Active interconnect cable

Dear Forum Members!
I found an active cable solution recommended for connecting instruments.
I think the cable inhibits high frequency attenuation.
Is that so?
How do you do it?
Is it recommended for good quality connection of audio devices, cheap?
I tried to show how the cable shielding capacity cuts higher frequencies ...
Thank you for your answers!
 

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This is a real problem at radio frequencies(up in the mhz range) but any cable that rolls off high frequencies in the audio spectrum is very poorly designed or grossly undersized. Just buy quality cables and this won't be an issue.
 
The circuit works by driving the shield of the cable with the same signal voltage as is applied to in the inner conductor.

The shield is ungrounded and relies on the low output impedance of the opamp for its effectiveness. By driving the shield with the same voltage as the wanted signal there is in effect no voltage differential between the two and hence the capacitance between the shield and inner conductor can now cause no HF loss... in theory 😉
 
The circuit works by driving the shield of the cable with the same signal voltage as is applied to in the inner conductor.

The shield is ungrounded and relies on the low output impedance of the opamp for its effectiveness. By driving the shield with the same voltage as the wanted signal there is in effect no voltage differential between the two and hence the capacitance between the shield and inner conductor can now cause no HF loss... in theory 😉

I thought it would happen that way, but technically I couldn’t deduce it. 🙁
After all, an experiment doesn’t cost much, you can even measure transmission changes, if any.
 
The opamp is shown running off single rail which makes it all a little harder to grasp. The input signal is applied to the opamp which is configured as a unity gain buffer. The opamp output then drives the shield.

The power supply needs to be floating in this example (such as a 9 volt battery) because you can not connect the opamp negative to the signal zero volt line.

I first came across this technique many many years ago in Elektor magazine as I recall.