K4700 Loudspeaker protector - new way of connectivity

Kits Audio Hi Fi Projects
1

Dear Velleman group,

I’m using your K4700 kit for loudspeaker pretection very often. Now I have situation which I need to solve on the right way. Please read real carefully all details…

Facts:

  • I have two (2) toroidal transformers.
  • Every channel has it’s own transformer.
  • Every channel has symetrical power supply (now it’s not important but it’s +50/ - 50 Volts).
  • Every transformer and power supply has it’s own GND point.
  • It means that I have 2 GND points (each channel has one)
  • On K4700 we have ONLY one GND point.
  • K4700 is designed to protect both channels (L and R)

Question…

How to connect GNDs from both channels to this one point on K4700 ?

Now I have problem. :cry:

Pleas help if you can…

Thanks, regards,

Boris

2

To avoid hum loops, we’d recommend to use two K4700 units.

3

Dear Velleman group,

Thank you for your response, and I’ll do like you said. I will use 2 pieces of K4700 kits.

Now, I have further questions…

If I use one K4700 for one channel and the second K4700 for the other channel is it possible to use one relais for A pair of speakers and the second for B pair of speakers on one PCB.

You know that you have 2 relais on each PCB. I would like to put switch in +V segment of each relais (on one PCB one relais for A pair of speakers, one relais for the B pair of speakers for example for right channnel). The other PCB is the same for left channel ejust to ensure the management of loudspeakers connectors.

So my question is: IS IT POSSIBLE TO PUT SWITCH IN +V SUPPLY OF EACH RELAIS ?Thank you, regards,

Boris