Does it matter which of the decks you use in the two-deck configuration? If yes, then I'd take a closer look at those decks that cause problems. If not, I'd look at the 1/2 clock delay.
Some more questions (just to double check):
- What is the current draw by each deck?
- Your digital voltage is 5.0 V, not 3.3 V, correct?
- You removed R7 (1kOhm) from all the DAC boards and replaced it by a 100 Ohm resistor, correct?
- You double and triple checked the connections of the 1/2 clock delay board to the mainboard, and your double and triple checked your cuts of the traces on the mainboard, right?
Do you have a scope to look at the digital signals? Would be interesting to see if there are any differences between the 2-deck and 3/4-deck configurations.
Hello James,
This will be my first dddac. Already knew since building some of my other gear that i wanted to use choke input power supply with big R core transformer.
I did wait because i did not want to mutilate the boards with additional shunts boards.
Now thinking about using or not using the pre regulator. Because using choke input and another choke further down the line i think most of the garbage has gone.
Did go for the Sowther because they seem to be the best.
greetings, eduard
This will be my first dddac. Already knew since building some of my other gear that i wanted to use choke input power supply with big R core transformer.
I did wait because i did not want to mutilate the boards with additional shunts boards.
Now thinking about using or not using the pre regulator. Because using choke input and another choke further down the line i think most of the garbage has gone.
Did go for the Sowther because they seem to be the best.
greetings, eduard
- it doesn´t matter which decks i use: when using 2 decks everything is okay
- current draw of each deck: i didn´t messure
- digital volume is 4.9 V
- R7 is replaced with 100 ohm
- i don´t have a scope :-(
- the 1/2 clock delay: i have to check again, maybe remove it
thanks, mario
TX2575 and os con
Hello,
Did read a bit about the Rload resistors for my 4 board dac. Vishay data sheet says they are 0,4 watt at 70 degrees celsius. Partsconnexion list them as 0,6 watt because ambient temp will probably never be that high.
PPM is 0,2 . Price is 16$ a piece. I could go for single 33 ohm or two 68 ohm in parallel.
The partlist of the old dac board changed from 22* 47mf into 12 *10 and 2*47 mf. I did use some og the caps i bought for the DDDAC in my other gear. My usual supplier has stock of 22mF 25 volts silmic2 so i will get a few of them.
Partsconnexion has sanyo os con. lowest value is 180mf 16 volt will stock them too.
greetings, Eduard
P.s will probably skip the lf7810 at the entrance of the 8 volt shunt and see if it will be possible to give the lf33 its own '' supply line '' coming from the LCLC network with its own choke and cap just taking care of the other voltages needed.
Hello,
Did read a bit about the Rload resistors for my 4 board dac. Vishay data sheet says they are 0,4 watt at 70 degrees celsius. Partsconnexion list them as 0,6 watt because ambient temp will probably never be that high.
PPM is 0,2 . Price is 16$ a piece. I could go for single 33 ohm or two 68 ohm in parallel.
The partlist of the old dac board changed from 22* 47mf into 12 *10 and 2*47 mf. I did use some og the caps i bought for the DDDAC in my other gear. My usual supplier has stock of 22mF 25 volts silmic2 so i will get a few of them.
Partsconnexion has sanyo os con. lowest value is 180mf 16 volt will stock them too.
greetings, Eduard
P.s will probably skip the lf7810 at the entrance of the 8 volt shunt and see if it will be possible to give the lf33 its own '' supply line '' coming from the LCLC network with its own choke and cap just taking care of the other voltages needed.
I did some quick test with and without the 7810 pre regulation, as it so simple to check... Technically no issue, works fine with and without. Sound wise, well I really needed to go back and forward several times with some good live recordings to notice a very small difference in detail in background stage of the recording in favor of pre recording. To be honest, I am sure I would not be able to tell when it was blind and I walk in next morning if you know what I mean. Any way the pre regulation stays where it is in my DAC, not only because it sounds "minimally better" but for all, it buffers the shunt from any wild voltages and other unknown stuf you never know ( as a designer) that will or might be connected to the DAC.... And thermally it also has advantages.
But this hobby and DIY , so feel free to try and decide for yourself
Still, sounds incredibly good ... Still listening as I write this.
By the way did I ever mention, that the Aurender N100 media player I am using is another MAJOR part of the sound improvements I made recently? Unfortunately costs a bit
But this hobby and DIY , so feel free to try and decide for yourself
Still, sounds incredibly good ... Still listening as I write this.
By the way did I ever mention, that the Aurender N100 media player I am using is another MAJOR part of the sound improvements I made recently? Unfortunately costs a bit
Hi Doede,
My name is Oleg
Apologize for the off topic, but the messages to you are not delivered
I have got your dddac tda 1541a apparently built by you based on the casing which is similar to the pictures on your web site
It uses battery 12v supply I was thinking whether I could feed it with a regulated psu. You should have built one for comparison with pcm dddac before, but I recall it was 7A which is considerably high
Which psu would you recommend to feed the TDA1541a dddac ?
Thanks,
Oleg
Sent from my ONE A2003 using Tapatalk
My name is Oleg
Apologize for the off topic, but the messages to you are not delivered
I have got your dddac tda 1541a apparently built by you based on the casing which is similar to the pictures on your web site
It uses battery 12v supply I was thinking whether I could feed it with a regulated psu. You should have built one for comparison with pcm dddac before, but I recall it was 7A which is considerably high
Which psu would you recommend to feed the TDA1541a dddac ?
Thanks,
Oleg
Sent from my ONE A2003 using Tapatalk
Hi Doede,
My name is Oleg
Apologize for the off topic, but the messages to you are not delivered
I have got your dddac tda 1541a apparently built by you based on the casing which is similar to the pictures on your web site
It uses battery 12v supply I was thinking whether I could feed it with a regulated psu. You should have built one for comparison with pcm dddac before, but I recall it was 7A which is considerably high
Which psu would you recommend to feed the TDA1541a dddac ?
Thanks,
Oleg
Sent from my ONE A2003 using Tapatalk
sorry there is no such thing as a 1541 dddac... may be it is a 1543 dddac?
this is really off topic, so please send me an email at mail@doede.de
thanks
doede
Hello Doede,
I remember the messages from i think supersurfer about taking out the pre regulator..
But he was the one who also did connect the Lundahl chokes the wrong way lol.
I know from other projects no matter how good the series or parallel regulation changes made in the circuit prior to regulation will always be noticed.
Once everything is mounted with 4 boards it is a hell of a job to make change.
The R load resistors can be changed easily if i will make soldering side of the board easy accesible like in this picture of my home cinema 2.1 amp
greetings, Eduard
I remember the messages from i think supersurfer about taking out the pre regulator..
But he was the one who also did connect the Lundahl chokes the wrong way lol.
I know from other projects no matter how good the series or parallel regulation changes made in the circuit prior to regulation will always be noticed.
Once everything is mounted with 4 boards it is a hell of a job to make change.
The R load resistors can be changed easily if i will make soldering side of the board easy accesible like in this picture of my home cinema 2.1 amp
greetings, Eduard
Attachments
in the end it seems to be a bad soldering on the shunt for the 5V. never thought that bad soldering could be so hard to find and do so bad things :-(
now it´s time to listen again
thank you all for your help! mario
Hello,
Doede's Sowthers are in transit. Did order Shinkoh 2 watt as R load in the UK. Some Elna silmic 2 but still need about 10 10or 22 microfarad 16/25 or 35 volts os con caps. On ebay i did only see higher capacity on ebay which might not work at the output of some voltage stab transistors.
Where can i buy these in Europe or has anyone here has some surplus.
Just send me a message.
Thanksalot in advance, Eduard
Doede's Sowthers are in transit. Did order Shinkoh 2 watt as R load in the UK. Some Elna silmic 2 but still need about 10 10or 22 microfarad 16/25 or 35 volts os con caps. On ebay i did only see higher capacity on ebay which might not work at the output of some voltage stab transistors.
Where can i buy these in Europe or has anyone here has some surplus.
Just send me a message.
Thanksalot in advance, Eduard
in the end it seems to be a bad soldering on the shunt for the 5V. never thought that bad soldering could be so hard to find and do so bad things :-(
now it´s time to listen again
thank you all for your help! mario
Pleased you have found the problem - enjoy listening
Hello,
Did order the Os con at mouser,
No news on the boards eventhough i live in the same country as audio creative.
All the other parts are allready in transit.
Probably there are people in Vietnam who wanna listen to the dddac. Mine will be to heavy and to big to take all around South East Asia on my next trip. Maybe get some boards and ask them to prepare a big 12 volt supply.
This is one of the systems i will visit.
Already did ask Doede but one of my Vietnamese friend wants to know if using the special Sowther will make skipping a pre amplifier possible if the power amp will be used with some extra parts. Maybe transformer volume control by SaC in Thailand.
greetings, Eduard
Did order the Os con at mouser,
No news on the boards eventhough i live in the same country as audio creative.
All the other parts are allready in transit.
Probably there are people in Vietnam who wanna listen to the dddac. Mine will be to heavy and to big to take all around South East Asia on my next trip. Maybe get some boards and ask them to prepare a big 12 volt supply.
This is one of the systems i will visit.
Already did ask Doede but one of my Vietnamese friend wants to know if using the special Sowther will make skipping a pre amplifier possible if the power amp will be used with some extra parts. Maybe transformer volume control by SaC in Thailand.
greetings, Eduard
Attachments
just curious
Hello,
Just wondering if there are any customers who did already receive their boards. Buyers so far are first time buyers ( like me) or did they buy to replace their heavily diy modified circuit boards? Lots of the ''heavy posters'' seem to have gone.
Anyone has a nice stock of 100nF Kemet pps caps to try instead of the Wima. I forgot to include them in my Mouser order and they charge 20 euro '' ordering cost ''.
Greetings, Eduard
Hello,
Just wondering if there are any customers who did already receive their boards. Buyers so far are first time buyers ( like me) or did they buy to replace their heavily diy modified circuit boards? Lots of the ''heavy posters'' seem to have gone.
Anyone has a nice stock of 100nF Kemet pps caps to try instead of the Wima. I forgot to include them in my Mouser order and they charge 20 euro '' ordering cost ''.
Greetings, Eduard
Hello everyone, I am back with my fault finding mission. I have replaced the original I/V filters with four 68R as I have two boards but this hasn't improved the fault, still only getting 1.28v 1.317ohm from the rload and still getting very low volumes. What is the next step for fault finding?
Thanks in advance
Thanks in advance
@eduard
No, you need 1 resistor per current output.
2 channels * 2 current output (each channel have 2 current outputs, one is inverted or "balanced")
So you need at least 4 resitors on your main board.
(There are 8 slots on the main board, if you need to parallelize some resistors, Ra and Rb, to get the right value)
No, you need 1 resistor per current output.
2 channels * 2 current output (each channel have 2 current outputs, one is inverted or "balanced")
So you need at least 4 resitors on your main board.
(There are 8 slots on the main board, if you need to parallelize some resistors, Ra and Rb, to get the right value)