The Hugo of streaming?

Simon-in-Suffolk posted:

All ferrites stop is common mode high frequency currents circulating along the wire(s). It is a legal requirement in some cases so as to impede and control EMC. However the levels we are talking here are I suspect well below the legal EMC thresholds. If these beads affect the sound in any way then you are experiencing the effects of RFI on your audio system... however if you prefer the sound from your system with radio  frequency noise .. then arguably you could say it not RF  interference as the RF noise distortion is adding to your enjoyment. RF noise can have wierd  effects on audio circuits and how we hear the audio from them.

Hi Simon,

If you fancy a trip over to Head-Fi in their high end hifi forum they have a thread on the Blu II which is mainly about ferrites - you might enjoy it.

In this case I just find it interesting that these ferrites are on a DC cable.

I absolutely agree that RF, and I suspect other pollution, can act like spice; that is to some it will be welcome, to others not so much.

However, I am not sure that what I am hearing with a DC cable is quiet this straight forward, either way I thought the downside far outweighed any subtle positives.


Hi Mr U,  I've read your posts but am not sure what/where this assumed RFI or whatever noise is coming from,  with that we have a better idea what frequency we are working with.   Ferrite suppression is not as straightforward as just clipping one (or more) from the DIY store on a cable.   There are many different compound mixes & each is designed to operate in a specific frequency range.     Most of the general purpose ferrite beads you buy from high street & www stores are a mix called N30 or similar,  their max impedance is apr 400MHz & are practically ineffective below 1MHz.   

FWIW  -  I use one N30 on each of my ethernet branches & a mix number 75 on both 230vAC & DC sides of my SMPS's.    Mix 75 has a max impedance at 1.8MHz & covers a range from 100kHz to 10MHz & is more suitable for the SMPS switching frequency range.  

Hi Mike,

I agree.

In my case I simply bought the cheapest clip on ferrites I could find on Amazon. These are from a company called Topnius and are described as 'High Frequency'. I have dropped them an email to try and find out the spec.

Currently I am doing a LOT more reading and will be buying some different ferrites to experiment in due course.

I was heartened by Rob Watts stating that ferrites in a digital cable can have no detrimental effect (this is probably a gross simplification) and liked that effect on my spdif cable. He recommended specific ferrites, but that was in the context of the Blu II and Dave.

I have read many posts here by people, such as yourself & Simon, who are knowledgeable in this area and thank you for your thoughts and advice.


I tried a different DIY cable for the DC power between LPS1-1.2/uR/IR, which is another nice success and worth a shout out. It is made from the Van den Hul 'D-501 Hybrid' (D-502 is the twin TT phono-wire version).  25.4 AWG SPC wire with a conductive carbon film and SPC shield around it! The  result gives up a little of the 'CAT7/8 DC soundstage' for a very 'sweet and  forgiving' sound with PRaT highlighted (very musical, NAIM-like result).  EUR 25/M from the big site bulk seller and worth it. I am using it in the counter intuitive 'high inductance' configuration but works great! 1m length with the two signal conductors joined together, one for +ve & and one for -ve. The two shields & gnd wire are tied together but left floating at both ends.



Topnisus got back to me saying, ' Hi friend, these ferrite cores could be for EMC interference that frequencies range around 1-1000MHZ. '


I found these very effective on my Mark Grant copper spdifs. That said, the treble becomes less edgy (sounds more realistic) but also moves further back into the mix.

A friend came over on Saturday for a mini-bakeoff comparing DACs, but also bought three spdifs: Audionote Pallas Black (£5k); Audionote Pallas (£3k); and, a triple shielded studio spdif (£15).

I would love to say that the expensive spdifs were foo, I DO think they are rediculously priced, BUT ....they both give all the positives of the cables I have heard with none of the negatives. They do sound different and it would take time to decide which I preferred.

The studio spdif was as good as my Mark Grant + ferrites, but in a different way. I am going to play with it further by adding some ferrites.



Some report good results using different ferrites. My experience is that I always prefer NOT having any in place, the effect is immediate and inferior in my opinion.

WRT CAT7 cables:
Ugreen do a 26awg flat cable. I tried this in my digital back end, and preferred it. Replacing the Ibra in my digital front end with the Ugreen was subtle, but I preferred the Ibra.

One cable that has been reported as being above all the CAT7s I have mentioned for DC are the AudioQuest network cables. There was a tear down of the cables which showed that the AQ network cables use solid metal NOT stranded. I do have a Cinnamon which is the last network cable feeding my ultraRendu, this does give a small lift in the SQ over the others I have tried. I am tempted to buy and try a couple for a DC experiment.





Mr Underhill posted:


Topnisus got back to me saying, ' Hi friend, these ferrite cores could be for EMC interference that frequencies range around 1-1000MHZ. ' 

A vague & frankly I can't believe that answer I'm afraid,  no ferrite covers the 1-1000MHz range.  Attached pic is a basic graph that shows some of the popular Fair Rite mixes used for suppression. 

No problems Mr U.    However if I may add some more:   I used that Fair Rite block graph simply because its easier to understand than up&down wiggly line graphs.    Fair Rite is a USA cmpy & their products, or at least the full range, are not so easily found in Europe.   

I don't have S/PDIF so am not sure what you are trying to do,  you don't say what frequency range you are suppressing & that might make life a lot easier to know that,  however it is OK to use two different clamps on the same cable to cover a wider range,  

Hi Mike,

The answer is - I don't know.

You are right on the FR, only ones I can find are 31s.

The idea came from a thread that Rob Watts started on the Blu II. That is connected via two coax to the Dave. There was shown to be a lift in performance by adding spdifs to those cables, two particular ones were mentioned. However, that was in that context.

I decided to add a couple of ferrites to my DDC to DAC spdif and liked the result.

My intention had been to buy a selection and do a heuristic exercise. As it happens the supply via Amazon is rather limited.

Currently I am listening to a studio triple shielded spdif, which I quiet like, but prefer with a number of Topnisus added.

I am looking at a few Electromagnetic Field detectors, but I am not convinced of their efficacy.




Hi Mike,

Thought I would do some copy & paste from the Rob Watts BluII thread that led me to try the ferrites - apologies, but it does add some grist:

Anyway, I spent the whole of last afternoon, and much of Friday evening on it. About half-way through, I lost the will to live struggling to hear any consistent differences. But at the end it proved worth it.

So what did I do. Firstly listen to some BNC cables, and I bought these:
1M gold BNC
2M gold BNC

After a lot of initial inconsistency, a number of rules became apparent:
1. Do not loop up unused cable - it sounds better stretched out.
2. Cables must not touch other cables (they can touch one another though - just avoid mains and other digital cables).

So which one sounded the best? Well it actually was a struggle hearing consistent differences, particularly bearing in mind comment 2 - how one placed the cables is almost as important as the actual cable.
In the end, the 2M BNC was best - it sounded a little deeper in depth than the 1M, and a tad warmer. The 5M was slightly brighter than the 2M, and had slightly worse depth.

The changes are small, level 1 - that is only audible by a careful AB listening test. So at that point, I was disappointed, as 3 hours work gave no big improvement.

But there was something else to try. Now I am convinced that the RF qualities of the cable is not too important as quality standard RG59/U sounds identical to exotic PTFE insulated cables - the only difference being length. And increasing length increases inductance, which reduces RF ground currents going into Dave - and that's what we want to do. But there is a better way of increasing the common mode impedance than simply adding length - and that's ferrites that clamp over the cable. So I had bought some ferrites to try too:

Ferrite clamp, 5mm
Ferrite clamp, 7.5mm

The clamp simply clip together and clamp over the cable. A plastic key is used to unlock the clamp.

Initially I tried the 7.5 mm, with one on each end of the cable. Boy what a change! This was not something small, struggling to hear a difference - it was a lot darker, with better instrument separation and focus - all classic signs of lower RF noise. And it was a lot darker (to my ears) - so much so that I suspect some people may find it too much of a change - but believe me run with it, you will just need to make your system more transparent or brighten it up with EQ, speaker placement, different headphones etc. With all of my DAC's, jitter is not an issue, so the only thing to worry about is RF noise creating more noise floor modulation. The rule is simple - if the digital source sounds brighter, it is categorically worse, even if you think it is more transparent, as it isn't. And if the digital source sounds too warm, then change the rest of your system to make it brighter. Otherwise, you will not make progress towards truly transparent sound.

The 7.5mm sounded better than the 5mm. Also it sounds better with both two 7.5 mm at Dave end. I only bought 4 of the 7.5mm, so I need to order some more. CPC have low stock, but you can buy from Farnell:

I will try more, but I suspect 4 on each cable (Dave side) will be the best. Ferrite treated cables also reduced the length effect, so the difference from 1M to 2M was smaller.

In the evening I used the cable on my main system, just for pleasure - and immediately I could tell it was a lot better - warmer and darker, with better depth. I also found that I could listen at louder levels - this is classic RF noise effects.

To conclude - don't bother with expensive BNC - just use quality RF RG59/U. But ferrite clamps on Dave side is a must.


Some additional pearls picked from different posts:

The problem RF frequency range is 50 kHz to well over 1 GHz... But my guess is, in this application, 100 MHz is the key. I did try the 5 mm ones too, these have a higher impedance, but was not as beneficial (SQ wise) as the 7.5 mm ones, and I guess these have a higher resonance frequency. Ferrites are not like inductors, in that the the series resistance increases at RF, so they provide better attenuation above resonance.

The issue here is not so much RF noise per se but when it is correlated with the wanted music signal. What the ferrites do is reduce common mode RF currents from entering Dave's ground plane. My thinking is that the correlated RF gets directly demodulated into a distorted audio signal, and this is responsible for the improvement in depth that I have heard with this treatment. The extra warmth is just straight forward noise floor modulation due to random RF noise inter-modulating with the analogue electronics within Dave. So if the common mode impedance was infinite, then we would have effectively isolated it completely from upsetting the ground plane.

Ferrites on digital cables have absolutely no down-side technically. But for analogue cables, proceed with extreme care, as ferrites, like all magnetic materials, have non-linearities, and the benefits may be be much smaller than the problems of the non-linearities. Principally we have two problems:
1. Hysteresis - this will cause straightforward high frequency distortion, and timing distortion, as signal delays depend upon previous activity. Both effects are highly audible.
2. Inductor saturation. As current flows in an inductor, the inductance value reduces with current; this in turn changes the phase angle, so the delay varies with current amplitude. This creates PIM (phase intermodulation distortion) and also creates non-linear timing errors too. Again, this effect is highly audible with large currents (loudspeaker outputs) on both inductors and in-circuit ferrites.

Experience has taught me not to use inductors or ferrite beads in-circuit with analogue, because of these problems, as they are directly measurable (with loudspeaker outputs), and certainly audible. The large ferrite cylinders are less of a problem, but nonetheless don't assume that a ferrite that is good on digital will be equally good on analogue.

As too which ferrite is best, then for sure the warmer, smoother or softer sounding is the more transparent, as the mechanism for changing the sound is RF noise creating noise floor modulation - and more noise modulation always sounds brighter. Moreover, it's very easy to confuse a bright sound with more transparency.


Hi again Mr U;  I read the words of wisdom from Mr Watts & looked at the ferrite spec he is using.  They are made by Wurth (very reputable brand) & although they claim they work across 1-1000MHz,  they are pretty ineffective at the 1mHz end & is more useful between 30 & 1000MHz,  peaking around 200MHz.   But spec's aside Ron says that the 100MHz region is the key & these ferrites are perfect for that,  so I would go with the same from Farnell & order the split clamp that fits your cable diameter.

Haven't reported much here recently. In January '17 i thought I was pretty much done:

In fact things moved on, a LOT.

But, I do think I have more or less reached a plateau. I have sold my Border Patrol SE DAC, and what an excellent box it is. Really, this thing was a step change for me in digital reproduction. However, a friend bought over a couple of Audionote DACs, and I was smitten. I am now using a Blackgate upgraded Audionote 2.1 and it is superb.

WRT Coax: I have returned to using my Mark Grant Oyaide, with three ferrites attached. Although I have to say the Audionote Black & Black Pallas are playing on my mind, stupidly expensive!

WRT CAT7 PoE: The source of the idea for this has moved on to using a pair of altered USB hubs to send +ve and -ve via two different cable using all eight wires, and claims a step change. His observations have been solid over the last few years I have followed his posts and so I am buying a pair of hubs from him, as it all looks a bit fiddly - he has published all the steps with photos for people to do themselves. He has found that the cables that work best for him are the Audioquests. Interestingly they have been found to use solid wire, rather than stranded. As you go up the price range the percentage of silver goes up. This echoes the Audionote Black & Black Pallas , which use Palladium covered extruded solid silver - hence the cost.

As for my current sound quality, it is excellent, never better; the ultraRendu is singing .....but, it is sorting out the power that has proved to be the primary issue for me, including grounding.


Skimming through the ND555 impressions thread the following comment by Clive B caught my attention.  I have been thinking about something similar while trying different DC cables. I have noticed this with some of the DC cables I have tried with the uR/IR/LPS 1.2 ->DAC -V1 as described in the PC based schematic on the previous page..

Quote (Clive B)

"Something I've noticed before with significant upgrades is how it feels as if the music is being slowed down - and that was my first impression, as though the music was being stretched to allow the rests between notes to be fully heard."

My observations on the cables used for the DC power.

1. These cables  'slow down' music ( 'suspend' time illusion) - with nice sound stage focus

1.1 DC/PoE cable -  Ugreen, Tera Grand CAT7 both flat, Supra CAT8

1.2 Van den Hul Integration Hybrid Fusion 24 AWG? Cu/Zn/Ag alloy+carbon film, star quad, triple shielded

2. These cables cause frantic foot tapping (illusion of 'sped up' music) - with reduced sound stage focus

2.1 Cardas Cu 15.5 AWG hook up wire (in twisted pair, or single with or without ferrites)

2.2 Mil-spec wire 22 AWG SPC /PTFE in near star quad

2.3 Van den Hul MC D-501 Hybrid (24 AWG? SPC+Carbon film) one length per leg

2.4 (only from memory, cannot verify)  Gotham GAC-4 Ultra Pro LCOF Cu, 5 shields star quad

I find all of them enjoyable in their own ways.

Hi Brilliant,

Perhaps slow down is his version of the word I use, relaxation. For info:
I replaced the dual Ibras with LT3045, I used for powering my F1, this is the one that gives the biggest bang for buck, with dual AQ Pearl 1.5m. This is the cheapest AQ cable, using just copper. CLEARLY better bass and top end.

The modded PoE extenders have arrived.


Hi B,

Yes, I need to do a bit more with my DC cables!

The PoE extenders are, in a word ....brilliant

They really do take things up a notch in terms of bass extension and noise removal. I am letting them bed in before I write more. If you visited Rob's thread a chap has come up with another way to do this which is cheaper, and I will try:

What I did was tie some simple rj45 keystone tool-less jacks into some dc pigtails ...

Looks a bit more heath-robinson, but may be just as effective.


Mr Underhill posted:

Hi B,

Yes, I need to do a bit more with my DC cables!

The PoE extenders are, in a word ....brilliant

They really do take things up a notch in terms of bass extension and noise removal. I am letting them bed in before I write more. If you visited Rob's thread a chap has come up with another way to do this which is cheaper, and I will try:

What I did was tie some simple rj45 keystone tool-less jacks into some dc pigtails ...

Looks a bit more heath-robinson, but may be just as effective.


I had a peek at usaudiomat thread -great idea, thanks! I guess they only accept 23-24awg wire? I would double up per leg and use a nicer DC connector (not a fan of the molded ones). One could use star quad (buy from Ghent a finished cable and cut it into two, one piece for each end)?

@romaz is back posting at CA in the 'A Novel way..' massive thread he OP'd. This time  about a $93 Intel NUC board with eMMC flash storage, using the TLS custom 6GB Linux OS that fits and completely runs from its 8GB RAM.  His best yet- when powered from the PH SR7. ..

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