Any good TDA1541A DAC kit? - Page 49 - diyAudio
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 9th January 2013, 02:35 AM   #481
diyAudio Member
 
Join Date: Oct 2009
Location: Brunei
Never mind...
__________________
--------
TDA1541a-S2 / 6072a / MediaplayerDac -- Michell Gyrodec -- Aikido Preamp -- Pass F5 -- Audio Physic Tempo 2SE -- Yamamura Cabling
  Reply With Quote
Old 9th January 2013, 07:44 AM   #482
diyAudio Member
 
Join Date: Apr 2008
Quote:
Originally Posted by vanofmonks View Post
Here is one based on Thorsten's 2005 schematic. The inductors are Panasonic with mu metal shields. To save board space, output capacitors are external of the board.
Well I will definitely be in on a group buy if necessary (including the tube output stage) very much looking forward to the finished product (hopefully Thorsten will not mind others using his output stage if asked nicely as it would be a great addition )

Good idea with the tube output capacitors as they can get very big depending on choice . I for one always have trouble getting those big ones to fit nice .

I have heard putting something like an LT1086 in front of the shunts makes them even quieter can anyone answer if this is true or not ?

Would it maybe be an idea making the on board capacitor diameters just a little larger ?
  Reply With Quote
Old 9th January 2013, 01:44 PM   #483
regal is offline regal  United States
diyAudio Member
 
Join Date: Jan 2004
Location: MD
Quote:
Originally Posted by paul_peraic View Post
Well I will definitely be in on a group buy if necessary (including the tube output stage) very much looking forward to the finished product (hopefully Thorsten will not mind others using his output stage if asked nicely as it would be a great addition )

Good idea with the tube output capacitors as they can get very big depending on choice . I for one always have trouble getting those big ones to fit nice .

I have heard putting something like an LT1086 in front of the shunts makes them even quieter can anyone answer if this is true or not ?

Would it maybe be an idea making the on board capacitor diameters just a little larger ?
You would want to use a DN2450 casode instead of a LT106 feeding the TL shunt. Much lower noise.

As far as this ube stage I see problems. The inductors are going to pickup lot of hum, the best inductors for this are air coil and they are big.

Thorten's tube I/V stage is much different now than this old design, he now uses a gnome stage:

http://www.diyaudio.com/forums/digit...pling-tda1541a

Designing a Gomes i/v stage for tda1541a

If one were to make a pcb it would make sense for a gnomes stage but for what is being proposed point to point is better, not many are fond of the 6922/6dj8 anyway with its high H3.

Also Oleg had a webpage that showed one needs to inject 2mA current to offset the TDA1541's dc offset at the top of the i/V resistor, same as what Pedra Rohic does.
  Reply With Quote
Old 10th January 2013, 01:12 AM   #484
diyAudio Member
 
Join Date: Oct 2009
Location: Brunei
Quote:
Originally Posted by regal View Post
You would want to use a DN2450 casode instead of a LT106 feeding the TL shunt. Much lower noise.

As far as this ube stage I see problems. The inductors are going to pickup lot of hum, the best inductors for this are air coil and they are big.

Thorten's tube I/V stage is much different now than this old design, he now uses a gnome stage:

http://www.diyaudio.com/forums/digit...pling-tda1541a

Designing a Gomes i/v stage for tda1541a

If one were to make a pcb it would make sense for a gnomes stage but for what is being proposed point to point is better, not many are fond of the 6922/6dj8 anyway with its high H3.

Also Oleg had a webpage that showed one needs to inject 2mA current to offset the TDA1541's dc offset at the top of the i/V resistor, same as what Pedra Rohic does.
I am using the Gomes stage in my dac, and it sounds excellent. One thing about the 2ma offset: i am using the negative offset as fixed bias to be able to bias the tubes very near to their 0v line (while surely maintaining a negative bias). So not in all cases it's useful to compensate the offset.
__________________
--------
TDA1541a-S2 / 6072a / MediaplayerDac -- Michell Gyrodec -- Aikido Preamp -- Pass F5 -- Audio Physic Tempo 2SE -- Yamamura Cabling
  Reply With Quote
Old 10th January 2013, 01:23 AM   #485
diyAudio Member
 
Join Date: Apr 2008
Quote:
Originally Posted by regal View Post
You would want to use a DN2450 casode instead of a LT106 feeding the TL shunt. Much lower noise.

As far as this ube stage I see problems. The inductors are going to pickup lot of hum, the best inductors for this are air coil and they are big.

Thorten's tube I/V stage is much different now than this old design, he now uses a gnome stage:

http://www.diyaudio.com/forums/digit...pling-tda1541a

Designing a Gomes i/v stage for tda1541a

If one were to make a pcb it would make sense for a gnomes stage but for what is being proposed point to point is better, not many are fond of the 6922/6dj8 anyway with its high H3.

Also Oleg had a webpage that showed one needs to inject 2mA current to offset the TDA1541's dc offset at the top of the i/V resistor, same as what Pedra Rohic does.
So then what would be an alternative that is as readily available and as affordable as the 6922/6DJ8/6N23P/6N1P ?

Last edited by paul_peraic; 10th January 2013 at 01:30 AM.
  Reply With Quote
Old 10th January 2013, 01:32 AM   #486
diyAudio Member
 
Join Date: Apr 2008
Quote:
Originally Posted by studiostevus View Post
I am using the Gomes stage in my dac, and it sounds excellent. One thing about the 2ma offset: i am using the negative offset as fixed bias to be able to bias the tubes very near to their 0v line (while surely maintaining a negative bias). So not in all cases it's useful to compensate the offset.
Are there any purchasable boards available for this ?
  Reply With Quote
Old 10th January 2013, 02:43 AM   #487
diyAudio Member
 
Join Date: Oct 2009
Location: Brunei
Quote:
Originally Posted by paul_peraic View Post
Are there any purchasable boards available for this ?
Nope. The circuit is so simple that p2p is the best option here
__________________
--------
TDA1541a-S2 / 6072a / MediaplayerDac -- Michell Gyrodec -- Aikido Preamp -- Pass F5 -- Audio Physic Tempo 2SE -- Yamamura Cabling
  Reply With Quote
Old 10th January 2013, 03:04 AM   #488
diyAudio Member
 
Join Date: Apr 2008
Quote:
Originally Posted by studiostevus View Post
Nope. The circuit is so simple that p2p is the best option here
OK yeah point to point does sound nice where can I get a schematic
  Reply With Quote
Old 10th January 2013, 02:59 PM   #489
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Quote:
Originally Posted by studiostevus View Post
I am using the Gomes stage in my dac, and it sounds excellent.
Can you please post a schematic of it?
  Reply With Quote
Old 10th January 2013, 06:13 PM   #490
diyAudio Member
 
Join Date: Jun 2003
Location: Hamilton, was Ottawa (Canada)
Quote:
Originally Posted by s3tup View Post
Feeding back the bitclock/masterclock/other sync signal to the soundcard is easy, as long as your soundcard supports it.

There are really cheap Envy24-based cards, with Tremor chipset - they go for 5-10$ a card, have tappable i2s lines, and onboard xtals for 44100 and 48000 sampling rates.
You can take the 44100 xtal from the board, throw it on the dac board + reclock the i2s lines with it. Then you feed the Tremor with that clock directly.

Easy, cheap, and you can withdraw all the SPDIF conversions all together, by throwing-in RS485 transceivers on both ends of transmission line.
You get slight ground break, DAC-sourced clock, and no SPDIF.
In the other hand, you get PC-only DAC. High quality soundcard, that's it.


You can use any soundcard, which have SPDIF input, and which is able to lock on external SPDIF, and sync-up with it.
Then you use reclocker/clock distributor on DAC side, and feed the soundcard back with a sync signal in the SPDIF envelope.

SPDIF has simple square wave signal for digital "0", with 64fs rate. You can form it by passig the MCLK thru 1/4 divider + transformer.

Third, but not last solution - is to use Infrasonic Quartet soundcard, which can thake 128fs/256fs sync signal directly, bypassing the spdif thing. It has BNC connectors for masterclock in/out.

All you need to do to eliminate the jitter, is to clock the DAC with local fixed clock (no VCOs), and control the incoming data flow by feeding back the clock to digital source.

You need, as stated several times above, to badwidth-limit the data lines going to the TDA. Attenuation would be nice too.
You'll need to do this on the I2S source end, so the HF signal edges would be passed by BW-limiting capacitors back to the I2S source ground, not the DAC's ground.
Hey s3tup, can you give some examples of these cards? I did a quick search and didn't see any easy I2S.

Thanks,
Jeff
  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
Raindrop Hui TDA1541A DAC Kit wushuliu Swap Meet 25 21st November 2013 10:07 AM
which clock for analogmetric tda1541A dac kit Chilli6565 Digital Source 4 6th May 2010 12:41 PM
FS: AYA DAC Rev 2.0b TDA1541A Non-Oversampling DAC kit or complete krishu Swap Meet 0 17th December 2009 09:33 AM
Recommend a DIY tda1541a dac kit? boidos Digital Line Level 2 6th August 2009 01:43 PM
TDA1541A Chineese DAC KIT UV101 Digital Source 8 10th February 2009 10:46 AM


New To Site? Need Help?

All times are GMT. The time now is 06:38 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