[STR-1]

I have a Dave and only use headphones (LCD4) with it. Trying to see if the BluDave has as much impact on headphone listening over the Dave by itself. Seems like everyone who has posted here uses it with speakers.

It's outstanding with headphones. I have a Blu 2 on loan and have been using it with my Utopia and LCD-4. This is the first time the LCD-4 has sounded like I always wanted it to, with clarity and dynamics I didn't think it was capable of. Subjectively, the impact of sound quality improvement adding tne Blu 2 was easily greater than the jump from Hugo to DAVE. Sadly, I will have to return the Blu 2 to the dealers early next week, and I am not sure when I will feel able to buy one.

 

[STR-1]

I know it's early days and there aren't too many Blu 2s out there but has anyone experimented with different power cables on it?

 

[Triode User]

I know it's early days and there aren't too many Blu 2s out there but has anyone experimented with different power cables on it?

No, I think it sounds amazing with just stock kettle leads.

 

[DaveRedRef-III]

If any of you guys have got a copy of Isaac Hayes - 'Theme from Shaft' in your collection go dig it out, blow the dust off and let BluDave do its magic. There now that put a smile on your face.

The orchestral soundstage is superb!

Nicely mic'd by the engineer I would say...........It put a smile on my face anyway.

 

[dmance]

No, I think it sounds amazing with just stock kettle leads.

BLU2 is a digital-to-digital device and this is what I would expect. It's only on DACs (where the digital gets converted to analog ) that one must pay attention to anything that may upset or improve the small signal processing. Hence the discussion of the digital cable link from BLU2 to Dave where spurious (analog) noise makes its way to Dave to affect sound.

 

[marcmccalmont]

I know it's early days and there aren't too many Blu 2s out there but has anyone experimented with different power cables on it?

I'm using Pangea AC14SE mkII ($60 us) with very good results and a PS Audio powerplant

 

[dmance]

Regarding the digital cable link from BLU2 to Dave. Has anyone tried a SPDiF Isolator like the iFi SPDiF ? It's $149 and two are needed ...but this must be less hassle than looking for cables that filter spurious analog noise.

[EDIT] ...the iFi Only works to 192khz ...not 384khz like needed. So no-go I suppose.

 

[Triode User]

Regarding the digital cable link from BLU2 to Dave. Has anyone tried a SPDiF Isolator like the iFi SPDiF ? It's $149 and two are needed ...but this must be less hassle than looking for cables that filter spurious analog noise.

[EDIT] ...the iFi Only works to 192khz ...not 384khz like needed. So no-go I suppose.

I can't see any point at all in fiddling or messing with the digital signal from the Blu 2. After all, it goes straight from the Blu 2 to the Dave with only a cable in between.

Also, just guessing but I would have thought that the digital output from the Blu 2 would be vastly superior to that from a $149 device. I doubt that @Rob Watts short changed the digital output of the Blu 2 just for the sake of spending an extra $100 if it was needed.

 

[dmance]

@Triode User
BLU2 owners are spending $$ on the digital link cables because they hear a difference ...since the metal-to-metal cable contact transfers some of the analog noise from the big FPGA/PSU in the blu2 to Dave and affects the sound. I know, stupid that this problem exists ...should have been engineered out by @Rob Watts ...who was going to do a cable test himself and post results.

 

[Rob Watts]

Yes mia culpa - the BNC cable Blu Dave listening tests have been stuck in my to do list for the last 3 months. Frankly, doing rigorously controlled AB tests on very tiny differences is very time consuming and hard.

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 http://cpc.farnell.com/pro-signal/psg00541/bnc-plug-to-plug-1m/dp/AV14130
2M gold BNC http://cpc.farnell.com/pro-signal/psg00541/bnc-plug-to-plug-1m/dp/AV14131
5M BNC http://cpc.farnell.com/pro-signal/psg00541/bnc-plug-to-plug-1m/dp/AV14118

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 http://cpc.farnell.com/wurth-elektronik/74271111s/ferrite-core-split-5mm-320-ohm/dp/FT01652
Ferrite clamp, 7.5mm http://cpc.farnell.com/wurth-elektronik/74271111s/ferrite-core-split-5mm-320-ohm/dp/FT01655

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:

http://uk.farnell.com/wurth-elektronik/74271131s/ferrite-core-split-7-5mm-246ohm/dp/2082472

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.

Rob

 

[Triode User]

Yes mia culpa - the BNC cable Blu Dave listening tests have been stuck in my to do list for the last 3 months. Frankly, doing rigorously controlled AB tests on very tiny differences is very time consuming and hard.

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 http://cpc.farnell.com/pro-signal/psg00541/bnc-plug-to-plug-1m/dp/AV14130
2M gold BNC http://cpc.farnell.com/pro-signal/psg00541/bnc-plug-to-plug-1m/dp/AV14131
5M BNC http://cpc.farnell.com/pro-signal/psg00541/bnc-plug-to-plug-1m/dp/AV14118

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 http://cpc.farnell.com/wurth-elektronik/74271111s/ferrite-core-split-5mm-320-ohm/dp/FT01652
Ferrite clamp, 7.5mm http://cpc.farnell.com/wurth-elektronik/74271111s/ferrite-core-split-5mm-320-ohm/dp/FT01655

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:

http://uk.farnell.com/wurth-elektronik/74271131s/ferrite-core-split-7-5mm-246ohm/dp/2082472

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.

Rob

Rob,

Thank you for this detailed report and thank you for the time taken researching this. What you say makes so much sense (a breath of fresh air even) and so much more sense than exotic (and pricey) cables. I have ordered a bunch of the 7.5mm Ferrite cores from Farnell . . . . . . . . .

I also suspect that if power cables make any difference then the exotic ones can also be done away with and Ferrite cores might also help there. It's a big if though on the power chords. I have not noticed any exotic power chords at any Chord demo and maybe one day you will give the benefit of your thoughts there?

Nick

 

[Rob Watts]

With the mains with Dave I have a lot of RF filters - an initial input filter, filters in the SMPS, incoming PSU input filter (ferrite beads and big inductors), then distributed RF filters throughout the circuitry, plus extensive and multiple regulation.

With that in mind, I have just tried one of the 7.5 mm ferrites on the mains cable - and I can't be certain it's better as I was struggling to hear any consistent change. But on the BNC you could hear it instantly...

 

[Triode User]

With the mains with Dave I have a lot of RF filters - an initial input filter, filters in the SMPS, incoming PSU input filter (ferrite beads and big inductors), then distributed RF filters throughout the circuitry, plus extensive and multiple regulation.

With that in mind, I have just tried one of the 7.5 mm ferrites on the mains cable - and I can't be certain it's better as I was struggling to hear any consistent change. But on the BNC you could hear it instantly...

Rob, thanks. With that amount of filtering already on the Dave mains input it is probably unlikely that any additional will be needed as witnessed by your quich test but I have ordered a few more Ferrites than actually needed so I can try them elsewhere.

 

[Paul Bjernklo]

With the mains with Dave I have a lot of RF filters - an initial input filter, filters in the SMPS, incoming PSU input filter (ferrite beads and big inductors), then distributed RF filters throughout the circuitry, plus extensive and multiple regulation.

With that in mind, I have just tried one of the 7.5 mm ferrites on the mains cable - and I can't be certain it's better as I was struggling to hear any consistent change. But on the BNC you could hear it instantly...

Hi Rob: It would also be interesting when you have time if you can please advise if worthwhile to put ferrite cores on other cables such as USB and speaker cables. And also what speaker cables you use as I see that you are happy with low cost quality cables, but I have read that speaker cables affects sound the most. Thank you. Paul

 

[Rob Watts]

Hi Rob: It would also be interesting when you have time if you can please advise if worthwhile to put ferrite cores on other cables such as USB and speaker cables. And also what speaker cables you use as I see that you are happy with low cost quality cables, but I have read that speaker cables affects sound the most. Thank you. Paul

No unfortunately, dielectric, copper quality, solid core/stranding all make huge differences for analogue interconnects and speaker cables. My speaker cables are something I made; 8 cores per side of solid core 0.6mm individually PTFE insulated twisted together in bundles of 4, then 4 together. Then heat treated and annealed. And yes I had inserted ferrite cores on each end before soldering the 4mm connectors. The USB won't affect Blu as its before the BNC galvanic isolation; and I went through two prototypes to radically improve the BNC transmission sound quality. But the issue we have here is signal correlated RF noise from the actual BNC data corrupting Dave's ground plane, not Blu side noise getting through.