DAC 2496 (AK4393) DAC KIT With CS8416+AK4393+5532 - Page 158 - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 11th April 2012, 03:19 AM   #1571
billo44 is offline billo44  United Kingdom
diyAudio Member
 
billo44's Avatar
 
Join Date: Sep 2009
Location: Nagano Japan
Quote:
Originally Posted by billo44 View Post
All seem OK as per attached picture (small print sorry).
Just to point out the picture in my previous post is from Dario with my measured values annotated. It isn't my board.
If you click and then click the full size button bottom left it is readable.

Thanks everyone.
Bill
  Reply With Quote
Old 11th April 2012, 05:40 AM   #1572
diyAudio Member
 
Join Date: Feb 2010
Quote:
Originally Posted by billo44 View Post
Just to point out the picture in my previous post is from Dario with my measured values annotated. It isn't my board.
If you click and then click the full size button bottom left it is readable.

Thanks everyone.
Bill
Did you try putting back the 5532? I managed to kill 1 ak4396 and 1 ak4395 so youre not the only one
  Reply With Quote
Old 11th April 2012, 06:42 AM   #1573
diyAudio Member
 
Join Date: Nov 2009
Location: UK, Manchester
Quote:
Originally Posted by ClaveFremen View Post

No, Salas shunt is for sure superior.

I think that probably a Salas shunt is overkill since opamps have high PSRR, while in a simple discrete circuit, like the DCB1, PSRR is much lower.
do you mean that there is no point and it doesn't worth to make separate salas just for opams (ex. some simple headphone amp or opamp output of CD player, etc). I was wandering is it ok to use your shunt with other regs - 7808-7812 or add some variable R to LM317 version?
Attached Images
File Type: png MINI2496 PS.png (67.5 KB, 442 views)
  Reply With Quote
Old 11th April 2012, 08:21 AM   #1574
Reality first!
diyAudio Member
 
ClaveFremen's Avatar
 
Join Date: May 2005
Location: Milan, Italy
Quote:
Originally Posted by billo44 View Post
All seem OK as per attached picture (small print sorry).
Bill, the values around the 9V regulator seems way too low but it shouldn't be a problem...

Now, apart no analog output, the leds behave correctly?

Quote:
Originally Posted by dtses View Post
do you mean that there is no point and it doesn't worth to make separate salas just for opams (ex. some simple headphone amp or opamp output of CD player, etc).
Not as a general rule.

Probably a Salas shunt would sound better than my shunt even with opamps but I suppose difference wouldn't be much thanks to opamps PSRR, IMHO.

But I didn't any direct comparison.

Quote:
Originally Posted by dtses View Post
I was wandering is it ok to use your shunt with other regs - 7808-7812 or add some variable R to LM317 version?
It's not clear... do you mean using 78xx instead of LM3x7 in current sources?
__________________
Dario
ClaveFremen "Bailando Salsa en el Sietch"
  Reply With Quote
Old 11th April 2012, 08:52 AM   #1575
50AE is offline 50AE  Bulgaria
diyAudio Member
 
Join Date: Jul 2011
Location: Sofia, Bulgaria
My AK4396 chips have arrived today!! Hopefully tonight this DAC will be singing! This is what I did yesterday:

Click the image to open in full size.
http://store.picbg.net/pubpic/83/FF/...98d54483ff.png

Click the image to open in full size.
http://store.picbg.net/pubpic/D2/89/...1f2d6dd289.jpg
  Reply With Quote
Old 11th April 2012, 09:22 AM   #1576
bcmbob is online now bcmbob  United States
diyAudio Member
 
Join Date: Dec 2009
Location: Bay City, Michigan
Bill, did you start with a bare board or modify one that was previously assembled and functioning?
__________________
Bob M.
"Arrange Whatever Pieces Come Your Way."
  Reply With Quote
Old 11th April 2012, 10:13 AM   #1577
diyAudio Member
 
Join Date: Nov 2009
Location: UK, Manchester
Quote:
Originally Posted by ClaveFremen View Post
It's not clear... do you mean using 78xx instead of LM3x7 in current sources?
hi Dario,

just small improvement over existing opamp PSU in another diy dac (WM8740). As there is no place in the box for another salas shunt, your mod looks very nice.
The regs are 7812 & 7912, so I thought whether could I add marked part (att) between reg and cap? Is there any calculation for R104 & D105 or it's already done in accordance to BD139?
Attached Images
File Type: png opamp.png (19.6 KB, 432 views)
File Type: png shunt.png (84.4 KB, 439 views)
  Reply With Quote
Old 11th April 2012, 10:57 AM   #1578
Reality first!
diyAudio Member
 
ClaveFremen's Avatar
 
Join Date: May 2005
Location: Milan, Italy
Quote:
Originally Posted by dtses View Post
The regs are 7812 & 7912, so I thought whether could I add marked part (att) between reg and cap?
No, they replace completely the 7x12s.

And you shouldn't omit the LM317 CCSs... you can replace them with current setting resistors but you loose 50% of the performace improvement.

Quote:
Originally Posted by dtses View Post
Is there any calculation for R104 & D105 or it's already done in accordance to BD139?
You must choose the zener voltage (Vout = Zener voltage + 0.6V) and size the current setting resistors R101/R201 (1.25V/R=Iout + 15mA).

R104/R204 are sized for a 500mW zener.
__________________
Dario
ClaveFremen "Bailando Salsa en el Sietch"
  Reply With Quote
Old 11th April 2012, 12:11 PM   #1579
diyAudio Member
 
Join Date: Mar 2012
Quote:
Originally Posted by bcmbob View Post
Billo - A shot in the dark - I had a very strange problem when wiring my JC-2 pre (yellow board). If both 0V wires were connected to the PCB the unit would not function. After combining them in a terminal block and running a single wire to the board, everythings works. Makes no sense to me ( I was going to post about it) but believe me, it was the only way I could get the pre to work.

Might be worth a try. In the photo the Lighter Note is also powered by the same toroid, but the problem was there even when that circuit was not involved.
Hi Bob,

It might be that you made a simple mistake. I see the cables (for secondary voltages) are same color. The secondary windings are actually polarized.
Not like positive or negative, but they have a "beginning" and an "end" of the winding. It does not matter how you connect them, as long as the cable to the center point of the pre-amp or DAC have two cables.

One should be "winding 1 END" and the other should be "winding 2 BEGIN". The beginning of a winding is often shown with a dot or a marking.
If you do that wrong, then they compensate themselves, resulting in 0 V (or very close to zero). If that happens, swap two cables from ANY winding.
  Reply With Quote
Old 11th April 2012, 01:25 PM   #1580
diyAudio Member
 
Join Date: Nov 2003
Location: Near PARIS
Quote:
Originally Posted by ClaveFremen View Post
Bill, the values around the 9V regulator seems way too low but it shouldn't be a problem...

Now, apart no analog output, the leds behave correctly?



Not as a general rule.

Probably a Salas shunt would sound better than my shunt even with opamps but I suppose difference wouldn't be much thanks to opamps PSRR, IMHO.

But I didn't any direct comparison.



It's not clear... do you mean using 78xx instead of LM3x7 in current sources?

Hello Dario ,

I would like to check your Shunt reg on the AK4396 5v Ana ,i have a question about the BD 139 .
Can i replace it by an equivalent smaler ?

Thanks

Serge
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
AK4393 burn... CIMONE Digital Line Level 5 24th June 2011 02:12 PM
AK4393 to CS4223? CIMONE Digital Line Level 0 13th December 2009 02:30 PM
AK4393 Serial Configuration Problem Aoxomox Digital Line Level 0 20th March 2009 05:25 PM
AK4393, CS8413 and CS8414 Data Sheets Blue_Max Digital Source 0 23rd December 2004 01:37 PM


New To Site? Need Help?

All times are GMT. The time now is 01:38 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2