What is the board supposed to do?
Is the jack socket for input or output or power supply?

 

Hard to give a solution when you show nothing about the boards operation.
The board's picture tells us very little about what it does.

 

What is the board supposed to do?
Is the jack socket for input or output or power supply?

It's a Bose mini link board....jack socket is for input aux... thank you...
I want to connect this output to my power amplifier....

 

Hard to give a solution when you show nothing about the boards operation.
The board's picture tells us very little about what it does.

Sorry..sir. this is a a Bose minilink board I got it from scrapyard.... it's working... there is no common ground for output...
.I tried to connect from speaker output but.. it's not working well... please help thank you

 

.I tried to connect from speaker output but.. it's not working well.

Exactly how did you connect it, and describe what "not working well" sounds like.

 

Exactly how did you connect it, and describe what "not working well" sounds like.

This board ( shows in pic) sound output to a power amplifier ... board SOUND output is like L+ L- AND R+ R -...... THERE IS NO COMMON GROUND...SO WHEN IT'S CONNECTING TO A POWER AMPLIFIER... SOUND MUSIC S NOT GOOD ... DISTORTION

 

View attachment 340047

Bose minilink board...

 

Try three 10 μF 25 V capacitors, one in series with the left channel, one in series with the right channel, and one between the two COMMON.

 

Try three 10 μF 25 V capacitors, one in series with the left channel, one in series with the right channel, and one between the two COMMON.

Thank you I will try

 

Thank you I will try

Drawing or any pics please.. Thank you

 

You many need to use two audio transformers to go from the bridge (differential) output to the single-ended ground connection to your amp.

 

You many need to use two audio transformers to go from the bridge (differential) output to the single-ended ground connection to your amp.

Drawing please... thank you sir

 

O

View attachment 340047

Obviously, its a Bridge output., there is no ground.
Presuming that your Power Amp will have > 100 K as input impedence, the simplest way is to take the speaker output through a 1 uF non polarised capacitor from 1 terminal of each speaker and Ground.
Include a 10:1 resistor attenuator to avoid overloading the input to the Power amp.

The next is Phase balance. Input the same signal to both the Bose card inputs. Connect the attenuator outputs to a single channel of the power amp. Without adjusting any control, change the capacitor connection of 1 speaker terminal to the other.
If the sound is louder, then these are the required connections. If the sound is lower, revert back to the original connections.
Thats it.

 

O

Obviously, its a Bridge output., there is no ground.
Presuming that your Power Amp will have > 100 K as input impedence, the simplest way is to take the speaker output through a 1 uF non polarised capacitor from 1 terminal of each speaker and Ground.
Include a 10:1 resistor attenuator to avoid overloading the input to the Power amp.

The next is Phase balance. Input the same signal to both the Bose card inputs. Connect the attenuator outputs to a single channel of the power amp. Without adjusting any control, change the capacitor connection of 1 speaker terminal to the other.
If the sound is louder, then these are the required connections. If the sound is lower, revert back to the original connections.
Thats it.

Thank you sir

 

Drawing please... thank you sir

Don't really need a connection one.

Example Audio Transformer High Efficiency Audio Isolation Transformers 1300 : 8 Ohm for Voltage Amplification below:
The 8 ohm transformer winding connects to the speaker outputs, and the 1300 ohm transformer winding goes to the amp.
That connection reduces the speaker output voltage by about a factor of 12 to the amp input so you shouldn't need an attenuator.

 

An opamp configured as a differential amp could also work.

 

An opamp configured as a differential amp could also work.

Thank you sir