[lieberung]

  Sorry guys, but i HAVE to say this:
 
Please read ALL posts before asking your question, most questions have been answered in previous posts.
 
@Lieberung: I even "photoshopped" a picture to point at the fuse,,,,,, see http://www.head-fi.org/t/736294/gustard-u12-usb-interface-8-core-xmos-chip/645#post_11318547
 
Have fun 

Thanks! I have tried switching the fuse but still would not start. The seller on Ebay is very understanding and has offered me a new unit if I return this one, so I guess Ill take that offer.

 

[prot]

Would be nice, but all Rubidium clocks at ebay are of very low frequencies, so NOT the ones we need

This thing may provide the needed freqs ... still way too expensive

 

[ginetto61]

Hi just a question
Could a battery based power supply give any kind of improvement to the Gustard U12 performance ?
I mean a 12V SLA battery for instance
A battery would provide complete isolation from mains and very low noise.
Anyone knows how much this unit consumes ?
Thanks a lot, gino

 

[hgpsemaj]

I contacted 'Jay's Audio/Taobao' in respect of rubidium word clock today. In his (i.e. c-jacky.) reply, both of the parts of  45.1584Mhz and 49.1520Mhz are running out. However, ready-made rubidium word clock are available.
 

 
 
 
The quotation is RMB4,000. (i.e. excluding postage.)
 
Surely, it is not my cup of tea, and I still prefer DIY.

 

[hgpsemaj]

  Hi just a question
Could a battery based power supply give any kind of improvement to the Gustard U12 performance ?
I mean a 12V SLA battery for instance
A battery would provide complete isolation from mains and very low noise.
Anyone knows how much this unit consumes ?
Thanks a lot, gino

 
I used to run my DEXA word clock by rechargeable SLA battery on my Meridian CD transport, and, I'm afraid the result was not that desirable. First of all, I'm sure DEXA word clock should consume less power than U12, and I needed to recharge my battery every week at that time. Secondly, unless you use 'Lithium-based Batteries', otherwise the performance would start dropping when you start using the battery.
 
If I'm wrong, please put me right.
 
With kind regards,

 

[ginetto61]

Hi and thanks a lot for the very valuable advice
Still i do not love that toroidal transformer ... toroidals have a wide bandwidth ... they let every noise in the mains go through to the circuits.
Maybe even some high quality SMPS would be better (just a guess this one of course).
Thanks again, gino

 

[hgpsemaj]

I've encountered couple of external power supplies, when I opened it up, surprise..surprise...it just consists of 1 x transformer; 1 x capacitor; 1 x regulator and 1 x diode, of course is wrapped up by a shiny metal work. And, they price it well over US$1,500.
Well... that is the reason I always prefer DIY, unless go for those flagship items.
 
Look and beware, one of those uncompromised design;
 

 

[rb2013]

  Hi and thanks a lot for the very valuable advice
Still i do not love that toroidal transformer ... toroidals have a wide bandwidth ... they let every noise in the mains go through to the circuits.
Maybe even some high quality SMPS would be better (just a guess this one of course).
Thanks again, gino

Another solution could be an external PS filter - better PS cable and Aqvox linear regulated filtered USB PS. The Aqvox would be only for switching purposes, as it would feed current all the time, one would have to be careful to be sure it was unplugged before disengaging any of the signal cords (as the protection circuit would not be engaged otherwise).
 
All reversible of course. 
 
I've had good success with Richard Gray Pro 400 and the Shunyata Venom PC.  Have not tried the Aqvox - as I had sold them when I bought the U12s and sold my Musiland USB 3.0's

 

[ginetto61]

Hi i guess this is a for an analog preamp or similar
Mine is only a feeling but i think that analog is less picky regarding power supply quality.
Digital is very very delicate power supply wise ... both clock and dac circuits.
Almost all the modifications once very popular for cd players were addressing the power supply of the digital section ... almost all.
Along with a better quartz of course.
An extremely clean and steady voltage is mandatory for digital from what i understand.
I saw even batteries used for this.
 
I have some other very cheap usb to spdif converters using only power from usb.
I have bought a lithium battery pack to be used with usb powered devices.
It is a 15Ah pack.  So it should last for some days ... but i will see. And listen of course.
I am very curious to listen for any improvement in sound using the battery pack.
I am not expecting great performance from these very cheap converters.
Still i will never know until i try.
Thanks again for the very interesting advice.
Kind regards, gino

 

[prot]

I contacted 'Jay's Audio/Taobao' in respect of rubidium word clock today. In his (i.e. c-jacky.) reply, both of the parts of  45.1584Mhz and 49.1520Mhz are running out. However, ready-made rubidium word clock are available.




 


The quotation is RMB4,000. (i.e. excluding postage.)

Surely, it is not my cup of tea, and I still prefer DIY.

I think $650 is a very good price for such a device ... pretty hard to beat even when you DIY. The rubidium standard itself costs $2-300, than you need a case, various cables & connectors, highend power source and a highend circuit to generate the two clocks and keep the rubidium precision. $350 for all that is pretty reasonable ... even cheap I would say.

Anyway, this is a much too expensive mod for me. But I'm very curious to hear about the improvements it *may* bring.

 

[rb2013]

  Hi i guess this is a for an analog preamp or similar
Mine is only a feeling but i think that analog is less picky regarding power supply quality.
Digital is very very delicate power supply wise ... both clock and dac circuits.
Almost all the modifications once very popular for cd players were addressing the power supply of the digital section ... almost all.
Along with a better quartz of course.
An extremely clean and steady voltage is mandatory for digital from what i understand.
I saw even batteries used for this.
 
I have some other very cheap usb to spdif converters using only power from usb.
I have bought a lithium battery pack to be used with usb powered devices.
It is a 15Ah pack.  So it should last for some days ... but i will see. And listen of course.
I am very curious to listen for any improvement in sound using the battery pack.
I am not expecting great performance from these very cheap converters.
Still i will never know until i try.
Thanks again for the very interesting advice.
Kind regards, gino

Well the Richard Gray acts as a power stabilizer and storage system, it also reduces power system ground interference.  It's improved every DAC I've tried it with (around a half dozen so far).  Battery powered pre-amps are not new -especially phono pre-amps.  I have owned a few.  They are very pure, but seem to lack dynamics.  Have not seen many battery powered DACs or CD players though.
 
I have had battery powered USB devices before - as I posted on page 2 of this thread:

Originally Posted by rb2013 

http://www.acopian.com/mobile/pages.aspx?page=wide-l-goldbox-infinity-m
I did a lot of experimentation with my M2Tech Evo and Audiopilleo 2, with battery ps's. They were smooth, but seemed to rob the dynamics. Wound up building my own ultra quiet linear ps, based on the Acopian 'Gold Box' infinity. Really sounded much better. More detail and way more dynamic. But the Musiland 3.0 USB USD sounded better still with the Aquvox linear ps.

For me the battery route didn't do it. I found this same issue with the battery powered phono preamp I once had. Polite but boring. YMMV.

It looks like Gustard went the extra mile in the power supply design. 

On the Richard Gray Quote:

 

Parallel Power Delivery​

​

Patented parallel iron-core inductor technology is proven (after 1 million installations and counting) to provide instant current –on–demand to power efficiently today’s High Performance-Current hungry AV components and electronic systems.​

​

​

Stabilizes AC Power​

​

Enhances AV performance​

​

Improves start up characteristics and Inrush response​

​

Provides additional Balanced AC Surge protection.​

I would be interested in adding additional power filtering beyond the 400Pro.
 
As I mentioned I used the Aqvox linear PS with my Musiland 3.0's, it  does a very good of filtering: http://www.aqvox.de/usb-power_en.html

100mHz digital scope, one vertical square are 10mV - this shows 50 - 60mV

A typical power supply of notebook PC

Sources of disturbances (ripple & noise) inside a computer:

1. Backlight of computer monitors: The necessary high voltage of approx. 900 V for LCD/TFT monitors is generated by inverters which produce ripple and noise.

2. Hard disks (internal + external): The actuators of the recording/reading heads produce interference voltage with each positioning or stop move.
3. Clock generators and chips like e.g. the CPU, northbridge, RAM or graphics adapter cause disturbances and noise.
4. Power supplies of notebooks and desktop PCs are not designed for lowest interference voltage and noise, since this is extra costs, not necessarily needed.

5. DC/DC converter producing up to 100mV ripple and noise.
and so on...

 

 

100mHz digital scope, one vertical square is 10mV - this shows 40 - 50mV

Interference voltage and noise of USB power from a computer.
Even the use of a battery-powered notebook brings little help.
A typical picture of 5 Volt USB power with 40 mV ripple & noise from a desktop PC without running access of the hard disk. 

 
Cheers!

 

[abartels]

 
Another solution could be an external PS filter - better PS cable and Aqvox linear regulated filtered USB PS. The Aqvox would be only for switching purposes, as it would feed current all the time, one would have to be careful to be sure it was unplugged before disengaging any of the signal cords (as the protection circuit would not be engaged otherwise).
 
All reversible of course. 
 
I've had good success with Richard Gray Pro 400 and the Shunyata Venom PC.  Have not tried the Aqvox - as I had sold them when I bought the U12s and sold my Musiland USB 3.0's

I'm using a Belkin powerflter PF50 (european model), it's great, sadly Belkin doesn't produce them anymore 

 

[MINORISUKE]

Can anybody tell whether it is possible to change latency with XMOS USB Audio driver (2.23.0) which comes with U12?
Copying TSUBAudioCpl.exe from WaveIO setup seems not to function.
For JPLAY, I need KS, which means I should stick to XMOS driver.

 

[rb2013]

  I'm using a Belkin powerflter PF50 (european model), it's great, sadly Belkin doesn't produce them anymore 

Too bad they don't make them anymore.  Does it help?
 
I use one of these APC® Back-UPS® BN600G for my PC - but didn't seem to help - in fact was a tiny step backward on the Gustard

 

[abartels]

  Hi i guess this is a for an analog preamp or similar
Mine is only a feeling but i think that analog is less picky regarding power supply quality.
Digital is very very delicate power supply wise ... both clock and dac circuits.
Almost all the modifications once very popular for cd players were addressing the power supply of the digital section ... almost all.
Along with a better quartz of course.
An extremely clean and steady voltage is mandatory for digital from what i understand.
I saw even batteries used for this.
 
I have some other very cheap usb to spdif converters using only power from usb.
I have bought a lithium battery pack to be used with usb powered devices.
It is a 15Ah pack.  So it should last for some days ... but i will see. And listen of course.
I am very curious to listen for any improvement in sound using the battery pack.
I am not expecting great performance from these very cheap converters.
Still i will never know until i try.
Thanks again for the very interesting advice.
Kind regards, gino

 
Sorry for saying this Ginetto61, but it seems to me you haven't any clue about how analogue / digital stages perform on poor psu's.
A well developed and build linear psu will ALWAYS be the BASE of good analogue or digital audio equipment.
 
My 30yo diy mosfet class-A pré-amp (which i have build myself) has 5 seperate transformers and and all seperated regulaterstages with pi-filters.
I didn't develop that psu for fun, it's absolutely needed when you want the best SQ.
 
My first developed dac, build on CS4398, had all seperate powerstages, but sadly only one toroidial transformer with seperate windings.
Seperate transformers would take this dac to a much higher level, but there wasn't any room left in housing.
 
Also my diy mosfet class-A poweramp uses 2x 1000VA toroidal transformers with 160.000 uF Rifa / Roederstein caps, it's really not for fun that one build
a good psu for analogue equipment. It's a necessity when you want to deliver the best SQ.
 
Sorry, but i had to comment on this,,,,, 
 
It all has to do with how much one will invest in a product.
 
Like our Gustard U12, it's a very nice developed and build DDC which delivers outstanding SQ for the buck, and one can modify it with simple tools.
But, buying clocks and other stuff which costs 5 times as much as the U12 is as buying a VW Golf, strip it down and put a Porsche engine in it............
 
Just my 5 cents,