JaZZ
Headphoneus Supremus
Rob's statements say nothing else but that you can renounce ferrited dual-BNC cables between M Scaler and DAC if you feed the M Scaler with battery power, hence break the loop via ground connection. This explicitly addresses the RFI from the M Scaler reaching the DAC via dual-BNC cables.I‘ve read this thread from the very beginning and I think some things might be being taken out of context.
There is noise generated by the MScaler itself which is attenuated internally but some is still transmitted over the BNC connection.
Using grounded power supplies can make this worse as unattenuated RFI can bypass the BNC and also enter the DAC via ground, and then possibly even exit the DAC and loop back to the MScaler as well. This is the worst scenario of all.
A ground lifted supply, like the stock supply, can help dampen these loops as they will be attenuatuated by a longer high impedance loop via neutral. A battery Power supply detached from its charger will prevent these loops altogether, avoiding the worst case situation.
But apart from avoiding loops, power supplies won’t do anything for the more limited RFI Generated by the MScaler itself and transmitted directly via the BNC.
At least that’s what I have taken from the multiple discussions about this issue.
So if I have interpreted it correctly, ferrited cables still help with the BNC transmitted noise. That isn’t to say that non-DIY BNC options are not grossly over priced. But let’s not get that confused with helpful safety advice of avoiding putting too much voltage into your loved devices when exploring battery power supply options.
As AndrewOld has just quoted (and myself a few pages before):
But if you want to almost completely isolate the M scaler from the DAC then use a battery power bank (so long as you site it correctly) - then the loop impedance becomes very high, and then the BNC cables no longer have an impact on SQ as no current can now flow as there is no longer a loop. Is this something I do in practice - no - the difference isn't large enough to bother with charging batteries. At the end of the day I just want to simply enjoy my music more, and I don't need to go to silly lengths to do that.
The M scaler is helped by using a battery, as it eliminates the 2GHz ground return currents, solving at a stroke the BNC cabling issue.
In short: The RFI travelling through the dual-BNC cables' ground connection is blocked if there's no loop via power-supply ground connection.
Now that's the theory, and I would like to have it confirmed by users who have both Wave cables and power banks at their disposal. This to explore the possibility of further improving the sound with ferrites on the M Scaler's power cable. I don't like the idea of charging batteries on a daily basis and am skeptical towards leaving them plugged in during listening to music, as that would create the loop again that should be avoided – as I see it. I would have chosen the OptoDX system if I could live with batteries, but the Wave cables serve me well.
In this context I don't like Andrew's repeated attacks against Nick, who is virtually doomed to stay silent. They're absolutely unjustified, every Head-Fier can choose her-/himself if she/he prefers this solution despite the higher price.
Last edited: