[jelt2359]

Here's more information regarding Blu Mk2 that may be helpful for some to know.  

Blu Mk2 will have both a USB and BNC/SPDIF input.  I was afraid USB would be replacing BNC/SPDIF and this will not be the case.  While I'm not sure I would use the BNC/SPDIF input, I believe it's good to have options and the more digital inputs, the better.

Neither the USB nor the BNC/SPDIF input will be galvanically isolated.  Rob has stated that this is because the DX outputs will already be galvanically isolated and there's no need to have them at the inputs also.  What this means is that only when paired with DAVE will Blu Mk2 (or M-scaler) offer galvanic isolation since only DAVE has DX connections.  Perhaps, another reason to buy the DAVE instead of Hugo2 (or any other DAC) for those interested in an M-scaler.

Thanks. Will the aes in still be available? And does this mean the blu2 will use the dx outputs as inputs?

 

[romaz]

Thanks. Will the aes in still be available? And does this mean the blu2 will use the dx outputs as inputs?

As an input, AES was never available.  As far as I'm aware, DX in Blu2 are outputs only.  In addition to the dual DX outputs, I believe AES, BNC/SPDIF and Toslink are all still available as outputs.

 

[romaz]

  Now a conventional interpolation filter (and MQA) is about 6 to 8 bits accurate for the interpolated samples with transients...But with the WTA M scaler we are guaranteed better than 16 bit accuracy for all signals...
 

 
This is helpful to know that MQA is only this good as there are many who continue to wonder why Chord DACs don't incorporate MQA decoders.  It's also telling that the DACs that benefit greatly from MQA are not even this good to begin with.
 

  ...this is why HD recordings do not guarantee great sound, as they are all a long way away from 16 bit performance.
 

 
Rob, can we expect that HD recordings will sound even better compared to 16/44 with M-scaler vs DAVE by itself?
 
 

  But I am not about to disappear for a year and design a 16M tap filter and then find out that 1M is enough - Davina will tell me exactly how much loss in sound quality we get in going from 768>48>768 using an M scaler; and I will publish these test recordings, so all can hear the losses that the decimation interpolation actually gives us.
 

 
This journey that you're on is quite exciting but to be honest, I hope Davina tells you that 1M is enough because I don't relish the idea of having to one day upgrade again to a 16M tap M-scaler housed in a giant Red Ref III chassis with a 160A PSU.

 

[jelt2359]

As an input, AES was never available.  As far as I'm aware, DX in Blu2 are outputs only.  In addition to the dual DX outputs, I believe AES, BNC/SPDIF and Toslink are all still available as outputs.

Gotcha. Sorry I meant dual dx outputs on dave- these are still output only? So the blu2 will connect to the dave via dual regular BNC?

I still don't get how you can have a digital output to an amp, though..

 

[Rob Watts]

Yes HD recordings benefit too; I am listening to Hildegard Von Bingen: Vox Cosmica (96 24b) at the moment - and I have never heard it sound so good. But what it does do is act as a giant leveler; the format is not important as the original recording is way more important; and I get a bigger improvement from RBCD with 1960's recordings, where the simple mic techniques, custom and simple optimized mixing really shines through.
 
Me too on 1M, I don't relish the design challenges of cascading multiple FPGA's together in an array. The power is less of a problem - each FPGA would have it's own regulator, so we are not talking about multiplying 10A@1V but 2A@5V. Even so a 16M scaler would be 32A at 5V!
 
Rob 

 

[Rob Watts]

 

As an input, AES was never available.  As far as I'm aware, DX in Blu2 are outputs only.  In addition to the dual DX outputs, I believe AES, BNC/SPDIF and Toslink are all still available as outputs.

Gotcha. Sorry I meant dual dx outputs on dave- these are still output only? So the blu2 will connect to the dave via dual regular BNC?

I still don't get how you can have a digital output to an amp, though..

The DX outputs will go to my DX input power amps - so these are specially designed digital input power amps that will decode the DX outputs from Dave.
 
I have started work on the next issue of PCB's for the first power amp.
 
The benefits of the power amp technology are that they are like Dave's output stage - one single feedback path from digital data to analogue outputs that will drive loudspeakers. The first model will be 20W, then multiple output powers to suit. The key to a single analogue stage is transparency - we only have 4 passive components in the direct signal path, one global feedback loop, and exceptionally low distortion, as the amp structure is a third order analogue noise shaper. The output stage is non-switching so timing recovery is set by the DAC. The early prototypes gave extraordinary depth and detail resolution, due to the simple analogue section.
 
Rob

 

[KMann]

 But I am not about to disappear for a year and design a 16M tap filter and then find out that 1M is enough - Davina will tell me exactly how much loss in sound quality we get in going from 768>48>768 using an M scaler; and I will publish these test recordings, so all can hear the losses that the decimation interpolation actually gives us..

Purely for the purpose of evalutaing how much difference  2M or 16M or even more taps would make, will it not be simpler  to compute the coeffecients using the WTA algorithm, and do the 16FS upsampling off-line on a computer using programming tools such as Matlab or Python, store the upsampled files and feed DAVE with 768Khz WTA upsampled version and listen for the difference?
 
Is the main challenge here is implementing the huge filter on FPGA, or  is it churning out optimal coeffecients for a given tap lenght that gives the most satisfying results?

 

[analogmusic]

I tried MQA software decoded from Tidal from my laptop into DAVE.
 
Initally was quite impressed, but then I realized (especially on Led Zeppelin's stairway to heaven, and how the levee breaks) something sounded off.
 
Then it hit me, the transients are too soft, as if the impact of the snare drum and guitar was diminished
 
I was not impressed with MQA...
 
How could Bob have unleashed MQA with Tidal, when it needed full hardware decoding to work properly?
 
Ho Hum
 
Maybe WTA filter doesn't work 100 % well when some other software has already changed the transients?
 
Maybe he was worried about Davina and needed to make a move fast?

 

[Kamil21]

The DX outputs will go to my DX input power amps - so these are specially designed digital input power amps that will decode the DX outputs from Dave.

I have started work on the next issue of PCB's for the first power amp.

The benefits of the power amp technology are that they are like Dave's output stage - one single feedback path from digital data to analogue outputs that will drive loudspeakers. The first model will be 20W, then multiple output powers to suit. The key to a single analogue stage is transparency - we only have 4 passive components in the direct signal path, one global feedback loop, and exceptionally low distortion, as the amp structure is a third order analogue noise shaper. The output stage is non-switching so timing recovery is set by the DAC. The early prototypes gave extraordinary depth and detail resolution, due to the simple analogue section.

Rob

Can't wait

 

[EVOLVIST]

@Rob Watts

Two questions:

1.) If you had a family member on the Watts side (let's say his name is David), who was waffling back and forth on whether to buy the Blu2 in March or wait for the Davina later on, what would you tell David would be the benefit of owning one or the other if he was streaming music into his DAVE? Any bells and whistles, besides the ADC in the Davina that would benefit his listening experience?

2.) Do, or did, you ever have a family member named David Watts?

 

[hibo2]

I've been reading the Dave posts prior to and after deciding to purchase a Dave.  They have been very informative and helped with the decision. I particularly appreciate the input from the Chord team giving an insight into the technicalities of Dave and the future improvements with new Chord products.  I took a look at their website to better understand  the benefits of the M scaler, part of the upcoming Blue2.  Among the photos displayed, one shows a stack with Blue2 above Dave in the fancy cradles.  Although sonically, Dave has been very satisfying, I have been critical of the aesthetics.  I have over time, come to overlook its eccentricities.  However,
the photo of Blue2 combined with Dave shows to me an almost complete lack of consistency of design among the various products.  Beyond the sharing of the basic case design; controls, display and decoration are all over the place and look a mess.  Possibly Chord originally intended Dave to be a stand alone product for headfi use.  Now that there is a clear intention that Dave will have dedicated amps and ways to integrate the M scaler tech, I really hope Chord take some time to design boxes that complement each other in a consistent, coherent and practical way so that owners will be proud to have them on display.

 

[analogmusic]

For me Davina is more interesting, as it allows recording of my Vinyl collection, just more features....
 
Who knows though, maybe Blu2 will finally allow me to pack up the Vinyl's and leave them to my Daughter for her to discover.
 
I am a fan of rock music and Bon Jovi is releasing his entire back catalogue on Vinyl set ,cost around 500 dollars.
 
Now I hope some of these are remastered from the original analog tapes, which analog masters used all the way to Vinyl.
 
if some of this has been recorded to a hi-def master, not sure it is worth it.
 
When comparing the Vinyl of the latest album, I wasn't that impressed, that is what Rob Watts said about hi-def recording, not really that much of an improvement compared to 44.1/16....

 

[Rob Watts]

@Rob Watts

Two questions:

1.) If you had a family member on the Watts side (let's say his name is David), who was waffling back and forth on whether to buy the Blu2 in March or wait for the Davina later on, what would you tell David would be the benefit of owning one or the other if he was streaming music into his DAVE? Any bells and whistles, besides the ADC in the Davina that would benefit his listening experience?

2.) Do, or did, you ever have a family member named David Watts?

The only thing that Davina will do (in digital mode) that Blu can't is sample rate convert from 768k to 44.1k (say).
 
Yes my Dad is David - my second name is David - John Franks brother is David...

 

[Mojo ideas]

This probably will never happen since Hugo2 is meant to be portable and galvanic isolation would eat up battery life.

Yes you are correct in that, but it's the supplied power over the USB coming from the source that would be the issue especially from phone's. It's their battery playing time that would suffer
Galvanic isolation is only really necessary with very old, electrically noisy PC's and laptops. This was because they had relatively primitive switching power supplies. These were Operating at relatively low frequencies This area of technology has been going through a revolution over the last six or seven years with vast improvements occurring. There were many more old source products around a few years ago. Modern laptop, pads and PCs just don't have the levels of ground modulation that would cause problems these days and phone's have virtually none at all so because Robs DAC technology is immuned also to Incoming jitter we felt it was not necessary to include galvanic isolation into Hugo2

 

[lovethatsound]

I've been reading the Dave posts prior to and after deciding to purchase a Dave.  They have been very informative and helped with the decision. I particularly appreciate the input from the Chord team giving an insight into the technicalities of Dave and the future improvements with new Chord products.  I took a look at their website to better understand  the benefits of the M scaler, part of the upcoming Blue2.  Among the photos displayed, one shows a stack with Blue2 above Dave in the fancy cradles.  Although sonically, Dave has been very satisfying, I have been critical of the aesthetics.  I have over time, come to overlook its eccentricities.  However,
the photo of Blue2 combined with Dave shows to me an almost complete lack of consistency of design among the various products.  Beyond the sharing of the basic case design; controls, display and decoration are all over the place and look a mess.  Possibly Chord originally intended Dave to be a stand alone product for headfi use.  Now that there is a clear intention that Dave will have dedicated amps and ways to integrate the M scaler tech, I really hope Chord take some time to design boxes that complement each other in a consistent, coherent and practical way so that owners will be proud to have them on display.

As far as aesthetics are concerned,i think that's down to the individual who's looking.I personal like the way dave and the blu look,most hifi equipment just look like boxes to me,so for me it,makes a refreshing change to see something look a little different.As they say Beauty is in the EYE of the Beholder☺