Go Back   Home > Forums > Source & Line > Digital Source
Home Forums Rules Articles Store Gallery Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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 6th April 2005, 03:17 PM   #1
diyAudio Member
 
Join Date: Apr 2002
Default 74xx74 a good digital output (AES-EBU/SPDIF)driver?

I opened my transport yesterday to find that the digital signal goes through some 74AC74's then into a transformer (for AES-EBU) before reaching the output jacks (SPDIF and AES-EBU).

I am a newbie on digital, but thought that 74ac74, while good (maybe?) for reclocking, was not exactly a great line driver.
Can anyone recommend a driver/buffer I can use for the digital output of the transport. Should this be before or after the output transformer?

As far as possible, please try not to be too cryptic in your advice-this is foreign territory and I need all the help I can get, including where possible, circuit diagrams!

Ryan
  Reply With Quote
Old 7th April 2005, 03:18 AM   #2
Banned
 
Join Date: Feb 2002
Location: As far from the NOSsers as possible
Default NO!!!!!

Avoid AC logic like the plague. Do not use the Q and Q_bar to make a "balanced" output...........it will not work properly.

Jocko
  Reply With Quote
Old 7th April 2005, 07:34 AM   #3
diyAudio Member
 
Join Date: Apr 2002
Default Thanks

Thanks for the input Jocko-you confirmed my suspicions. Any ideas on how to go about "fixing" this digital output:
1. What to replace the AC logic with?
2. If not using Q and Q bar for balanced, what is the alternative
3. Does the output require some sort of buffer-if so, what do you suggest?
  Reply With Quote
Old 7th April 2005, 03:10 PM   #4
Banned
 
Join Date: Feb 2002
Location: As far from the NOSsers as possible
1.) HC works fine. I have used VHC. Looks ok, but to tell the truth, I have never listened to any circuits with it in.

2.) A transformer works. You have to find the right one, and fiddle with it some. Two XOR gates will give differential outputs. You can combine both ideas.

3.) With a transformer, you will need to put a cap before it. Some resistors to lower the level, and limit the current load on the logic gate.

Jocko
  Reply With Quote

Reply


Hide this!Advertise here!

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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
how to DIY MP3 with Dolby Digital and output in SPDIF? audio_novice Digital Source 8 14th December 2007 09:17 PM
Computer coax digital spdif output.. USB?... Sampling rate?? dqswim Digital Source 13 12th November 2005 03:40 PM
SPDIF driver - 74HCU04 output impedance? Adrian Digital Source 14 26th July 2005 01:51 PM
SPDIF coax digital output topologies Vinnie R. Digital Source 27 27th January 2004 12:42 PM
Help-New DVD player and I need some info about the digital (SPDIF) output settings. slicemaster101 Digital Source 12 25th November 2002 10:08 PM


New To Site? Need Help?

All times are GMT. The time now is 12:54 AM.

Page generated in 0.07205 seconds (75.57% PHP - 24.43% MySQL) with 10 queries

Copyright ©1999-2012 diyAudio