New DAC born - 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 8th July 2003, 09:16 PM   #1
diyAudio Member
 
Join Date: Jun 2003
Location: HK
Default New DAC born

Hi all,

Just complete my first NON-OS TDA1543 DAC.

The 1543 is operated at 8V, Riv is 1k5 and Rref is 1k.

Well, the sound is refreshing and musical. When comparing to my previous PCM63 DAC, this little converter sounds more natural.

But the story never ends..........
Attached Images
File Type: jpg dsc00493.jpg (66.6 KB, 1199 views)
  Reply With Quote
Old 8th July 2003, 09:27 PM   #2
diyAudio Member
 
Join Date: Jun 2003
Location: HK
Default its little brother.....

after some listening, I decided to try something other than passive I/V.

First thing drawing my attentiion was Rudolf's simple I/V for the 1543.

The new DAC using this active I/V was built and the sound is even better, more dynamics, more details and the background is more quiet than the original passive version.

Next I will try to improve the supply section, new BJTs, new output Caps ............

BTW, I would like to thank Rodolf for sharing his I/V design.

Cheers.
Attached Images
File Type: jpg dsc00496.jpg (75.5 KB, 1175 views)
  Reply With Quote
Old 8th July 2003, 10:15 PM   #3
fedde is offline fedde  Netherlands
diyAudio Member
 
Join Date: Jul 2002
Location: Eindhoven, the Netherlands
Send a message via ICQ to fedde
Nice work!

Good luck in your adventures...

Fedde

ps. And try a passive version with 2.4k and 3.8 Vdc level!
__________________
http://www.fedde.nu, gainclone and non-oversampling DAC audio projects and kits...
  Reply With Quote
Old 9th July 2003, 08:02 AM   #4
rbroer is offline rbroer  Netherlands
diyAudio Member
 
rbroer's Avatar
 
Join Date: Mar 2002
Location: Netherlands
MDlover,

Looks really nice

Since my pcb's are really tight, it's hard to try some other things.

With the active I/V there are some things you could try:

Try different supply voltages for the TDA1543,
like 5V, 6V, 7V, 8V to hear if there are any differences (my guess is it will be subtle compared to passive IV)

Try different voltages on the base of the common base transistor
(try varying the 4.7k resistor setting the current through the two leds)

Increase the positive rail; this enables you increase the Vce of the common base transistor which is a good thing.

Increase the current sink, this lowers the impedance of the common base transistor

Use better transisors like 2SA970BL and 2SC2240BL


One thing I did this week was replacing the 2W (magnetic) carbon resistors is was using for Riv with some DALE RN60C's
I never bothered about resistors but this spot seems quite critical
A certain edge has gone and upper bass, lower mids improved a lot. Sounds much warmer without loosing detail.

If you're willing to do some tweaking, I would love to hear some feedback.
Could you let me know some of the voltages, currents and parts you are using, have set-up ?

After my vacations I'll implement the "not so very simple active I/V" which is DC coupled , uses better parts, has a lower impedance that the DAC will see, etc.

Will let y'all know the results of course
__________________
Rudolf Broertjes
  Reply With Quote
Old 9th July 2003, 09:22 AM   #5
diyAudio Member
 
Join Date: Jun 2003
Location: HK
Hi Rudolf,

Thanks for your advice.

I use 6V for the TDA1543 currently. And the I/V stage supply is around 14.2V (7808+6.2V zener), the base voltage of Q3 is around 3.3V (I use 3k3+1k5 for R7).

Will tweak this circuit and will let you all know the results.

Cheers
  Reply With Quote
Old 9th July 2003, 10:07 AM   #6
miguel2 is offline miguel2  Portugal
diyAudio Member
 
Join Date: Jun 2002
Location: Portugal
Is Rudolf's schematic available?

Miguel
  Reply With Quote
Old 9th July 2003, 01:43 PM   #7
diyAudio Member
 
Join Date: Nov 2002
Location: somewhere
yours seem better than mine..
Attached Images
File Type: jpg 1543.jpg (51.3 KB, 910 views)
  Reply With Quote
Old 9th July 2003, 07:43 PM   #8
diyAudio Member
 
Join Date: Jun 2003
Location: HK
Quote:
Originally posted by miguel2
Is Rudolf's schematic available?

Miguel

Simple ACTIVE I/V for TDA1543

Cheers
  Reply With Quote
Old 10th July 2003, 09:20 AM   #9
miguel2 is offline miguel2  Portugal
diyAudio Member
 
Join Date: Jun 2002
Location: Portugal
  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
Another GC is born! mantisory Chip Amps 10 6th July 2006 03:35 PM
One more DIY TT is born livemusic Analogue Source 18 20th December 2005 09:44 AM
New Aleph30 born mpopovics Pass Labs 4 15th July 2005 06:47 AM
new gain is born sith Chip Amps 9 4th October 2004 06:27 AM
A new Aleph3 is born... Smithers Pass Labs 9 10th January 2003 01:41 PM


New To Site? Need Help?

All times are GMT. The time now is 10:55 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