Jump to content
IGNORED

USB audio transmission isn’t bit true


Recommended Posts

11 hours ago, beerandmusic said:

you stated there are many dacs that do this...i wasn't asking which are inexpensive...i just asked of the dacs that you are aware of, which is the least expensive one that you are familiar with?

I believe the schiit dacs do this with their "unison" usb, but Miska said the bifrost didn't measure well, so am looking at other options, and would prefer DSD if possible, but not necessary.

Even of the "many" you suggest, none are inexpensive, I still want to know which is the least expensive one you are familiar with as a "starting point"

 

I can perhaps provide an example (not exactly "cheap" of course)

 

The Soekris DAC1541 User Manual states "The dac1541 R-2R DAC circuit is fully isolated from the noisy computer USB interface and the SPDIF inputs are also all transformer isolated" (the also implying that the isolation of the USB init is also via transformer) and in fact on the board there are three little SMD PCB DA101MC transformers.

 

DO not be fooled by the DAC1421 measurements on ASR which are suspiciously off (and of course the folks there use them to conclude that the DAC1541must be crap) – on SBAF the DAC1541 was measured and showed quite good values. The sound is really great as well.

Link to comment
2 hours ago, mocenigo said:

 

I can perhaps provide an example (not exactly "cheap" of course)

 

The Soekris DAC1541 User Manual states "The dac1541 R-2R DAC circuit is fully isolated from the noisy computer USB interface and the SPDIF inputs are also all transformer isolated" (the also implying that the isolation of the USB init is also via transformer) and in fact on the board there are three little SMD PCB DA101MC transformers.

 

I think any new dac i buy will specifically market galvanic isolation, and if that isn't really necessary, then the topping d90 is looking better all the time...but i still don't think it will sound any better than just streaming with my marantz, as that has been my experience after trying about 15 different dacs.

Link to comment
10 hours ago, beerandmusic said:

I have yet to find one usb dac that sounds as good as other interfaces

The above suggests to me that your USB source is the problem, not the DACs you have tried.  If you are just plugging in a commercial computer to evaluate the DACs, that is a mistake:  The USB source matters, there is a reason that custom servers with dedicated USB output cards exist; there is a reason that Ethernet Renderers with carefully designed USB outputs exist.

 

Even something as simple and affordable as the Sonore microRendu has a much, much better USB output than any commercial computer.

 

Add Chord Qutest to your list of affordable DACs with an isolated USB input receiver.

 

BTW, measurements have shown for quite some time that the USB input on many DACs is at worst equal to the SPDIF input, and the USB input on many DACs often measures better than the SPDIF input-check out the jitter measurements of the different inputs done by John Atkinson over at stereophile.com.  Note that those measurements were mostly done with a MacBook Pro directly connected to the DAC, and even still, the USB input often performs better than the SPDIF inout.

SO/ROON/HQPe: DSD 512-Sonore opticalModuleDeluxe-Signature Rendu optical with Well Tempered Clock--DIY DSC-2 DAC with SC Pure Clock--DIY Purifi Amplifier-Focus Audio FS888 speakers-JL E 112 sub-Nordost Tyr USB, DIY EventHorizon AC cables, Iconoclast XLR & speaker cables, Synergistic Purple Fuses, Spacetime system clarifiers.  ISOAcoustics Oreas footers.                                                       

                                                                                           SONORE computer audio

Link to comment
10 hours ago, beerandmusic said:

.......and I have yet to find one usb dac that sounds as good as other interfaces. 

 

I would try a Schiit Yggdrasil with Unison USB input. According to the manufacturer Unison USB is the best interface of this DAC. But Source First does apply here as well and you need a good USB host. That is the reason they are developing their Unison USB output.

 

Matt

"I want to know why the musicians are on stage, not where". (John Farlowe)

 

Link to comment
7 hours ago, mocenigo said:

The Soekris DAC1541 User Manual states "The dac1541 R-2R DAC circuit is fully isolated from the noisy computer USB interface and the SPDIF inputs are also all transformer isolated" (the also implying that the isolation of the USB init is also via transformer) and in fact on the board there are three little SMD PCB DA101MC transformers.

 

That is not correct. The Murata transformers used in the Soekris DACs are for the three S/PDIF inputs (AES, BNC, RCA).  There appear to be standard digital isolator chips on the I2S (and clock in/out) lines after the XMOS processor.  And then some VERY long traces after those--past the power supply networks--to input portion of the DAC proper.

1846632566_Soekrisdac1541.thumb.jpg.e7677e0078a7723173b4b5830cc8c02e.jpg

Link to comment

 

2 hours ago, barrows said:

The above suggests to me that your USB source is the problem, not the DACs you have tried.  If you are just plugging in a commercial computer to evaluate the DACs, that is a mistake:  The USB source matters, there is a reason that custom servers with dedicated USB output cards exist; there is a reason that Ethernet Renderers with carefully designed USB outputs exist.

 

Even something as simple and affordable as the Sonore microRendu has a much, much better USB output than any commercial computer.

 

...

purpose built hardware solution matters... I started with and went back to a 2nd microRendu before I found a better solution. And unlike  the other solutions, the microRendus didn't require an expensive power supply to sound good. Great for the non hobbyist.

 

Many digital users aren't that different than vinyl users of the 80's who complained about audio quality but insisted that their Technics turntable couldn't be

the cause for the lack of dynamics and low bass in their playback.

Regards,

Dave

 

Audio system

Link to comment
2 hours ago, Superdad said:

 

That is not correct. The Murata transformers used in the Soekris DACs are for the three S/PDIF inputs (AES, BNC, RCA).  There appear to be standard digital isolator chips on the I2S (and clock in/out) lines after the XMOS processor.  And then some VERY long traces after those--past the power supply networks--to input portion of the DAC proper.

1846632566_Soekrisdac1541.thumb.jpg.e7677e0078a7723173b4b5830cc8c02e.jpg

 

Thank you for the correction.

 

Regarding the long tracks, well, I guess ut was a matter of choosing the lesser evil: transformers at the end, allowing these tracks to leak noise, or transformers at the beginning, allowing the tracks to get some noise injected by something else inside the device. Since Soren Kristensen believes in the low emission of the medical Meanwell switchers, I think he chose following that.

Link to comment
  • 7 months later...
On 6/11/2020 at 3:34 AM, Superdad said:

ZMAN OEM from Merging Technologies: AES67/Ravenna only.

 

Hi @Superdad

 

I remember early on , you said you had a Zman board in hand to evaluated

 

Without talking about any specific Uptone product, is the Zman board something you think you will use in the next year or 2?

 

Or you've lost interest in this particular board for the short term? Driver issues?

 

Link to comment
4 hours ago, asdf1000 said:

I remember early on , you said you had a Zman board in hand to evaluated

 

Without talking about any specific Uptone product, is the Zman board something you think you will use in the next year or 2?

 

Or you've lost interest in this particular board for the short term? Driver issues?

 

We have a signed developer NDA with Merging and we receive documents, updates, and pricing on their ZMAN OEM program, but we never ordered the dev boards as the project we had in mind for it is on hold.

 

I continue to maintain that acceptance and broad implementation of Ethernet (or other interface) as a DAC input standard is dependent upon freely available (if not free), well supported, multi-platform “virtual sound card” software and network discovery protocols, preferably integrated into application solutions people want to use.

 

Using the above criteria, one can understand why the long available DLNA/UPnP rarely gets much love, while the rather similar but tight integrated Roon RAAT protocol has emerged as the driving force behind recent-year’s popularity of Ethernet-input DACs and streamers.

 

I believe that the ZMAN module now includes code to support RAAT and be seen as a Roon-Ready endpoint. But for some reason ZMAN does not seem to have caught on with many consumer DAC manufacturers yet. Not sure why that is. Perhaps price. It is a much more advanced Ethernet>I2S solution than the popular Conversdigital MConnect, but a fair bit more complex to implement. Maybe that is why.

 

For greater context, see my post here:

 

Link to comment

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...