Go Back   Home > Forums > Source & Line > Digital Line Level

Digital Line Level DACs, Digital Crossovers, Equalizers, 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 1st March 2008, 09:51 AM   #31
Jambo is offline Jambo  United Kingdom
diyAudio Member
 
Join Date: Jan 2008
I also wouldn't describe my design as "ultra high-end", but thought some people here might be interested.

It uses the WM8805 SPDIF receiver (which is a multiplexed version of the WM8804) to receive 2 optical inputs, one coaxial and one USB. This then goes to two WM8740s in dual mono configuration. It is also designed to work with the WM8741 once it is properly available. There are also output filters on the same board, as well as a microprocessor to control the WM8805 from switch inputs and headers for LEDs to show the current input source.

As I said, not "ultra high-end", but feel free to have a look:

Jambo DAC

I hope to have kits available soon - prototype PCBs arriving Monday.
  Reply With Quote
Old 1st March 2008, 10:34 AM   #32
diyAudio Member
 
analog_sa's Avatar
 
Join Date: Aug 2002
Location: Sofia
Quote:
Originally posted by Jambo
I also wouldn't describe my design as "ultra high-end"

No argument here. A pity you couldn't figure out a way to use I2S from the 2707.

Is that your reference amp in the pic?
  Reply With Quote
Old 1st March 2008, 11:20 AM   #33
Jambo is offline Jambo  United Kingdom
diyAudio Member
 
Join Date: Jan 2008
Lol... indeed. Though the WM8805 is such an excellent transceiver it shouldn't make too much difference...

My reference amp? Erm, it's my amp, yes. Nad 3020, love it, apart from the fact that they couldn't seem to get those switch covers to stay in place...
  Reply With Quote
Old 1st March 2008, 01:41 PM   #34
diyAudio Member
 
Join Date: Jan 2002
Location: Cheltenham
I'm interested in hearing what people who say this or that design isn't high end regard as necessary? Price? Specs? A certain design topology?
  Reply With Quote
Old 1st March 2008, 04:07 PM   #35
Jambo is offline Jambo  United Kingdom
diyAudio Member
 
Join Date: Jan 2008
Well.. in my one, as analog_sa hinted, I2S to SPDIF conversion and then back to I2S again isn't as ideal as it could be. Also, many people prefer current out DACs with an external I/V stage.

Price also pays a big part of it, when the O/P stated his budget at $2000 (IIRC) it suggests that he's looking for something a bit mindblowing. I also said it first to avoid being flamed, tho I see analog_sa tried his best anyway
  Reply With Quote
Old 2nd March 2008, 03:33 AM   #36
diyAudio Member
 
Russ White's Avatar
 
Join Date: Jan 2005
Location: Nashville, TN, USA
Send a message via Yahoo to Russ White
Quote:
Originally posted by ezkcdude



The press release for the Sabre DAC said it is $29 in lots of 1000. Can you imagine how expensive it would be in single/small quantities? And to achieve the 134 dB spec (which is for mono), you would need two chips. Otherwise the DNR goes down to 128 dB. Not only that but it's 64LQFP. Most people shy away from SSOP. Even if the Sabre DAC isn't vaporware, I don't see it having any impact on the DIY market.
From the whitepaper:

http://www.esstech.com/techsupp/sabrewp.pdf

Abstract—The Sabre DAC is an octal audio digital to analog
converter each individual channel of which performs with a DNR
of >127dB. If used as a Stereo DAC the performance exceeds
130dB. The THD of each of the eight DACs is less than 0.0001%
(ô€€€120dB). This technical note outlines the critical components of
the Sabre DAC that contribute to these performance levels.

Stereo is 130db DNR. More importantly, the THD is much lower than anything out there if the numbers hold up.

Also note, the DNR/THD limitations seemed to be at the I/V stage... And I think I have an answer for that.

Cheers!
Russ
__________________
Less pulp more juice Twisted Pear Audio.
  Reply With Quote
Old 2nd March 2008, 07:51 AM   #37
diyAudio Member
 
Join Date: Dec 2003
Location: Sydney
http://www.ecp.cc/1865_module.html

this design deserves a serious consideration...

Boky
  Reply With Quote
Old 2nd March 2008, 08:18 AM   #38
diyAudio Member
 
analog_sa's Avatar
 
Join Date: Aug 2002
Location: Sofia
Quote:
Originally posted by Extreme_Boky
http://www.ecp.cc/1865_module.html

this design deserves a serious consideration...

Boky

Something like DacIntheBox on the cheap? Serious stuff.
  Reply With Quote
Old 2nd March 2008, 05:51 PM   #39
diyAudio Member
 
Join Date: Jan 2002
Location: Cheltenham
Quote:
Originally posted by analog_sa



Something like DacIntheBox on the cheap? Serious stuff.
NOS AD1865 also forms the heart of Audio Note's DAC5, which costs very roughly £20K.
  Reply With Quote
Old 3rd March 2008, 08:59 AM   #40
diyAudio Member
 
Join Date: Nov 2005
Location: Greenwich, London, UK
Quote:
Originally posted by Spartacus



You only gain 3dB when you parallel DACs, plus several people are looking at putting PCBs together. The ESS part will be a contender.
Only 3dB?...That 3dB is on a logarithmic scale! Are we really realizing how much 3db is? A 6dB volume change is DOUBLING the volume, the 3dB in paralleling DAC chips in mono is a 50% improvement in whatever aspect the dB measurement is in (SNR, DNR, THD or anything else measured in dB) so 3dB is a significant difference.

It comes down to whether you can hear it, and that always comes down to how good the next bit of your sound reproduction system is (amp and speakers).
  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
Published/DIY ultra-low THD designs? leadbelly Tubes / Valves 10 2nd April 2007 03:41 AM
Ultra high Db levels... where do they come from Lligior Car Audio 5 11th June 2005 11:36 PM
Ultra-high end DIY amp recommendations mlihl Solid State 12 11th September 2004 08:05 PM
3 way ultra high output bostarob Multi-Way 19 3rd June 2002 05:51 AM


New To Site? Need Help?

All times are GMT. The time now is 05:11 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