[mmerrill99]

Quote:

can I know what Thomas indicated "external + and - supply" are actually going into the 3.3V regulator ?
 
Which means just ground the enable pin, remove the regulator (optional) and supply 'another' 3.3V to the regulator right

Yes those annotated connection points are +3.3V & ground connection points.
You will find grounding the enable pin to be quiet difficult - easier to remove the reg altogether BUT I'm suggesting NOT to do this at all, just do the clock mod as Regal has shown.

 

[regal]

If you decide to remove the regulator you will be going past a point of no return.  This PCB is thin and cheap,  it taks a lot of flux and heat to remove the regulator and probably will pull a trace or two up with it.  Be careful,  its easy to blow up the DIT which takes special solder and tips to remove and replace.

 

[GreenLeo]

Any chance to see the photo of the final version of Regal's mod?  Just want to look at the 75 ohm BNC connector and the new regulator used in the mod. 

 

[regal]

Quote:

Any chance to see the photo of the final version of Regal's mod?  Just want to look at the 75 ohm BNC connector and the new regulator used in the mod. 

I took the regulator out,  running a separate +5V B= just sets up a big ground loop that causes more harm then good.   The connector is self explainitor except TX+ and TX- are reversed,  you'll understand when you order the part.

 

[hawaya]

Hello again JKenny, Regal,
 
My question is can i remove a pulse  trafo from Hiface, if i use a clean 5V (is this safe for unit)?
 
http://hawaya.snimka.bg/details/dax-hiface.508491.19312896,
 
Thanks in advance.

 

[regal]

its safe but not neccesarily smart,  your "clean" 5V just made a big ground loop. I removed the separate 5v+ because it degraded the SQ in my setup. The Texas Instruments DIT4192 datasheet calls for an SC pulse transformer and I assume they know more than us.  Unitl Adum or whomever makes a 480mBS USB isolator and we can galvanically isolate the hiface from the computer I would stick with the pulse transformer.  
 
Quote:

Hello again JKenny, Regal,
 
My question is can i remove a pulse  trafo from Hiface, if i use a clean 5V (is this safe for unit)?
 
http://hawaya.snimka.bg/details/dax-hiface.508491.19312896,
 
Thanks in advance.

 

[hawaya]

Thanks Regal,
 
What do you suggest, to remove the trafo with 5v (I use both positive and negative wire), and switch to dirty computer 5v from usb cable?
 
Regards

 

[regal]

You still have the ground of the PC connected otherwise it won't work right,  you can't isolate the Hiface from the computer,  so the external 5V+ just makes a big ground loop,  we are stuck with the dirty USB 5V+ for now.
 
Quote:

Thanks Regal,
 
What do you suggest, to remove the trafo with 5v (I use both positive and negative wire), and switch to dirty computer 5v from usb cable?
 
Regards

 

[hawaya]

So 5v from computer, the SQ is better? And what if i use 5v from battery?

 

[mmerrill99]

I modified the 5V supply to remove it from the USB input of the Hiface & supplied externally - I get no ground loop hum or noise! 
 
OT. Here's a brilliant idea - a LiFePO4 battery supply for audio - only costs $1,000 to upgrade your equipment. Some people athttp://www.computeraudiophile.com/content/Updated-Battery-technology-RWA think it's a great idea. Now why didn't I think of that 

(charging $1,000 instead of €50, I mean 

)

 

[Zorlac]

Hey Jkeny...have you ever looked into using double-conversion online UPS power? I started reading up on these and apparently they output perfect sinewave power at all times. Would this essentially be the same as battery power to the amp, DAC, etc.? I will probably buy one regardless at some point.

 

[mmerrill99]

So far I haven't heard or been told of any commercial or DIY regulator or PS that beats these batteries for sonics. There may be but I haven't heard about them!
 

 

[hawaya]

Thanks Jkenny, i don't have any hum too with external 5v, but is there any improvement with oscillators, i have with the second device one  small, and one big, or should i use other brand oscillator, with low ppm?

    

 

[mmerrill99]

I meant to say that my 5V was not from a battery & i still don't seem to have a ground loop but I'll investigate further.
 
I've stayed out of the oscillator discussions by & large but I really don't get it. Can I ask you this, what oscillator are you thinking of to replace the smaller osc.? How do you know the replacement one is lower jitter? Are there any specs for the "bad" oscillator - what is it's jitter spec? How does a change of PS make a "bad" oscillator into a "good" sounding one?
 
Have any of these questions been addressed?

 

[hawaya]

Don't get me wrong, i just ask you because you have large experience, with both type, for me the large improvement in SQ came with your 3,3v battery mode.