Speaker noise; Cinema 70s V3 monos 10A PS, fosi power line filter

[Beav1S]

My setup is LS50 metas connected to 2 x v3 monos that share a 10A power supply. The monos are connected via RCA to Marantz Cinema 70.

With Cinema 70 and LS50s there are no noise issues. Throw in the two V3 monos and I get noise only when one is on and one is off. This has been reported and fosi made a filter. I got it yesterday. Adding it did nothing. Did some more testing today and it happens only with the RCA input plugged in.

Is there anything I can try? Is this a ground loop problem or a Fosi problem?

 

[staticV3]

Will you frequently have just one V3 Mono turned on?

In other words: is this worth worrying about?

 

[Petrushka]

Will you frequently have just one V3 Mono turned on?

In other words: is this worth worrying about?

*This power filter effectively addresses any potential noise concerns that may arise when using multiple devices simultaneously, ensuring pristine audio quality*

Oops.

 

[Beav1S]

Well the problem is that the auto function does not switch on and off at exactly the same time, it is very quick and reliable so far but still there is a second or two of this noise every time, which annoys me.

 

[Beav1S]

Also I just unplugged the Marantz from the mains and the problem persists. Unplugging the RCAs from the back of the maratnz has a different noise.I guess the cable becomes an antenna. Unplugging from the v3 monos there is no problem. So my guess is that there is a loop between the monos because the two are connected both via the RCA common and the power supply. I’m guessing within the marantz the signal is single ended and all rca have a common side perhaps via a resistor. Btw the Maranz plug does not have a ground pin.

 

[Rotel75]

For me sharing the power supply is nonsense. The need for the filter is the proof that Fosi made a mistake.

 

[gwing]

Also I just unplugged the Marantz from the mains and the problem persists. Unplugging the RCAs from the back of the maratnz has a different noise.I guess the cable becomes an antenna. Unplugging from the v3 monos there is no problem. So my guess is that there is a loop between the monos because the two are connected both via the RCA common and the power supply. I’m guessing within the marantz the signal is single ended and all rca have a common side perhaps via a resistor. Btw the Maranz plug does not have a ground pin.

Have you tried XLRs?
With RCAs I had problems whatever the amp configuration because of grounding issues but using XLR connections I get zero problems with two V3 monos and a single 10A power supply whether the filter is used or not. To be fair I have now made other improvements as well such as wiring my Wiim Pro+ and PC source into the same network hub but at least it seems to show that my V3 power supply arrangements don't have any inherent problem.

 

[Rotel75]

Would like to use balanced, but my preamp is RCA only.
Either the XLR/balanced technology is hiding/fixing the single power supply issues or Fosi only made the design mistake on RCA.

 

[Clmrt]

Use two individual power supplies?