karanrai

Multichannel audio in coach and large vehicles

2 posts in this topic

Hi I have a project wherein i need to wire 4 stereo channels playing different music in a bus with 32 seats. Each seat should have a module to select one of the 4 channels and listen to it by plugging headphones in a 3.5 mm jack on the seat module. We have built the music system with 4 stereo outputs and we have also created a small seat module with amplifier which takes in stereo input and sends out amplified stereo output. Now I need help with distributing the audio. If I connect the 4 channels to the 8 wires on a CAT5 cable and run it across the bus, drawing out a parallel connection for every seat and also run 2 seperate wires along for power and ground, which are also drawn out for each seat module, would this method work? Is there a better way to distribute multiple channel audio across 32 seats in a cost effective way?

Additional Info: the input impedance of the amplifier circuit at the seat units is 150k ohm and the length of the bus is 10m. (Around 25m cabling) Would the voltage drop be significant and would it require another amplifier / repeater ?

Share this post


Link to post
Share on other sites

An absolutely awesome question, and an awesome project too!

I'm hoping someone can chime in here (Jester???) re how many times a line level signal may be split, and split, and split again before it runs the source too hot (ie. essentially shorting it out with so many parallel connections).

As for the 25m worth of cabling, I'd dare say the voltage drop would be marginal, though there may be slight interference between channels running down a single cable, as well as possibly picking up interference from the surrounds, including the engine via the power cables running in close proximity with the line level audio.

Anyway, keen to others thoughts, particularly with running so many devices off a single source in parallel.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now