Go Back   Home > Forums > > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Vendor's Bazaar Commercial Vendors large & small hawking their wares

Output transformers for DACs
Output transformers for DACs
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 20th November 2019, 03:38 PM   #321
yunyun is offline yunyun
Sin Bin
 
Join Date: Jun 2019
Quote:
Originally Posted by bisesik View Post
The real measured inductance (2-3 years after its manufacturing I think) of this EI (marked as 430H on photo) transformer is ~180H now at 100Hz. So the answer to your question pretty simple: difference in inductances are due to different plates permability within different transformers and due to wiring differences within one transformer (a bit less\more resistance), which are escalated over the time. To be honest the difference in pair of transformers even within 5-10% is a very good result as in the real transformer (not in theoretical, but in real) there is no inductive resistance only. Transformer is very complex thing and it is simply not possible to rely all the things needed for sound\music on inductances only, especcially at 100Hz only. But I believe the point is not that the object was old or new or in their absolute values of inductances. I believe mentioned transformers are still very good in terms of quality\cost. The more inductance you can get on the same dimmensions\wiring - the better perfomance - no questions. With hope that benefits (permability) will not go down over the time significally...



Sure they can measure at any frequency, but this particular measurement showned on photo (declared in specs) done at 100Hz.

The really interesting\sensitive things happens in another aspects of transformers. Seems that such regular (EI thick plate based) transformers simply stops to be transformers at higher frequencies if they have such a big amount of inductance\wire length, because the capacitive resistances between coils becames dominant over others. Transformer becomes... becomes... becomes capacitor

And if takes into account that 1:1 transformers are poorly suitable with current-type DACs (I believe DSC works better in current-output mode, similar to ES90x8 btw), and taking into account that step-up transformers works as LPF what is higly needed for DACs (Delta-sigma\SDM output especcially, remember Rasmussen filtering ) - things becomes clearer a bit.

I know why this approach poorly works on other step-up transformers and clearly understand why people prefer 10k:10k over 600:10k of the same-type transformer, but it is another storry...

Clearer just "a bit" - because measurements very often are going in parallel or even in wrong direction when you comes closer and closer to the music in opposite to sound.

yunyun, I suggest to make the necessary comparative measurements from someone else, but AFTER real comparative listening within system that have no limit after DAC in terms of quality of following components. Reading your posts, I understand that I will always stays too interested person in this thread to to satisfy your curiosity
I can't fully agree with you said what the more inductance you can get on the same dimmensions\wiring - the better perfomance - no questions.

The higher the inductance will get the better the low-frequency signal but the high-frequency will be worse. That is to say that the inductance of the transformer is not a pursuit of higher inductance, and it needs to be balanced in many aspects. Lundahl's transformer is designed to pay attention to high-frequency transparency, but the low-frequency listening is thin.

I hope that you can complete the PCB for your transformer as soon as possible, otherwise I will difficulty use it to do real comparative listening.

Last edited by yunyun; 20th November 2019 at 04:04 PM.
  Reply With Quote
Old 20th November 2019, 04:55 PM   #322
sq225917 is offline sq225917  United Kingdom
diyAudio Member
 
Join Date: Jun 2004
Location: sheffield
Send a message via MSN to sq225917 Output transformers for DACs
If you look under the bridge today.....
  Reply With Quote
Old 20th November 2019, 08:24 PM   #323
misterdog is offline misterdog  United Kingdom
diyAudio Member
 
Join Date: Dec 2011
Location: Sheffield
Will it be flooded ?
  Reply With Quote
Old 21st November 2019, 12:34 AM   #324
sumotan is offline sumotan  Indonesia
diyAudio Member
 
Join Date: Oct 2013
Quote:
Originally Posted by bisesik View Post
Hi sumotan. Very good question! Yes, TDA1541 is very musical DAC, but it has some dificulties.
Previously I have used transformers with special DC-offset coil. But the price for such transformer looks a bit too costly compared to right-implemented regular transformer without special offset-coil. The difference between both approaches in THD measurements mainly was below 150Hz and was not very much (at least not 10 times less with offset coil as I remember - it was really not very hearable). And if taking into accout that DIYers mostly can not \ not want to make deal with additional complexity (extra PSU with needed voltage) during connectivity... I decided to provide simple one primary coil solution only (between Iout and gnd).
Anyway I think it is better to ask Dubai2000 about his experience with my transformers for TDA1541.
But time to time I am still wondering if it is possible to avoid dc-offset if to use 1541 in balanced mode (2x1541)?.. with simple connection of primary coil between Iout+ and Iout- with coil's CT at GND?.. But the demand for 1541 in our days is not high enough to allow me spend time for such experiments now, sorry ...
Thank you kindly for the reply .

Cheers
  Reply With Quote
Old 26th November 2019, 02:01 PM   #325
bisesik is online now bisesik  Kazakhstan
Output transformers for DACs
diyAudio Member
 
Join Date: Sep 2008
Location: Kazakhstan, Almaty
Output transformers for DACs
Here is how transformer in new design looks like in real:

mill-maxx_version.jpg
  Reply With Quote
Old 26th November 2019, 02:01 PM   #326
ilgavro is offline ilgavro
diyAudio Member
 
Join Date: Sep 2018
Nice
  Reply With Quote
Old 26th November 2019, 03:24 PM   #327
misterdog is offline misterdog  United Kingdom
diyAudio Member
 
Join Date: Dec 2011
Location: Sheffield
  Reply With Quote
Old 27th November 2019, 01:30 AM   #328
clay-speakers is offline clay-speakers  Australia
diyAudio Member
 
Join Date: Aug 2006
Location: Gold Coast, Australia
Awesum!
  Reply With Quote
Old 27th November 2019, 11:14 AM   #329
bisesik is online now bisesik  Kazakhstan
Output transformers for DACs
diyAudio Member
 
Join Date: Sep 2008
Location: Kazakhstan, Almaty
Output transformers for DACs
DSC.jpg
DSC2.jpg
This "DSC" i/v board can be considered as some of universal type for different DACs based on my transformers. For the prototype was taken a printed circuit board from Pavel (ppy). Genuine RCAs on it are really very well manufactured. Сosty compared to other PCBs because of more expensive parts used on it. But I believe the components on it are the same now with that which are used many hi-end audio manufacturers.
The price for assembled PCB including receptacles (really costy parts) and genuine RCAs\XLRs even without transformers will be more than 100$. How much exactly - do not want to calculate without real demand
  Reply With Quote
Old 27th November 2019, 03:56 PM   #330
lemon is offline lemon  Greece
diyAudio Member
 
Join Date: Apr 2009
Bisesik,
What type of Pin Receptacles are they on the pcb?
  Reply With Quote

Reply


Output transformers for DACsHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
PC based I2S Output for compatible DACs Vortex Digital Line Level 1 5th May 2018 08:37 PM
Zapfilter2 and current-output dacs Glenn2 Digital Line Level 5 31st October 2016 08:36 AM
D2A aragon dac with blowed output stage after the dacs... inertial Solid State 0 8th July 2013 05:04 PM
Differential output DACs, can I use only one output. oon_the_kid Digital Line Level 14 4th July 2011 03:09 AM
any info. anywhere on output stages for dacs? lt cdr data Digital Source 3 21st May 2005 05:18 AM


New To Site? Need Help?

All times are GMT. The time now is 03:41 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki