[rb2013]

 

 

Nice!  It would be nice to see someone step up and do linear regulated PS like Berkley.  Good to see the Talema in there though.

 

[m0reilly]

  How'd you hook up an external linear PSU to Gustard U12? I do not see any input DC connector.
 
Btw, I've put about 50 hours on my U12. So far the sound is better than going to direct to the USB input on my dac which uses amanero USB board. The sound is more musical, little bit more rounded as a result some inferior harsh sounding music sounds quite a bit better and I also hear a less congestion in upper mid/lower high frequency. There may have been a very slight reduction in dynamics. But overall the improvement is very very nice for money I spent on the U12. 

what output are you using from the u12 to dac?

 

[Radiohead99]

I'm using the spdif output and a generic spdif cable. OTOH my usb cable is pretty high end.

 

[hgpsemaj]

  How'd you hook up an external linear PSU to Gustard U12? I do not see any input DC connector.

 
Modification works are needed. I am consideration the following:
 
(i) Use the external PS to replace the existing transformer.
 
or
 
(ii) NDK NZ2520SD 3.3V 49.152Mhz  and 45.1584Mhz could use the existing power supply from the main circuit board. However, OCXO need an external 5V/1A power supply source, and also, need to connect the 'GND pin' back to the external power supply's GND.
 
So, I got a feeling this external linear PS could upgrade my U12.

 

[Stillhart]

 
Moving the PC far out of the picture made a large difference. I am actually using a dongle with ethernet in and USB out to the DACs now, with the backend sitting on a general purpose server.
Did not expect it to be better than my existing dedicated machines with Foobar, Audirvana and Amarra. I was pleasantly surprised
 
Sotm make such a device and I also built  few from the Squeezebox touch and the little ARM boards (Raspberry Pi and Beaglebone Black <-- these cost less than the 2pcs of Crystek 957 XOs I used on my USB interface).

 
So the U12 works with Raspberry Pi?  I think I read something earlier in the thread that XMOS drivers are native to linux so I believe it should work, but I wanted to confirm.

 

[roman410]

   
So the U12 works with Raspberry Pi?  I think I read something earlier in the thread that XMOS drivers are native to linux so I believe it should work, but I wanted to confirm.

I do not have Rasberry Pi, just my Gustard U12 work perfect with my linux  Squeezebox touch, its native no drivers needed. Also I decided sale my Gustard, used 60hr, PM my if you interesting.

 

[Stillhart]

 
I do not have Rasberry Pi, just my Gustard U12 work perfect with my linux  Squeezebox touch, its native no drivers needed. Also I decided sale my Gustard, used 60hr, PM my if you interesting.

 
Bummer, if I'd known 2 days ago...

 

[b0bb]

   
So the U12 works with Raspberry Pi?  I think I read something earlier in the thread that XMOS drivers are native to linux so I believe it should work, but I wanted to confirm.

I am using the RPi with my Breeze Audio interface. It is an older XMOS chip.
 
My RPi runs Tiny Core Linux which has the USB 2.0 Asynch mode in-kernel audio drivers that works with any compliant USB interface (XMOS is one).
 
On my Breeze Audio this goes up to 192kHz and on my other DACS with the Amanero interface I can do up to 384kHz and DSD128.
Anything above that say DSD256/768kHz would require a custom driver.
 
Not sure about the U12 but if you plug in a U12 into a recent  linux box (Linux 3.0 and above) and get audio working, it will work with the RPi  since it is the same in-kernel driver.
 
Here is the linux version on my RPi 2
Linux MightyPi 3.18.7-piCore #1 SMP PREEMPT Sun Feb 22 20:18:02 UTC 2015 armv7l GNU/Linux

 

[b0bb]

  Nice!  It would be nice to see someone step up and do linear regulated PS like Berkley.  Good to see the Talema in there though.

The Melodious you bought looks like a better implementation.
The transformers on the Melodious at the spdif RCA and AES outputs serve to provide galvanic isolation between the board and the DAC but also between various DACs if you plug in more than one.
 
If you look at the Berkeley, only the isolated site is powered by the power supply, power for the XMOS comes from the host, on this, isolated and non-isolated sides go into the same power supply, RF noise can couple thru the Talema quite easily, this greatly diminishes the the value of the isolators. If the USB interface side can be powered from the host, this may improve matters.

 

[abartels]

  Both 'Melodious MXU8' and 'Tanley Audio Asynchronous USB interface' use Talema transformer and separate their transformer with the main circuit board, the following external linear power supply may assist U12 to regain those losing ground:
 
http://item.taobao.com/item.htm?spm=a1z10.1-c.w4004-10606815601.9.ho7Xhu&id=44614422828

Thank you for that link, i think i will try that one!!

 

[hgpsemaj]

  Thank you for that link, i think i will try that one!!

Hello Abartels,
 
Are all the pins location of NDK identical to our TCXO? I mean NDK's Stand-by pin and Vcc pin. Please advise.
 
Regards,

 

[abartels]

Listening impressions after replacing Gustard Crystals with NDK NZ2520SD's - 50 hours burn-in time
 
 
In one word: AMAZING
 
There's soo much depth in soundstage, the ease of music reproduction, airyness, tonal balance, very tight and powerfull deep bass,
"complete darkness around voices", never thought this would happen!!
 
Don't forget, it has only burned-in for 50 hours, it will gain more after another 80 hours.
 
My plans:
 
1- Replacing the onboard smd crystal for XMOS with NDK crystal
2- Using external Linear PSU instead of replacing onboard regulators (thanks for the link hgpsemaj)
 
Maybe i'm going to build my own linear psu, isn't that difficult to accomplish, found a nice case that would nicely fit next to U12:
 
http://www.ebay.com/itm/B-0905-black-Full-Aluminum-Enclosure-mini-amplifier-case-Preamp-box-PSU-chassis-/111627609509?pt=LH_DefaultDomain_0&hash=item19fd8625a5
 

 
This one is only $22 including int. shipping!!
 
 
Btw the Melodious looks very promising and design is very easy to modify, sadly it doesn't do DSD otherwise i would consider bying one.
The Tanley Audio looks very good, but, who designs this kind of superb device with USB input at it's front panel?!?!?!?!? It's a no go for me, sorry.

 

[abartels]

  Hello Abartels,
 
Are all the pins location of NDK identical to our TCXO? I mean NDK's Stand-by pin and Vcc pin. Please advise.
 
Regards,

Yes, pinout is the same

 

[MINORISUKE]

Originally Posted by abartels /img/forum/go_quote.gif
 
.....
Btw the Melodious looks very promising and design is very easy to modify, sadly it doesn't do DSD otherwise i would consider bying one.
.....

I ordered mine before rb2013, but it is still on the way (currently in Leipzig, Zollamt).....
The reason why I ordered it is its DSD output from RJ45.  MX-U8 should support DSD, as described in the store's Web site.

 

[hgpsemaj]

  Listening impressions after replacing Gustard Crystals with NDK NZ2520SD's - 50 hours burn-in time
 
 
In one word: AMAZING
 
There's soo much depth in soundstage, the ease of music reproduction, airyness, tonal balance, very tight and powerfull deep bass,
"complete darkness around voices", never thought this would happen!!
 
Don't forget, it has only burned-in for 50 hours, it will gain more after another 80 hours.
 
My plans:
 
1- Replacing the onboard smd crystal for XMOS with NDK crystal
2- Using external Linear PSU instead of replacing onboard regulators (thanks for the link hgpsemaj)
 
Maybe i'm going to build my own linear psu, isn't that difficult to accomplish, found a nice case that would nicely fit next to U12:
 
http://www.ebay.com/itm/B-0905-black-Full-Aluminum-Enclosure-mini-amplifier-case-Preamp-box-PSU-chassis-/111627609509?pt=LH_DefaultDomain_0&hash=item19fd8625a5
 

 
This one is only $22 including int. shipping!!
 
 
Btw the Melodious looks very promising and design is very easy to modify, sadly it doesn't do DSD otherwise i would consider bying one.
The Tanley Audio looks very good, but, who designs this kind of superb device with USB input at it's front panel?!?!?!?!? It's a no go for me, sorry.

 
Say, if you decide to build your liner power supply for U12
 
(i)  Do you consider 'R Core Transformer' would outpace Talema?
 
http://detail.tmall.com/item.htm?spm=a230r.1.14.1.72lSoM&id=12719221696&ad_id=&am_id=&cm_id=140105335569ed55e27b&pm_id=&abbucket=17
 
 
(ii)  According to our post#1074, If power for the XMOS not comes from the host, isolated and non-isolated sides go into the same power supply, RF noise can couple thru the transformer quite easily. In order to avoid this sort of interference to each other, shall we adopt 2 transformers?
 
 
It is just my two cents for one step closer to Berkeley Alpha USB.