diy box construction: input rca L+R / output rca L+R+SUB

[alexandrotri]

Hi all,
i need to build a passive box to split a stereo signal to a 2.1 signal (left + right + subwoofer).
It's possible?

Here a little scheme of what i want to do

The yellow area is the box i want to build. I don't know how to correct split the signal and what kind of components i need to do it.
Can anyone help me?

TY in advance for Your precious help.

(sorry for my english: it's not my language)

 

[picowallspeaker]

RCA means line level
Active means that it has to be powered ( by electricitiy)

Probably you need an active crossover !
Very simple ones are found in PC 2.1 systems, where the sub output might be derived from amplifier's output.
The active version would include a [ potentiometer for volume control ] buffer then a quad OP-Amp to perform the mixing and the lowpass.
High pass for the satellites is performed by capacitor at the amplifier's input

 

[rayma]

i need to build a passive box to split a stereo signal to a 2.1 signal (left + right + subwoofer).

The minimum circuit is to connect each L and R input to the single sub output with a series 10k resistor on each.
Your active sub has a volume control to match levels, and a filter.
If you want to filter the bass from your main speakers, add a series capacitor between each channel's input and output.
The capacitor value would depend on the filter frequency and load impedance.
There are better ways to do all of this, but they are much more complex. Do you have any experience in building circuits?

 

[alexandrotri]

First of all thanks to picowallspeaker and rayma for reply: I think rayma focus the situation.

I don't have experience in building circuits but i can learn (I have quite good manual ability).
I don't have theoretical basis in that argument: this is my biggest problem!
🙁


So this scheme is right?

Why 10k resistor? Is a universal value for that kind of connection?

Rayma said that there are better ways to do that: can you suggest me something better?

TY