Frameworkers,
> I wonder if anyone can tell me; is it ok to use the speaker-out port  
> on a Kodak Pageant to route the sound through a Mackie (or similar)  
> mixer?
> (My idea is to snip the wire that attaches the Pageant speaker,  
> keeping the proprietery phono plug/socket in place and attach a  
> standard phono plug to the end of the wire, running it into a mixer  
> to improve the sound playback quality.) The model is: Pageant. Model  
> AV-126-TR, 12 watts audio output, 6 ohms.
> I'd be very glad if anyone has ideas or has done this themselves and  
> can share their notes.
>
> Thanks!!
>
> Julie
>
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