Understanding audio splitter in reverse

[user789]

I am trying to get more practical understanding here.

There’s a 3.5mm audio Y splitter available on amazon. It’s main purpose is to split the output of any audio device that sends audio signal on 3.5mm Line out port into two.





However if I understand correctly, it’s bidirectional as far as wiring is concerned. So if I use it in reverse as a mixer between my PC and TV and share the same speaker will it create harm to the internal amplifier circuit on PC and/or TV?

Now the output of say TV headphone out also goes into the Line-Out on PC while PC line out also sends signal on the same wire.

I am trying to understand if such a configuration is harmless and supported.
Thanks.

 

[Martaine2005]

These are just wired in parallel.
It will work both ways.

You obviously won’t be able to adjust each signal like a dedicated mixer will.

Martin

 

[AnalogKid]

Depending on the output stages of the two devices being combined in the cable, things might not work well at all. The output impedance of a music player or whatever can be very low, much lower than the 60 ohms of so impedance of a pair of earbuds. Thus, each output can present what looks like a strange type of short circuit, one that is a very low impedance but has a varying voltage to it.

A Y cable made specifically to combine signals will have fixed resistors built in to prevent this problem.

ak

 

[crutschow]

Yes, as AK stated, connecting two outputs in parallel should not be done without resistors to isolate the two outputs.

 

[Alec_t]

If you can dismantle the two sockets to get access to the internal wiring, there is likely enough space to solder in a series resistor in each.

 

[AnalogKid]

Or two resistors.

It is not clear from the posts if the cable splits the stereo plug into two mono jacks (one left, one right), or if it is a true splitter with two stereo jacks. If the latter, then each jack needs two resistors, one for each channel.

ak

 

[user789]

If I understand correctly, it's a true stereo splitter. Both L + R are split into two lines. However it's going to be very small sized so it might be using insulated wire inside. DIY is beyond my scope at this stage. Also I think it's all molded into one piece.
I have decided to refrain from using it as a mixer kind of cable. I wanted to share my speaker between two outputs. I can get another speaker in the cost of a basic audio mixer device. In my country the 3.5mm switcher is available, but only as an imported product on local amazon and hence very expensive.

So I will eventually opt for a separate speaker to be connected to the TV headphone out.
Thank you all for guiding me. Best regards.