[lojay]

I'm glad you like the Blu2. Your impressions seem to match up with most peoples experiences regarding the bass etc. However, I have not noticed any glare as such (not that I really know what you mean by that). Regarding the ferrites, are you using the recommended 5 per BNC cable?

With the speakers I see that you are using HFC interconnect cables. I personally do not think these interconnects are suitable for use as speaker cables as they are not really designed to carry the current required by the speakers (albeit less than other less efficient speakers). By and large, interconnect cables are supplying a voltage to an amplifier but with no particular regard to current carrying ability being required for the interconnect design. By connecting speakers direct to the Dave you are expecting the interconnect to now carry current as well as transmitting voltage. You might get a better result with less exotic but thicker cables to connect to the speakers.

Thanks Triode. For the sake of not misleading anyone into thinking that the BluDave sounds sub-par with speakers, let me just clarify this. I think the BluDave's improvement with speakers is worth it, but just less significant compared to the improvements it delivers to my headphone setup. There may be be various reasons for this and it will take me some time to bottom these out:

1. As Triode you pointed out, it may be that the HFC RCA cables are the wrong type and capacitance to deliver the current required by the Omega CAMs.

2. The other reason may be that I have no power treatment at home (the UR Helix is plugged into a bog standard wall inlet through a cheap UK to US power adapter) whereas at work, I have a Shunyata Triton connected to a dedicated 20A line (with Furutech power inlets) through a Shunyata Alpha 20A HC PC.

3. It may also be the fact that at work there are more clocks powered by the sCLK-EX and clean LPS power (sMS-200 and modded switch), whereas at home the SOtM sMS-1000SQ is powered by a stock switching supply. This is a stop gap solution pending the delivery of the SR7 linear supplies I am anticipating from Paul Hynes next month.

4. Finally, it may be that the Omegas are not as resolving as the HE90 (which is not impossible).

As to the question of glare, I believe a number of people including Romaz have commented on the glare associated with the stock cables (without ferrite cores). I haven't heard any glare with the HE90 but they are evident when playing string quartets on the BluDave at home in my speaker rig. The Omega CAMs have a tendency to sound a bit lean at times which is cured substantially by good cabling. So I treat this as a cable issue not a BluDave issue. And no, I have not got any ferrites yet.

 

[DaveRedRef-III]

I agree with lojay and Triode about use of HFC cables for this purpose. I have a set here and HFC cables introduce a noticeable drop in volume. Not really what you want to drive speakers.

In regard to using 'ferrites' I would also suggest that the use thereof can be overdone to the point of overcompressing the signal. This is certainly the case with Analogue interconnects. I have not tested their use with Digital interconnects. When it comes to shielding or suppressing EMI/RFI all methods are not equal and ferrites as well as other forms of shielding can interfere with natural eq spectrum, dynamics, pace, and musicality of your system. That darker sound you hear is not less gremlins affecting the sound. It is compression. Like Christer I have worked with compression on mixes for years and you get to know even its more subtle fingerprint over time. If you wish to test this theory. Take the ferrites off, get used to your sound again and then install some demo Jaya's from Vertex AQ. What you will hear is the true sound of lower EMI/RFI and you will notice all the good hifi stuff is not taken away. It's passive shielding. The real sound of RFI/EMI is a high frequency frosting above 10khz. I would say around 12-14khz at a guess. When you take it away, focus, bass, warmth are all improved. This is different to compression which changes the the dynamics and darkens the sound. I'd go as far to say that cable companies are coming up with such exotic and extreme shielding now that they are at risk of overlooking the balance to be had with the affects of introducing compression like this. I know of one leading company that has already over-egged the pudding in this respect with their flagship product. The compression effect is most noticeable on their speaker cables.

So, I bought some 10mm ferrites big enough to go over an 'already reasonably well shielded cable'. This particular shielding was of a design from a previous decade and I wondered if it could be improved. I put 3 ferrites on each (already shielded) analogue interconnect. Two at the amplifier end and one at the Dave end. The sound was immediately darker as expected but there was Circa 70% loss in musicality, whilst dynamics were effected too. I noticed particularly that the unique 'pace of Dave' was now gone. It was like the music was now being dragged along. So I took the ferrite off at each Dave end and got back to 90% normality. I then took off one of the ferrites at the amplifier end and was back to 95%. In the end I took the last ones off and preferred the original sound. To my ears the current shielding of those interconnects was well balanced and I wasted a small amount of money on the ferrites but it was a useful exercise nonetheless.

 

[Articnoise]

I've received the Blu 2 and have tried the BluDave on my speaker rig at home (to Omega CAMs directly with HFC Ultimate Ref RCAs) and headphones at work (to DIYT2 and Sennheiser Orpheus HE90).

I must say that the improvements are immediately noticeable. It seems wrong to put it this way, but the BluDave lifts away the smudge around instruments and voices that was once there with just the Dave. Tonality is richer, with sonic cues presented in a palpable stable and solid sonic image. One way of putting it is that sonic cues which used to sound like they were floating in space with the Dave now sound properly like instruments playing with the musician sitting or standing firmly on the ground. Realism is the word.

To make sure I wasn't hearing things, I did an A-B comparison: I swapped the USB feeding the Blu 2 into the Dave, switched the Dave from BNC to USB mode, and the magic is gone.

I was most impressed with the effect on my headphone rig: I must say that whilst I had to use a tube amplifier with the HE90 headphones, which are very dated by today's standards. It shows that this old system could still scale higher with improvements on the digital front end. I have never heard anything as resolving yet. I listened to the BluDave all day at work (very distracted from it I must say) and brought the BluDave back home. The BluDave directly driving the speakers was less impressive, still very impressive, but I felt the resolution of my headphone setup could not be matched. Might be speaker placement or simply the speakers not up to it, I cannot be sure.

Wth both speakers and headphones another thing that was immediately apparent was the improvement in soundstage, depth and bass. Bass in particular was an area I felt the Dave alone lagged behind other top of the line DACs. I don't think so now. A typical criticism of electrostatic headphones like the HE90 is the lack of bass - I agree with that statement but, for the first time, I consider that it's bass was more than adequate in terms of quantity and viscerality when I was playing Jennifer Warnes' Way Down Deep. It's fair to say the BluDave has turned up the bass a notch or two.

The improvement in depth is very noticeable. I put on Yuja Wang's Rachmaninov (Rhapsody on a Theme of Paganini) and was able to hear for the first time that Yuja's piano was distinctly closer to the audience than the strings. With just the Dave, it seemed that she was much closer to the strings; with the BluDave the focus was much on her which is the point of the recording.

These are my findings so far. In short, the Blu 2 completes the Dave. It's worth it. There are things I could still improve - there's a little bit of glare (interestingly, mainly when I play back CDs). If anyone has extra ferrite cores or cable recommendations do let me know!

T2 and Sennheiser Orpheus HE90 at work - wow!

 

[Malcyg]

Thanks Triode. For the sake of not misleading anyone into thinking that the BluDave sounds sub-par with speakers, let me just clarify this. I think the BluDave's improvement with speakers is worth it, but just less significant compared to the improvements it delivers to my headphone setup. There may be be various reasons for this and it will take me some time to bottom these out:

You certainly should be able to achieve all of the benefits that you can hear through your headphone setup from your speaker set up. There will be a reason that you currently can't and you have the headphone sound quality as a yardstick to match against, which is very helpful. When I got my Blu II, it highlighted deficiencies in my streaming/file playback setup which I hadn't previously realised were there. Comparison against the CD playback as a reference was very helpful in both identifying and eradicating this issue.

I think that the aim of using ferrites - or better BNC cables - is to prevent noise entering the sensitive ground plane of the Dave, but I'm not sure that I understand the benefits of using the ferrites elsewhere, especially the analogue outputs. I haven't tried that myself but the ferrites are quite cheap, so it's worth a try - especially if you can get a key that enables you to remove them again if they make no difference or, as Dave mentioned, you feel that it detracts from the sound quality.

Good luck with it,

Edit - I have a strong suspicion that your speakers will be holding you back. If I am looking at the right speakers, then they retail for approx 10% of the retail price of the BluDave combination. So you have a very high level front end, high level headphones and are relating that sound quality to relatively low end speakers by comparison. It's never likely to stack up.

 

[Malcyg]

The real sound of RFI/EMI is a high frequency frosting above 10khz. I would say around 12-14khz at a guess. When you take it away, focus, bass, warmth are all improved.

That is interesting Dave, we must have similar ears! Prior to utilising the ferrites on the BNC cables, I used to apply a 3.5dB cut in Roon EQ which peaked at 11,750khz and the Q spanned roughly 10-13.5, so your guess is very much in line with my own observation. I no longer apply any EQ since it is not necessary now and, personally, I do find the sound to be more transparent with no EQ applied. I accept that others may not agree with me on that.

 

[DaveRedRef-III]

That's good that the ferrites worked for you in this respect Malc. Shielding from RFI/EMI is definitely a worthwhile goal and my post above was not designed to put people off trying ferrites, only to say that there are side effects if over done. My analogue interconnect experiment was deliberately extreme so as to get to the failing point very quickly. At the time I had long cables on my speakers which again pushes the system to be very critical of experiments on the margin.

For those that haven't really 'heard' or noticed the sound of RFI/EMI in their system a better description would be to imagine the sound of those old oscillators with variable frequency. Imagine the frequency being turned up higher and higher till it is so high you can only just hear it. Then imagine it constantly there whilst you listen to your music. Eventually it annoys you even if you are not actually listening to it. Fatigue eventually sets in and you turn your hifi off. Ferrites and cable shielding can reduce this significantly but they do introduce compression to a greater or lesser degree depending on the level of treatment. That's the darker sound you hear. The peaks are compressed slightly, the energy must go somewhere so it spreads and masks some of you higher frequencies. Shunt mains filters take a different approach. They plug into your mains and act as a magnet for RFI/EMI. They are saying "don't go there, come to me". I prefer it as a neater, less intrusive solution along with reasonably well shielded cables.

 

[marcmccalmont]

Exactly the symptom I had with my Spectral amps fixed with 2 ferrites over each of the balanced output cables

 

[Rob Watts]

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.

 

[Malcyg]

Ferrites on digital cables have absolutely no down-side technically.

I have no idea about the technicalities Rob, but I can detect no adverse impact at all from the ferrites on the BNC cables.

 

[Muataz]

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.

All ferrite are the same ? or they have some spec ?

 

[Triode User]

All ferrite are the same ? or they have some spec ?

Ferrites are not all the same. If you look at a typical suppliers website they will list min frequency, max frequency, Impedance @ 100MHz as well as physical size and whether they are split core, beads, cylindrical etc.

 

[JaZZ]

I have no idea about the technicalities Rob, but I can detect no adverse impact at all from the ferrites on the BNC cables.

That's what Rob has stated (just in case you have misunderstood). Only analogue signals will (audibly) suffer from ferrite cores' saturation and hysteresis effects.

All ferrite are the same? or they have some spec?

They certainly don't all measure exactly the same, but all of them have the same problems to some degree. So it's highly recommended to renounce ferrite cores on analogue cables.

 

[Malcyg]

That's what Rob has stated (just in case you have misunderstood). Only analogue signals will (audibly) suffer from ferrite cores' saturation and hysteresis effects.

Yes, I did get that and that was my expectation to be honest, but I thought that since Rob was speaking from a technical perspective, it may be helpful to confirm that, from a luddites perspective, there was no discernible downside on BNC into Dave - just for a bit of balance.

 

[Paul Bjernklo]

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.

Very interesting Rob. What I don't understand is why you have previously stated on your loudspeaker cables you have ferrites on them on both ends. I bought a few of the ones you recommended on digital cables and used these for my digital inputs to my Hugo 2, and found no negatives, only possibly very slight positives as I use CD/USB as input (not used on optical input obviously for CD which I prefer). I also added some to my power cables and again I can't say it changed the sound either way but will leave them until further testing proves otherwise. I then tried some at loudspeaker cable end (4m long cables) as well and I was very happy as I got the warmer sound which I was after as overall system is somewhat bright due to I think my speakers, and I got no detrimental effect that I could hear. Since that was a great success I thought my flat was EMI/RFI infested so thought I will ferrite everything... I then added some more on the analogue interconnect from Hugo 2 to Benchmark AHB2 power amplifier as well and (at same time) at start of loudspeaker cable out of the power amp, and that really changed the sound taking away higher frequencies too much and I was somewhat puzzled by the sound (possibly sounding compressed). So obviously not what I wanted but don't yet know if issue is with ferrite on the analogue interconnect or speaker cable. Any thoughts or suggestions would be appreciated as you stated you use ferrites on both ends of your loudspeaker cables that you made. Maybe it is all "trial and error"? Thank you. Paul

PS: Love the Hugo 2 . I have amazing transparency, detail but most importantly musicality and "being there". Just trying to improve my overall system and learn more how to do that...

 

[Jawed]

It's occurred to me that some people who prefer a pre-amp between DAVE and their power amp may actually be using the pre-amp as an RFI filter without realising it, implying that the power amp is quite sensitive to RFI.

Now playing: 10,000 Maniacs - You Happy Puppet