Jump to content
IGNORED

Best Audiophile USB Card ?


Recommended Posts

5 hours ago, matthias said:

 

There was no disclosure by Emile, he said it is an "industrial" one.

 

Matt

Renasus UPD720202 from the package and circuit's pin out.

 

The -711 variant is the -40 deg C temp range otherwise not sure what would attract the "industrial" commet if not this, there are only two variants.

 

 

OAudio Ltd.

OAudio Supreme - music server.

OAudio RealStream - digital audio components.

 

Link to comment
2 hours ago, wittao said:

Yes, we are using the same.

 

They are very nice looking boards in your pics. I had noticed the UPD's 😉 thanks for confirming. Looks like you are also using the 701s with ROM which is the way I went as well.

 

I have some 711s I might have a look at them again. My understanding was that they are for embedded use where BIOS writes the firmware blocks to the chipset at boot time. That "industrial" comment has me wondering if I missed a way to use these ?

 

 

OAudio Ltd.

OAudio Supreme - music server.

OAudio RealStream - digital audio components.

 

Link to comment
  • 2 weeks later...
  • 1 year later...

I am working on a new card at the moment (listening to it as I type) and plan to provide an update after posting here about my earlier USB RealStream card :D

 

Its been something of a mission, like many of us, I have always found USB to be "broken" to a greater or lesser extent for high end audio. I first started using and working with USB in 2007 and have been gritting my teeth listening to its digital signature stamped on music since then :(. The technical challenge of streaming over USB in really high fidelity systems is without question a many headed beast. Just look at threads here on Audiophilestyle and the countless threads elsewhere discussing what might be happening to fragile music streams as they are piped from server/streamer to DAC over USB. Finally eighteen months ago for me it had to be either fix it or look to other standards for an interface. An objective since then has been to create a genuinely transparent USB interface regardless of the work required. And, I think its finally done :o .

 

The card will be PCIe but unfortunately it has to function a part of a broader system with bespoke interfaces so it cannot be made generally available. Sorry. It will be a recognisable PCIE card though in a few months, so I will post some pictures here when its finished. I hope they will be of interest.

 

 

 

OAudio Ltd.

OAudio Supreme - music server.

OAudio RealStream - digital audio components.

 

Link to comment
  • 2 weeks later...
On 2/17/2023 at 12:20 PM, wittao said:

In addition about Crystec's 957 series oscillators: the theoretical parameters are ok and gives to the engineers important informations. Earlier (5-6 years ago) we used that Crystec oscillators in our USB/SPDIF converters 24 - 24.576 - 22.5792 MHz freqs and works well but unfortunately in the PCB the oscillators working different then alone connected to the measurement equipment...  -90dB@10Hz is a typical phase noise at that oscillators. We dropped them finally and started to develop our own oscillators. 

 

 

For an £10-20 part they offer amazing performance however all of the "Femto" clocks I have looked at are limited by their BOM costs and formfactor limitations.

 

Once you load their outputs they are unpredictable for high level audio use. Drive even a 50 ohm PCB trace (in fairness they are not really spec'd to do this) let alone coax and be prepared to see audio performance pulled all over the dial. Of course you can use them to drive high impedance loads over very short trace lengths but even here the outputs can struggle.

 

I have spent months and months understanding these problems and working out solutions. These devices fundamentally offer decent close in phase noise performance and excellent phase noise floor performance away from the carrier frequency. Here the above limitations are fixed but the solutions cost many 10s of times the cost of the "femto" clock itself. Well worth the effort though in terms of musical performance :).

        

OAudio Ltd.

OAudio Supreme - music server.

OAudio RealStream - digital audio components.

 

Link to comment
15 hours ago, Jarek_Jcat said:

This discussion is heading in a bit wrong direction, as clock phase noise, important of course but not the only aspect of good sounding clock. Same as noise of power supplies. If we compare Jcat Initio3 and Optimo3Duo, even thou they share same circuit design, have more or less same PCB and noise wise measure exactly the same, they do sound different and Optimo3Duo is significant upgrade over Initio3.

Same goes with clock. There are so many other aspects affecting it’s performance. From power supply and it’s distribution, buffering, signal distribution, output stage, PCB design and many more. Also removing oscillator from USB card and it’s power supply equation, affects SQ. All that matters and was addressed in Master OCXO module design, and is reason it looks quite complex. Master OCXO is step up in phase noise performance over oscillator used on Jcat USB card, but all in all from sound quality perspective it is much more complicated.

 

kind regards

 

Indeed, phase noise performance only counts when it is delivered directly onto the pin of the device you are driving. Not withstanding the oscillator's performance, implementation is everything.

 

I'm not sure that I would say Master OCXO module design is quite complex though, here we are developing the firmware for the imbedded micros that control both the clock system's functions and the USB card :).  

 

Still a good looking board and defiantly a good move to take the clock off the USB card IMHO. 

OAudio Ltd.

OAudio Supreme - music server.

OAudio RealStream - digital audio components.

 

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...