24 bit / 192 kHz Tube DAC questions - 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 28th April 2003, 07:36 AM   #1
diyAudio Member
 
Join Date: Apr 2003
Location: Houston, TX
Default 24 bit / 192 kHz Tube DAC questions

i would like to build a 24/192 DAC with a tube output stage but am not really sure where to begin looking for project guidlines. although i have some experience with electronics i am pretty much a newbie when it comes to D/A conversion. i have found a few Tube dac projects that have circuit boards available here and here for example but both seem to be built for 16/44 operation. are there any plans out there for the type of projet i'm looking for? i am not against learning the theory and applying it to create my own design but i have no idea where to begin. usually i learn details about my project as i'm building...but i feel like with this kind of thing it may require a lot more background knowledge then what i have at the moment.

thanks for any help

~Nasser
  Reply With Quote
Old 28th April 2003, 11:23 PM   #2
diyAudio Member
 
Join Date: Oct 2002
Location: Seattle
Well, I can tell you I've been having a tough time trying to design a tube output stage into an AD1955. Seems like this DAC doesn't like passive I/V conversion according to the manufacturer. That rules out a simple I/V resistor. I guess an omp amp I/V convertor feeding a tube stage is the best I could do. I even looked into a Zap Filter but that won't work well either due to high current output of this Dac. This according to the desinger anyway. A delta sigma design DAC with voltage outputs would be much much easier to match a tube stage up to I think.

-Ed
  Reply With Quote
Old 29th April 2003, 05:27 AM   #3
diyAudio Member
 
Join Date: Apr 2003
Location: Houston, TX
oh ok...yeah i was thinking about using the CS43122 chip...which is a Delta sigma design. but i'm trying to find info on creating the digital conversion portion of the overall DAC...i think that if i can cmoe up with a decent design for that then i can borrow other peoples tube output stage and be ok...at least in theory...
  Reply With Quote
Old 29th April 2003, 12:50 PM   #4
diyAudio Member
 
Join Date: Oct 2001
Location: .
Quote:
Originally posted by Overlord
oh ok...yeah i was thinking about using the CS43122 chip...which is a Delta sigma design. but i'm trying to find info on creating the digital conversion portion of the overall DAC...i think that if i can cmoe up with a decent design for that then i can borrow other peoples tube output stage and be ok...at least in theory...

The R-2R ladder dac is probably the only feasible dac for diy, if you really are determined to design your own conversion stage.
Laser trimming the resistors for the current sources might prove
a bit tricky for a diy'er though.

ray.
  Reply With Quote
Old 29th April 2003, 05:14 PM   #5
diyAudio Member
 
Join Date: Apr 2003
Location: Houston, TX
hmmm...yeah after a lot of research i'm having quite a bit more trouble then expected...then again a few days of research isnt really a whole lot. especially while trying to learn this stuff from scratch. maybe i can use a predefined conversion stage. but i'm not sure if i have the general idea down or not...

this the gist of what i am trying to do....please correct me if something is screwy...


SPDIF ->Transformer ->reciever chip(CS8416) -> ??? (not sure if i need to reclock or something at this stage -> DAC chip (CS43122) -> since it has a voltage output i should be able to couple it directly to a Tube Output stage right? since i dont have to worry about I/V conversion?
  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
2 tube questions electronjohn Tubes / Valves 4 7th April 2010 07:32 AM
DIY Tube Amp Questions john65b Tubes / Valves 95 24th April 2008 05:22 PM
Questions about first tube PSU! luvdunhill Tubes / Valves 2 18th September 2007 06:06 PM
2 Tube questions, Trout Tubes / Valves 5 14th April 2006 09:57 PM


New To Site? Need Help?

All times are GMT. The time now is 02:57 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