HD Music Streaming over Powerline Adapter

I guess the issue with the filter 'sucking to life' out of the music would be because the choke used in the filter is tending to resist sharp changes in current demands. This could be because the choke is has not been designed to cope with high current demands i.e. thinner wire, bad matching of the various elements in the choke (to keep the cost down). What ever, the better solution, to my mind, would be to ensure that the caps used in the equipment PSU are of large enough capacity to maintain a smooth delivery even if there's a short duration high demand. No?

Indeed, I would be one of those people, and my view is not confined to Naim equipment either, though more aimed at the filters; mains cables of a high standard, but without loads filter-type stuff I'm fine with.  

I have a question though.  When I decided that the filtered mains block I had installed did make a difference, but not one that I wanted, I decided to reverse the arrangement.  I hatched the idea to put all the SMPS stuff, PC, TV etc in the filtered block, the theory being this may prevent the noise they generate getting back in to the mains supply.  Even the fridge is plugged into a filter / surge protector.  I've never looked back since taking the filtered block away from the stereo, much better without it.  But does this idea that filtered blocks reduce noise being fed back into the mains supply actually hold water?

For simple symmetric LC filters (which are the type most commonly used in cheap filtered mains blocks such as the Tacima 926), yes.

In fact I use 2 Tacima blocks in just that way.

Have to admit that I do the same too ... stick stuff that I know is likely to be electrically noisy onto filtered feeds to try to prevent noise going back onto the mains...

Phil

Steve,

That was my original conjecture as well.

Experimentation with mains filters using heavier common mode chokes wound from 2.5mm sq wire didn't improve matters much.  However instead of using capacitors to filter differential mode interference (bridging L-N, L-E, N-E), using a large air cored differential mode choke (L-N only, also wound from 2.5mm sq wire) gave a much better result - sufficient reduction of RFI while keeping the vitality in the music.

I won't discuss further details here, as to do so would violate forum rules.

Although just using a DM choke in series with the mains isn't itself a RFI filter, it does increase the source impedance of the RFI and this allows the RFI control measures within the equippement itself to work more effectively.

So my observation is that the problem seems to arise when the capacitors of the mains filter are 'seen' (electrically speaking!) by the transformer in the equipment's power supply.  I haven't conducted any real tests to identify the cause, but there are some obvious candidates for this effect.

Thanks, Huge.  Some incarnation from the Tacima range is what I have been using too.  Sometimes it's just nice to know you're not alone in an area of obsession that is judged by most civilians to be complete madness.

That doesn't prove that it isn't madness!   It may be that the madness is infectious and spread via this forum.

Steve large psu electrolytic caps have a number problems, one of which is that they do not behave the same way at HF as they do at mains frequencies.  If you look at my earlier post I spoke about bypassing the large caps with smaller caps which will have a better HF response.  I would not be surprised if NAIM regularly did this but I suspect the mass market manufacturers don't

I wondered when someone would mention this 'sucking out the life' issue.  To me this is another one of those HiFi myths, I say myth because it has never been demonstrated to me.  SQ is something we cannot easily determine objectively, so it might be that we get used to RF being passed through the PSUs of our HiFi and might even prefer it to the same system with the RF removed.  Could this be the cause of the 'sucking out the life issue'?  Who knows.  I have never been 100% convinced that RFI degrades SQ anyway.  I guess one problem is how on earth do we test for it?  How do we quantify the RF getting into our kit?

It is IMHO more likely to be cheap caps that could cause any nasty problems in mains filters.  The advantage of building filters yourself is that you can use high quality components.  My chokes are made using a chunky ferrite rod and quite thick enamelled copper.  Caps are always problematical and manufacturers tend to use ones that are cheap, or economical as they would say.  As an example if a 60uF cap was required then the average manufacturer would use an electrolytic cap that would cost pence and not a polyprop cap that would cost £20-£30.  If this were just a bypass cap it might not be too significant, but if your precious analog signal was going through this cap then believe me the difference would be audible - and that is just one component.  So use high quality caps.

Listening with or without mains filters I can detect no 'life sucking' from the sound emerging from my speakers using a variety of filters and mains treatments.  If I was to be completely honest I might also admit to never having heard a huge (or even very small) change to SQ when using a mains filter to eliminate RFI.  But then I was never convinced enough to spend hundreds of pounds on blocks of some exotic wood that when spread round my music room was guaranteed to transform my HiFi.  Nor even a few quid on magic marker pens for CDs that promised the same for cheap and awful CD based systems.

I will tell you something though; if you want to spend money on improving the SQ of your current and future systems then get your room acoustic treatment done.  Believe me you will notice a vast improvement.

As I have gotten older I now find it much easier to sit and listening to my music rather than being analytical about it,  Heavens above I can now even listen to Spotify through my UnitiLite - as long as the sound is not too high!

A little aside:  I was once reading the user reviews of mains treatment products on the a famous website, specifically the power cords they did at the time.  One idiot had written in to say that he had spent approx. £50 on a mains cable for his computer and was overwhelmed.  The sound now emanating from his computer speakers was now much better than his mates expensive HiFi separates system.  This just proves how difficult it is to make judgements about SQ.

ps I originally put the name of the website company & the mains cable manuf. but decided that the forum thought police would not be happy with it and so removed it.