Скачать или смотреть Active Direct Box: Ground lift does not fix ground loop!

BEWARE TO THE BUYER! READ!

This is a Samson S-Direct Plus, an active stereo di box. I use it in between my laptop's stereo headphone jack to my mackie mr5's to get rid of that annoying chirping/static sound from when the laptop is plugged into it's power supply to charge the battery. Without the DI box between the speakers the noise is unbearable for monitoring. With it gets rid of the 60HZ buzz, but it only MINIMIZES the PSU noise. i use my multimeter and measured a 0 volt potential with the ground lift button on the back of the unit UN-depressed, and when I depress it to lift the ground, I found there is still about a 5kohm resistance between pin 1 and the unbalanced shield ground, SO IT IS NOT A TRUE GROUND LIFT!

So i cracked this thing open and to my surprise, there is NO ISOLATION TRANSFORMER!

I put a simple Hosa adapter that physically lifts pin 1 for ground and hey NO MORE PSU NOISE!

Just be aware, cheap ACTIVE DI boxes don't offer shit for electrical isolation!! You would be better off with a quality PASSIVE DI box