[Rob Watts]

Is Blu 2 the end though? I doubt it.

If DAVE's output stage can resolve the performance of a noise shaper with 350dB of resolution, then Blu 2 seems to be far short.

Now playing: Stina Nordenstam - Fireworks

You are mixing up differing errors; there is the small signal non-linearity error, which the 350 dB figure refers too, and the transient timing error, for which the Blu 2 is trying to reduce - that's what the 1M taps are for.

The small signal non-linearity error for Blu 2 actually exceeds Dave's performance:

The noise floor up to 16 kHz comes from the test tone.

As to the transient timing error, then I do not know how much further one needs to improve it; all I know is that against the ideal sinc function (which will perfectly reconstruct the bandwidth limited signal inside the ADC before sampling) the 1M taps WTA exceeds 16 bit accuracy. Whether our hearing needs more than this remains to be seen; Davina will tell me how far short we are from perfectly reconstructing the original un-sampled signal from the subjective POV.

Interesting times ahead.

Rob

 

[DaveRedRef-III]

i think if there is any bottleneck left after Dave + Blu MkII it is unlikely to be much and audiophiles would be better off focussing on their power amps, room acoustic treatment and speakers first. The sound compromises there are likely to be significant in most cases by comparison

 

[Jawed]

You are mixing up differing errors; there is the small signal non-linearity error, which the 350 dB figure refers too, and the transient timing error, for which the Blu 2 is trying to reduce - that's what the 1M taps are for.

I connected the two because you weren't expecting Blu 2 to improve depth perception, but for some reason it does. In the past it seemed like the noise shaper performance was at the root of depth perception.

In the past you've talked about improved timing perception enhancing perceived tonality and texture of instrumental sounds. I guess that the way that tonality of a sound changes in the course of its envelope is a mechanism for depth perception. Which makes me guess that timing performance is linked to depth perception because it affects the tonal relationships in a sound over time.

A million taps will produce different results depending on the upsample rate: 16FS versus, say, 256FS. Notionally the latter would have more timing error when trying to recover the original band-limited 44100Hz sampled audio before sampling - because each final sample at 256FS is derived from fewer of the 44100Hz samples - it's a worse approximation of the ideal sinc function. Yet we already know that from Hugo to DAVE/Hugo 2, increasing the first stage WTA from 8FS to 16FS is a big improvement. Despite the tap count at the higher upsample rate being unchanged.

That seems to imply that the sample rate produced by the first WTA stage is more important than the tap count. So I wonder what happens if the first WTA stage is set to 256FS. And what tap count does it require to exceed the performance of a million taps at 16FS.

Now playing: Low - Slide

 

[Rob Watts]

Yes it is certainly very odd that the M scaler opens up the sound-stage in a way that I have never seen before with WTA filters. Depth perception has always, in the past, been explainable in terms of small signal amplitude non-linearity and that is still my thinking; I suspect that the filter time period, which depends only on tap length and oversampling rate, is somehow affecting small signal amplitude. I have some experiments in mind to investigate this.

 

[Sonic77]

Blue Bird audio has not responded to my email about delivery dates. Has anyone else gotten any North American delivery dates? June is half over.

 

[Malcyg]

Chord website said that Blu II was shipping 6 weeks ago, but nobody round here seems to have had a delivery. This does seem to be the pattern with Chord releases.

 

[birdlandbill]

Blue Bird audio has not responded to my email about delivery dates. Has anyone else gotten any North American delivery dates? June is half over.

Received an e-mail from Bluebird Music June 7 re: arrival time

"Sorry but it is unknown at this time, we will let the dealer know when we can."

Since that time someone may have received one in North America. Would be encouraging to hear from the lucky ones.

 

[adyc]

Received an e-mail from Bluebird Music June 7 re: arrival time

"Sorry but it is unknown at this time, we will let the dealer know when we can."

Since that time someone may have received one in North America. Would be encouraging to hear from the lucky ones.

My dealer told me that they don't know the arrival time. Do they discover last minute bugs or hit some kind of production troubles?

 

[ray-dude]

My understanding (indirect, so may be wrong) is the Bluebird skips initial shipments of Chord kit, waiting for things to settle out

 

[onsionsi]

I would like to ask who's did this before, can i take my Dave in an Aeroplane using a backpack or this is not allowed in Flight regulation.

 

[HiResGeorge]

My dealer told me that they don't know the arrival time. Do they discover last minute bugs or hit some kind of production troubles?

I had one here in Scotland 2 weeks ago but I sent it back for investigation as it had trouble playing a cd from 78 minutes in length. It may indeed just be a limitation of the 74 minute red-book standard though, as the cd transport is the legendary Philips CD-pro 2.
However, partnered with the DAVE in dual BNC and upsampled to 705.6, it is wonderfully superb and I never thought it would be possible to hear such a full, vibrant sound stage from a regular 16 bit source !! If the playing time can be tweaked to a maximum of 79.55 mins, then this would be the pinnacle of listening enjoyment.

 

[Sonic77]

Still no updates or response from Blue Bird Audio or Chord.

 

[Sonic77]

http://www.bluebirdmusic.com/news/latest-news-for-poly-blu-mkii-and-hugo2.html

Updates.

 

[Malcyg]

Quite unexpectedly, my second Blu II unit has arrived. Like Dave, I'm sure it will sound better in silver!

It will be interesting to hear the Blu Dave combination again since I have got quite used to standalone Dave now and have been happy with it.

 

[rrolls]

A friend and I have got a Blue 2. We listened to it in our environment. Both of us bought it when we had listened to music for just a few minutes.
It was his turn, because I prefer silver, and the test unit is black. Now I must wait. Nevertheless, we have a problem, regarding to the BNC cables.
When I first connected the Blue to the DAVE, I took our high-quality silver cables from Audiosensibility, mine is 1.5m and his is 1m, even if I had read, that the cables
should be of equal length. The short ones supplied look quite cheap, so I thought quality is more important than length, and I was completely wrong.
The sound was harsh, more like a CD player from the past. I switched cables and the journey to HIFI heaven started.
The problem is now, that these short cables are about 50cm.
There is common sense that the rule the shorter the better does not apply to digital cables, they should be longer, at least 1m, because of reflection.
So, I have questions:
- Is the length of the cables unimportant in this special dual application?
- Is the quality of the cables unimportant in this application, or would it still be an advantage to buy "better" cables.
I remember well, that I used a silver one when I had the DAVE on trial, but the cable from the Company above was much better, and silver as well.
My friend is going to drill a hole into one board of his rack to save length, but my rack is made from Plexi, and I have to use longer cables.

Both of us would appreciate the help of Mr. Watts. Thank you.