[dmance]

This is not correct. Bits are only perfect when there is error correction.

This does not happen with USB audio. Please do some research and you will see this is the case.

.

analogmusic ...don't confuse the theoretical limits with the practical. What you (and many other audiophiles) grossly misconstrue is what we hear with our ears with dropped bits and packets. I will be now plain and simple:

• This is the sound of dropped packets or digital artifacts: POP, CHIRP, CLACK, BRRP. "The raaaainnn innn sp______ain faaallsssss"
• This is the sound of RF noise from the source (PC, Mac, Streamer) travelling along the USB pins to the DAC: "Not musical, muddy mids, no energy in the bass, constricted soundstage, less PRat". And this is through the entire track - and all tracks!

Are you saying that a bit error here and there is responsible for tainting the entire track? So, for the love of Mike(Rob ), please use your ears and whats between them to realize the obvious: that when you spend money on USB cables or filters or streamers or whatever - you may think you are fixing a digital issue but really you are fixing an analog problem.

Sure maybe, just maybe, a circa-2002 PC dropped a few packets of USB audio or maybe your fridge compressor kicking in knocks a bit loose from a lousy cable. USB audio is error prone that way (as per your article and Mr. Rankin) - but as Rob Watts says ...virtually all modern USB Audio 2.0 async transmission is 'good enough' to get 99.99999% of the bits across with no errors (or else DSD over DOP would fail).

Dan

 

[raypin]

mm...placed an order with my dealer here. ETA 3 to 4 months. Ordered it to see if my HE 1 will scale up with better equipment (Chord Dave + M Scaler).

 

[Sonic77]

So this usb situation is begging the question what can deliver bit perfect signal and why isn't anyone making that? If usb is such a bad standard, come up with something else? My Mirus dac has a sd card reader built in, hows that for a solution (I know the file size is small)? Any others, or can usb be fixed enough to work?

 

[Triode User]

So this usb situation is begging the question what can deliver bit perfect signal and why isn't anyone making that? If usb is such a bad standard, come up with something else? My Mirus dac has a sd card reader built in, hows that for a solution? Any others, or can usb be fixed enough to work?

I thought what is being said is that the issue is not perfect bit signals because by and large perfect bit signals are being transmitted and received. The issue seems to being said to be RF noise. Although I would agree that probably isn't rocket science to get rid of RF noise or to stop it from getting into the cable (nor therefore is there a need to spend silly amounts on the cable).

 

[Malcyg]

We had friends round last night and, after dinner, my friend and I retired to the lounge for a drink whilst the girls did what girls do. Anyway, he has a very nice (read expensive) system himself, but he is a staunch vinyl man and always has been. We got talking about my system and, naturally, he wanted to hear it. So I played him a file through Dave alone and he was quite impressed.

He laughed and said he could be tempted to get a CD player himself given how good it sounded. I then played a CD through the BluDave combination. His expression was quite amusing and he seemed quite perplexed. Then he told me to play a couple of CD's of albums that he was very familiar with. After that, he stated that it sounded at least as good as his vinyl and probably better. That is something coming from him, I can tell you.

Discussing it with the dealer that sold me the Blu II and the Dave, he said that the Blu Dave combo is better than any turntable that they have had through their doors, so quite high praise indeed. I just wish more of them were shipping out so others can experience and feedback on this thing.

 

[Sonic77]

I thought what is being said is that the issue is not perfect bit signals because by and large perfect bit signals are being transmitted and received. The issue seems to being said to be RF noise. Although I would agree that probably isn't rocket science to get rid of RF noise or to stop it from getting into the cable (nor therefore is there a need to spend silly amounts on the cable).

My bad, I am sleepy

 

[esimms86]

fyi, my dealer in the US tells me that my Blu2 is expected to be shipped to me in 2 weeks. He included the email from Bluebird Music in his email message to me.

 

[analogmusic]

analogmusic ...don't confuse the theoretical limits with the practical. What you (and many other audiophiles) grossly misconstrue is what we hear with our ears with dropped bits and packets. I will be now plain and simple:

• This is the sound of dropped packets or digital artifacts: POP, CHIRP, CLACK, BRRP. "The raaaainnn innn sp______ain faaallsssss"
• This is the sound of RF noise from the source (PC, Mac, Streamer) travelling along the USB pins to the DAC: "Not musical, muddy mids, no energy in the bass, constricted soundstage, less PRat". And this is through the entire track - and all tracks!

Are you saying that a bit error here and there is responsible for tainting the entire track? So, for the love of Mike(Rob ), please use your ears and whats between them to realize the obvious: that when you spend money on USB cables or filters or streamers or whatever - you may think you are fixing a digital issue but really you are fixing an analog problem.

Sure maybe, just maybe, a circa-2002 PC dropped a few packets of USB audio or maybe your fridge compressor kicking in knocks a bit loose from a lousy cable. USB audio is error prone that way (as per your article and Mr. Rankin) - but as Rob Watts says ...virtually all modern USB Audio 2.0 async transmission is 'good enough' to get 99.99999% of the bits across with no errors (or else DSD over DOP would fail).

Dan

fair enough, I don't really want to spend 1000 dollars on a USB cable myself. I would much rather use that money towards paying for a Blu2.

Not sure what DSD over DOP means, but will try it with my Dave with both cables.

I'm quite happy with the Vertere USB cables, not sure why or how (don't understand the RF aspect of cables as I am no engineer), but there is a difference from the admittedly very cheap and maybe not well made USB cables that are used to charge mobile phones I had been using previously.

I do use Naim amplifiers, and from the little I know about them, I think these are very old designs, not sure if they were designed to cope with the high levels of RF in the environment today. I mean these have very good cases made of aluminium, but some of the interconnect cables used by Naim are not shielded. When replaced by shielded ones, it has been reported that there is a jump in performance.

Naim amps also were designed around a particular speaker cable made by Naim called A5, and this is not shielded (against RF). Only Teflon insulation.

The new hi-end cables that Naim charge exorbitant money for called Superlumina, well these are shielded against RF. But I'm not happy to pay that much for cables.

Waiting for Rob's digital amps.............

 

[x RELIC x]

Not sure what DSD over DOP means, but will try it with my Dave.

DoP DSD means DSD over PCM, not to be confused with DSD converted to PCM. Basically because there is no standard for DSD transmition on a USB connection without drivers (like PCM audio) the DSD file is wrapped in a PCM container that fools the USB interface in to transmitting the file as audio data. When a DoP capable DAC see's the DoP flag it grabs the DSD file and plays it identically to the original DSD file, because it is identical. It's essentially a fix for the Wild West of USB DSD transmition without drivers.

http://dsd-guide.com/dop-open-standard#.WVcJULETGfA

The USB Audio specification 2.0 defines multiple formats for audio of which standard PCM is only one. A general “raw data” format was also defined that can be used for any kind of data including audio, but unfortunately, no specific format was defined for DSD and with the ongoing proliferation of USB converters in the current market it appears that the opportunity for the official USB specification to adopt a single common method of transferring DSD audio via USB is slowly disappearing. This is an attempt of uniting as many manufacturers as possible and jointly defining a method for transferring DSD via USB. While this method is mainly targeted for USB links it is general enough to be applied to other PCM based links such as Firewire, AES/EBU, S/PDIF etc.

https://www.dcsltd.co.uk/support/what-is-dop-dsd-over-pcm/

FAQ: What is DoP (DSD over PCM)?
The original idea for DoP was invented by dCS in 2011. It involves taking groups of 16 adjacent 1-bit samples from a DSD stream and packing them into the lower 16 bits of a 24/176.4 data stream. Data from the other channel of the stereo pair is packed the same way. A specific marker code in the top 8 bits identifies the data stream as DoP, rather than PCM. The resulting DoP stream can be transmitted through existing 24/192-capable USB, AES, Dual AES or SPDIF interfaces to a DoP-compatible DAC, which reassembles the original stereo DSD data stream COMPLETELY UNCHANGED.

If something goes wrong and the data stream is decoded as PCM, the output will be low-level noise with faint music in the back ground, so it fails safely. This can happen if the computer erases the marker code by applying a volume adjustment.

 

[Kamil21]

This new review of the dCS Network Bridge was conducted with the Dave DAC.

It claims that it betters the available standard CD transports. I wonder how it might improve upon the Blu2 transport?

http://highfidelity.pl/@main-759&lang=en

 

[Malcyg]

This new review of the dCS Network Bridge was conducted with the Dave DAC.

It claims that it betters the available standard CD transports. I wonder how it might improve upon the Blu2 transport?

http://highfidelity.pl/@main-759&lang=en

Yes, I've been looking at the Bridge myself with a view to trying it to see if it improves upon mRendu in my system. I didn't draw the same conclusion as you from the article though as my reading was that he still favoured CD's. It wasn't clear to determine really, but from this quote 'Also, in my opinion, it's still not the same level that physical media have to offer. This stage is still ahead of us.' He is using a BNC adapter to connect to his Dave which, in my experience, provides the worst results that Dave is capable of.

There is a new Ultra version of mRendu coming out as well as SoTM Ultra and a new Aries G2, so plenty of action coming up in this area. This bridge and the Ultra Rendu are the two that I'm most interested in, but only given that the Bridge will eventually be able to output via USB through a firmware update.

 

[Kamil21]

Yes, I've been looking at the Bridge myself with a view to trying it to see if it improves upon mRendu in my system. I didn't draw the same conclusion as you from the article though as my reading was that he still favoured CD's. It wasn't clear to determine really, but from this quote 'Also, in my opinion, it's still not the same level that physical media have to offer. This stage is still ahead of us.' He is using a BNC adapter to connect to his Dave which, in my experience, provides the worst results that Dave is capable of.

There is a new Ultra version of mRendu coming out as well as SoTM Ultra and a new Aries G2, so plenty of action coming up in this area. This bridge and the Ultra Rendu are the two that I'm most interested in, but only given that the Bridge will eventually be able to output via USB through a firmware update.

You could be right. I Re-read the article and found this:

"This is something that no audio file player I know - aside from workstations in recording and mastering studios - can do as well as physical media, including CDs. ".

So it seems this author prefers CD's over the Network Bridge.

Of note is the photo of the Blu2 in the background, although there is no mention of this in the article. I would hope that a comparison is in the works.

 

[Jawed]

Why would workstations in recording and mastering studios sound better than everything available to consumers? Do they have alien technology?

Now playing: Stina Nordenstam - Sharon & Hope

 

[seeteeyou]

I wish that we're living in an ideal world where everything is right as rain once we're going for asynchronous USB with nothing but 0s with 1s.

In reality we're actually looking at a different picture:

http://www.whatsbestforum.com/showt...ound-Different&p=448050&viewfull=1#post448050

The issue isn't the ones & zeroes - they are delivered as expected. What seems to be different between cables is the signal waveform of the digital signal arriving at the receiver.
There are a number of ways this signal waveform can be different but the USB standard specifies a range of acceptable distortion in this waveform - basically the USB standard defines a 'safe' level of distortion in the signal waveform that will avoid bit errors i.e. the ones & zeroes will be correctly received by the receiver.

Now a USB cable doesn't just carry the USB signal on two wires within the cable - it also has 2 additional wires in the cable, ground & 5V power & finally has a shield. These two wires & shield further complicate matters when it comes to signal integrity. All can carry noise between the PC & the USB receiving device - noise is just another signal waveform distortion as is jitter - neither of these issues affect the delivery of the digital bits (once within the acceptable range of the USB standard).

In my experience when there are changes in these factors it can often have an audible effect. Cables can change the noise spectra on the cable, on the cable shield, on the signal wires, on the ground & power wires - all/some of which can have audible effects.

I haven't listened to expensive USB cables but have used a cable which is made to suppress EMI noise - http://kgs-ind.com/wp-content/uploads/products/pdf/LNC-Noise-Suppression-USB20-Cable.pdf
This cable is not an audiophile offering - it is made for use in airlines, I believe & consists of a flexible ferrite compound fully covering surrounding the 4 USB wires. For those addicted to measurements, look at the noise measurements on the linked page - it shows the reduction in noise in the frequency range 50MHz to 1,000MHz. Now how could reduction in noise in these frequencies have audible effects in the audible range? Objectivists need to be inquisitive enough to investigate but they don't have the necessary motivated or skills, it would appear

This was noticeably quieter than my other USB cables but had the side effect of somewhat audibly softening high frequencies. This is not that surprising, as those who have tried ferrous rigs on USB will no doubt attest to.

https://www.computeraudiophile.com/...rail-of-computer-audio/?page=2#comment-645112

USB signal Integrity contains a number of factors; jitter, signal rise-time, its level and balance between the two wires are other factors and excessive ripple from reflection within the cable is yet another factor to impact signal integrity, potentially enough for data corruption (which is NOT corrected in isochronous streaming mode).

Impacts on signal integrity are produced by among others (an exhaustive list would be challenging) by cable impedance mismatch, impedance mismatch at connectors, electrical fields from nearby cables and transmitters and not the least isolation devices.

https://www.computeraudiophile.com/...rail-of-computer-audio/?page=6#comment-655946

There is some inconsistency in the use of the term 'asynchronous'.

Asynchronous USB (audio) is a marketing term that was coined by a company that introduced the first practical implementation of the asynchronous mode of USB audio class and has gone into widespread use, though strictly speaking the terminology is somewhat questionable.

For USB A/V class devices the streaming is ALWAYS isochronous, no matter if they are called asynchronous or adaptive or synchronous.

We discussed this in our paper over at Audiostream:

http://www.audiostream.com/content/usb-audio-gremlins-exposed-beyond-1s-and-0s-ifi-audio

Almost all ethernet based protocols for audio distribution are also isochronous. For ethernet, "asynchronous" is a formal term implying that data packets may be sent in nonlinear order, at no fixed timing etc.

To illustrate this better, when playing a music track from a network disk share, you are using asynchronous ethernet, the player device must handle buffering of data to make sure there is no stuttering due to delayed data, as there is no guaranteed stream bandwidth, however data corruption will result in data re-transmission so the music track will always be bit-perfect.

When playing a music track from any "server" device that uses isochronous ethernet streaming, it is guaranteed that the bandwidth required for the stream is reserved (though network contention/collision/interruption may still occur). However if any data packet is corrupted error concealment must be used as there is no way to recover corrupt data. So

https://www.computeraudiophile.com/...tec-ref-10-masterclock/?page=9#comment-690899

There is a bit of a gotcha with 75 ohm BNC cables. MANY of the cables available "out there" use 75 ohm cable but use 50 ohm BNC plugs!

Several years ago I ordered 12 such cables from different companies and only 4 of them had actual 75 ohm plugs. They all had 75 ohm cable, but only 4 got the right connector.

Several of these were well known cable assemblers and they even got it wrong.

John S.

Even coaxial cables that are supposedly 75Ω in theory turned out to be something else in practice. Plenty of things might sound good on paper but eventually we'll realize that many of us might be idealizing how "perfect" something is.

However, RAVENNA could very well have the potential to be an exception and hopefully we'll see that Merging ZMan to be combined with M-Scaler in the future:

http://www.merging.com/news/news-stories/merging-innovation-at-high-end-munich-2017

Besides the manufactured products, Merging will introduce ZMan, a new compact and powerful RAVENNA circuit board which will be offered to OEM partners, bringing the advantages of a networked solution to audio components as diverse as loudspeakers, DACs and server/streamers. In addition to RAVENNA, this board will allow for a whole range of other capabilities like Roon Ready support, streaming services and DSP processing for advanced formats decoding or room correction for example. This OEM solution as well as associated development tools will be on display in the RAVENNA Corner and engineers will be available for answering technical questions.

https://www.computeraudiophile.com/...anned-ultimate-audio-pc-build/#comment-690274

In my experience, the PC noise or nastiness or whatever, has no effect on the audio when using Ravenna. I recently built a high end custom PC similar to this build, for someone who wanted to use Roon with HQP (CUDA offload) and tens of terabytes of music.

The PC was fairly quiet, but I'm sure electrically is wasn't the quietest. However, using Ethernet / Ravenna, I've found no difference to the audio quality based on this noise.

I know others have had just the opposite experience and I don't discount their opinions or results at all. Just sharing my experience.

 

[Currawong]

You could be right. I Re-read the article and found this:

"This is something that no audio file player I know - aside from workstations in recording and mastering studios - can do as well as physical media, including CDs. ".

So it seems this author prefers CD's over the Network Bridge.

Of note is the photo of the Blu2 in the background, although there is no mention of this in the article. I would hope that a comparison is in the works.

Nobody who knows how a CD actually works would say that IMO. At a guess it's probably that physical CD players don't have a whole bunch of circuits that dump noise into the electronics compared to USB and network gear.