Wolfson WM8740 DIR9001 PCM2706 DIY DAC - Page 11 - 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 16th January 2012, 08:39 PM   #101
diyAudio Member
 
Join Date: Nov 2009
Location: UK, Manchester
you mean swapping quartz to dedicated clock? (pls see att.)
according to the scheme that would affect only usb input.

btw, I didn't change all stock resistors and film caps, hope that it's not so grave as elkos and regulators.
Attached Images
File Type: png quartz.PNG (30.3 KB, 639 views)

Last edited by dtses; 16th January 2012 at 08:46 PM.
  Reply With Quote
Old 17th January 2012, 10:01 PM   #102
diyAudio Member
 
cobretti's Avatar
 
Join Date: Feb 2011
Location: Taxachusetts
DIR9001 receiver has actually built in clock. Never mind. That cheapo crystal you circled is probably OK for USB input in this application. I use my DAC with SPDIF connection primarily, feeding it straight from Xonar sound card instead of using USB as I did before. I think it sounds better that way. I am just lacking 192kHz sampling, that DAC can not handle.
  Reply With Quote
Old 20th January 2012, 01:30 AM   #103
diyAudio Member
 
Join Date: Feb 2010
Here's some pics from a Azur 640C. It has 2 8740 in dual differential mode. It uses 6 NE5532. There are some little black SMD on the voutrp, voutlp, voutrn and voutln. Anyone have any ideas what these are for?

Click the image to open in full size.

Uploaded with ImageShack.us

Click the image to open in full size.

Uploaded with ImageShack.us

Click the image to open in full size.

Uploaded with ImageShack.us
  Reply With Quote
Old 21st January 2012, 12:46 PM   #104
diyAudio Member
 
cobretti's Avatar
 
Join Date: Feb 2011
Location: Taxachusetts
Probably I/V stage input resistors.
  Reply With Quote
Old 21st January 2012, 01:11 PM   #105
diyAudio Member
 
Join Date: Jan 2012
Hi everyone has someone get the circuit diagram of the DAC from the supplier ?
  Reply With Quote
Old 22nd January 2012, 09:52 AM   #106
Chii is offline Chii  United Kingdom
diyAudio Member
 
Join Date: Sep 2011
Hi all Ive just started building one of these too, i plan to build 2 long turm

The kit I have is a 1.5 version which has a larger crystal package being used unfortunatly the caps and other parts on this kit are fakes so I am pretty much ordering everything in from scratch.

I have a question about the rectifiers two of mine are shatterd will Schottky SR5100, 5 A 100V be ok for this role?

With thanks

Andy
  Reply With Quote
Old 26th January 2012, 10:20 AM   #107
diyAudio Member
 
Join Date: Nov 2009
Location: UK, Manchester
Quote:
Originally Posted by Antonside View Post
Hi everyone has someone get the circuit diagram of the DAC from the supplier ?
I've got it from the seller, see 1st page.

Chii

you can use it, but that would be like overkill for power supply. I replaced stock fakes with fast 1N5819. Moreover they are like almost free.

Btw, where did you get 1.5 version? Could you please attach any pics?

2 all

I'm thinking about replacing all resistors with Dale 1% 1/4w and 4 in parallel per channel on the opams' output. How do you think, would that be a noticeable improvement?

The second upgrade should be shunt regulated PS instead of 7812 & 7912 regulators for opams, though not sure if I have space left for that...

Last edited by dtses; 26th January 2012 at 10:25 AM.
  Reply With Quote
Old 27th January 2012, 09:27 AM   #108
Chii is offline Chii  United Kingdom
diyAudio Member
 
Join Date: Sep 2011
Hi DTSES

eBay - The UK's Online Marketplace is the auction I got the kit from.

[image]
[/image]
[image]http://img03.taobaocdn.com/imgextra/...!!88221699.jpg
[/image]

Shows the new layout, the Board it self is nicely made however everything exsept the IC's and resistors are questionable.

Thanks for the tip on the 1N5819 I orderd 100 as you said nearly free!

Once I have all the replacement parts I will post images of my kit at the moment its a but of a mess because I am changing what I can out for better parts.
  Reply With Quote
Old 27th January 2012, 02:40 PM   #109
diyAudio Member
 
Join Date: Jan 2012
Ive got 1.5 version too. I replaced the diodes and regulators to originals and i ordered ELNA Cerafine caps from ebay but i afraid that they are fake too
  Reply With Quote
Old 28th January 2012, 06:43 AM   #110
Chii is offline Chii  United Kingdom
diyAudio Member
 
Join Date: Sep 2011
At this point i have dale 1% resistors on order to put in instead of the ones supplied, Cerafines for the 1uf, 220uf and larger voltage 47uf, Oscons for the 47uf 16v. Rifa's for the 3300uf and all of the film caps are now WIMAs. Ive also changed the op amps out for a spare set of BB627BP's i had on the shelf.

I am hoping that this produces something that will challenge my modded delta 290's and alpha 9's to show what there capable of. If not it will be relegated to the media center in the bedroom.
  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
cs8414 & wm8740 dac (one dac chip) sparkle Digital Line Level 28 28th March 2012 01:10 PM
New WM8740 DAC lordearl Digital Source 4 3rd May 2010 09:51 AM
DIY Dac PCBS ( DIR9001,DF1706,PCM1704) rudee Swap Meet 1 22nd April 2009 02:04 AM
Problem DIY DAC / WM8740 ah79 Digital Line Level 7 14th March 2009 05:20 PM


New To Site? Need Help?

All times are GMT. The time now is 12:30 AM.


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