Hi all,
yesterday I connected the DEM reclocking into my non-os DAC (basically TNT design with improved dynamics). It is the simplest scheme of ecdesigns, i.e. BCK -> 74HC161 -> capacitor -> TDA1541. I must say I'm disapointed. Yes, the bass is slightly better defined, electric guitars more aggressive, but thats all of good. No veil over music removed, on the contrary: it sounds somehow stressed, vocals more laid back. The sound is somehow monolithic, I'd say, as if the harmonics are truncated, less air. The feeling reminds me as if there is slight hum in the system -- you actualy hear nothing, but feel more comfortable if it is switched off.
Given the very positive impressions here, I think my implementation may be wrong. I used M74HC161. The SCK from cs8412 is connected via 1k resistor to TDA as before. The SCK to 74HC161 is taken directly from cs8412 before the 1k resistor and without any resistor. The capacitor is the original one, 470pF.
I give the TDA some time to burn in, but most likely return to the simple capacitor solution. I appreciate any ideas. By the way, at which frequency runs the DEM only with 470pF capacitor?
Petr
yesterday I connected the DEM reclocking into my non-os DAC (basically TNT design with improved dynamics). It is the simplest scheme of ecdesigns, i.e. BCK -> 74HC161 -> capacitor -> TDA1541. I must say I'm disapointed. Yes, the bass is slightly better defined, electric guitars more aggressive, but thats all of good. No veil over music removed, on the contrary: it sounds somehow stressed, vocals more laid back. The sound is somehow monolithic, I'd say, as if the harmonics are truncated, less air. The feeling reminds me as if there is slight hum in the system -- you actualy hear nothing, but feel more comfortable if it is switched off.
Given the very positive impressions here, I think my implementation may be wrong. I used M74HC161. The SCK from cs8412 is connected via 1k resistor to TDA as before. The SCK to 74HC161 is taken directly from cs8412 before the 1k resistor and without any resistor. The capacitor is the original one, 470pF.
I give the TDA some time to burn in, but most likely return to the simple capacitor solution. I appreciate any ideas. By the way, at which frequency runs the DEM only with 470pF capacitor?
Petr
Hello
Anybody know how to do a differential DEM clock (create both inverted and non-inverted 352.8 KHz signal) for a non-os 1541 dac ?
Today a friend sent me an email to told me that he read that this way was better, but he do not know how to do it and I would like to do it.
Thank
Bye
Gaetan
Anybody know how to do a differential DEM clock (create both inverted and non-inverted 352.8 KHz signal) for a non-os 1541 dac ?
Today a friend sent me an email to told me that he read that this way was better, but he do not know how to do it and I would like to do it.
Thank
Bye
Gaetan
tubee said:
Hello
The only DEM clock I founded on the thread are not a differential DEM clock with an inverted and non-inverted 352.8 KHz signal.
How can I modify it to be a differential DEM clock ?
Here the link to the message and also to the image;
http://www.diyaudio.com/forums/showthread.php?postid=918503#post918503
http://www.diyaudio.com/forums/attachment.php?s=&postid=918503&stamp=1147880942
Thank
Gaetan
More on the end of the huge thread.
http://www.diyaudio.com/forums/showthread.php?postid=1660547#post1660547
(Nice amp you have gaetan😀 )
http://www.diyaudio.com/forums/showthread.php?postid=1660547#post1660547
An externally hosted image should be here but it was not working when we last tested it.
(Nice amp you have gaetan😀 )
_ecdesigns_ mentioned somewhere a DEM clocking solution with coupling transformer. This looks like a nice idea, the DEM input pins may be floating with respect to ground.
That was someone else (onnosr) who suggested it to EC. With the coupling caps it floates to gnd too. Will listen to the 880 tonight and post sound results.
hey tubee,can you post the exact schematics with the circuits that you have used to obtain the 352khz and also the inverted 352khz?
i would need a pin to pin schematic and the IC's used
(also if you have derived that from masterclock or bck)
Much appreciated,thanks!
i would need a pin to pin schematic and the IC's used
(also if you have derived that from masterclock or bck)
Much appreciated,thanks!
Sorry If I divert a little bit here.
I am using TDA 1541A, with input using DV709 to CS8412-CS. The clock is 11.2896 TCX and feeding 74HC4040 and SAA7220 filters. Saa7220 feeds TDA 1541A in 16bit 8times OS. Output IV is by 2 stages of NE 5534 (total 4 units) before going to the coupling cap of 10uF (Jantzen cross cap).
Can I know if the 8 times OS is better replaced by NOS? and How to convert to NOS ?
I am using TDA 1541A, with input using DV709 to CS8412-CS. The clock is 11.2896 TCX and feeding 74HC4040 and SAA7220 filters. Saa7220 feeds TDA 1541A in 16bit 8times OS. Output IV is by 2 stages of NE 5534 (total 4 units) before going to the coupling cap of 10uF (Jantzen cross cap).
Can I know if the 8 times OS is better replaced by NOS? and How to convert to NOS ?
Will post it when i have some time ok?
First try a good master clock (tent XO or Kwak)
Dem in short it's this:
11.2896 to 74HCT163, /8 output to another 163, /4 gives 352kHz gives pos dem signal to pin 16 with attenuator and coupling cap (NP0 SMD chip capacitor)
The pos dem signal goes also into an inverter 74HCT04 for inverted dem to pin 17 as on my schematic.
I use the same first 163 counter for /2 clock reclock of 5,6 Mhz into tda1541, and in non-os it has to be /4 (2.8Mhz)
Will show pic soon.
First try a good master clock (tent XO or Kwak)
Dem in short it's this:
11.2896 to 74HCT163, /8 output to another 163, /4 gives 352kHz gives pos dem signal to pin 16 with attenuator and coupling cap (NP0 SMD chip capacitor)
The pos dem signal goes also into an inverter 74HCT04 for inverted dem to pin 17 as on my schematic.
I use the same first 163 counter for /2 clock reclock of 5,6 Mhz into tda1541, and in non-os it has to be /4 (2.8Mhz)
Will show pic soon.
Tubee,
What advantage is gained by operating the DAC chip at 2.8M? And would it be necessary to clean up the accumulated jitter by reclocking it to the master clock?
What advantage is gained by operating the DAC chip at 2.8M? And would it be necessary to clean up the accumulated jitter by reclocking it to the master clock?
The clock output from SAA7220 is rather unclean yes.
I use a master 11Mhz clock and derive there all other freq. from
I use a master 11Mhz clock and derive there all other freq. from
Finally, made a drawing to dem reclock a 1541. Have fun with it. Remind: all the credits goes to ECdesigns!
How i did it:
Added 2 counters and an inverter on the Kwak pcb
An externally hosted image should be here but it was not working when we last tested it.
How i did it:
An externally hosted image should be here but it was not working when we last tested it.
Added 2 counters and an inverter on the Kwak pcb
thank you for tour time and the nice drawing you made 🙂
one question for the drawing :
on the TDA chip i believe that instead of pin1 you wanted to say pin 2+4 (BCK and SCK) for the clock divided by 2 in 4xOS mode
corect me if i'm wrong
one question for the drawing :
on the TDA chip i believe that instead of pin1 you wanted to say pin 2+4 (BCK and SCK) for the clock divided by 2 in 4xOS mode
corect me if i'm wrong
You are right 😉 connect clk to dac as it was. Some dacs have only pin 2, some pin 2 and 4.
When you bypass the dig filter and non-os take /4 divider from first counter to dac. 2.8Mhz is clock to dac in non-os
And the 47 ohm resistor before the 1k2 must be to the gate of the 74/04 😉 😉
When you bypass the dig filter and non-os take /4 divider from first counter to dac. 2.8Mhz is clock to dac in non-os
And the 47 ohm resistor before the 1k2 must be to the gate of the 74/04 😉 😉
Hi Tubee,
I have a question. below is my TDA 1541 which I already mod to NOS by removing the SAA7220 and bypass. Now that I am using the 74HC4040 for the counter, can I use it instead of the 74HCT163.
What is NPO 1nF, is it a film cap? any brand recommended ? For the 1k2, can I just use normal 1% resistor or it must be Dale resistor ?
I have a question. below is my TDA 1541 which I already mod to NOS by removing the SAA7220 and bypass. Now that I am using the 74HC4040 for the counter, can I use it instead of the 74HCT163.
What is NPO 1nF, is it a film cap? any brand recommended ? For the 1k2, can I just use normal 1% resistor or it must be Dale resistor ?
The 4040 is some faster as the 163 and could be some better then. I guess it will work when i see the schematic. Try to reclock 1541 with 2.8Mhz too with it.
I have 163 run in continous mode. The 4040 should be run in the same way.
The NP 'zero' 😉 is an ceramic SMD cap
http://en.wikipedia.org/wiki/EIA_Class_1_dielectric
The resistor is a regular metal film but experiments are welcome🙂
I have 163 run in continous mode. The 4040 should be run in the same way.
The NP 'zero' 😉 is an ceramic SMD cap
http://en.wikipedia.org/wiki/EIA_Class_1_dielectric
The resistor is a regular metal film but experiments are welcome🙂
i also ordered this dac kit from hongkong,but here you have 1 more "problem" to solve...
this kit comes as 8x oversampling in stock form - sa7220 does the 4x and the 74hc4040 does the 2x !
so it is not enough to bypass the sa7220 for NOS,you also have to take BCK and FS from pins Q2 and Q8 instead of Q1 and Q7.
follow the way it divides the clock with the 11.2896 mhz:
Q1 - 5,64 MHZ
Q2 - 2,82 MHZ (BCK)
Q3 - 1,4 MHZ
Q4 - 0.7 MHZ
Q5 - 350 KHZ (for DEM reclock)
Q6 - 175 KHZ
07 - 87.5 KHZ
Q8 - 44 KHZ (FS)
also Q5 is 350khz suitable for DEM reclocking,with an inverter attached of course
happy moding and please tell us your listening impressions after the real NOS moding
this kit comes as 8x oversampling in stock form - sa7220 does the 4x and the 74hc4040 does the 2x !
so it is not enough to bypass the sa7220 for NOS,you also have to take BCK and FS from pins Q2 and Q8 instead of Q1 and Q7.
follow the way it divides the clock with the 11.2896 mhz:
Q1 - 5,64 MHZ
Q2 - 2,82 MHZ (BCK)
Q3 - 1,4 MHZ
Q4 - 0.7 MHZ
Q5 - 350 KHZ (for DEM reclock)
Q6 - 175 KHZ
07 - 87.5 KHZ
Q8 - 44 KHZ (FS)
also Q5 is 350khz suitable for DEM reclocking,with an inverter attached of course
happy moding and please tell us your listening impressions after the real NOS moding
So I guess instead of NOS I am running at 2 times oversampling which is 5.6 MHz and 87.5kHz. It seems the TDA 1541 is able to recognise the 2 times oversampling ???
1. If I understand you correctly, U1 pin 6 (= Q2 2.82MHz) connect to U6 pin2 (that means U4 pin 12 stay connected ?).
2. and then U1 pin 12 connect to U6 pin 1 (that means U4 pin 11 stay connected ??)
3. and what is the best way to connect ? Is it cut the trace at U1 Q1 and Q7 using a knife or do I just bend the leg outside the socket?
I am very clumsy at handling the SMT. Therefore I prefer to use thru hole
For the product I bought from Hong Kong, I was not happy with the way they handle the customer. They are not bothered with customer service. Good luck for your items.
I have basically replaced all the ceramic cap with WIMA cap.
1. If I understand you correctly, U1 pin 6 (= Q2 2.82MHz) connect to U6 pin2 (that means U4 pin 12 stay connected ?).
2. and then U1 pin 12 connect to U6 pin 1 (that means U4 pin 11 stay connected ??)
3. and what is the best way to connect ? Is it cut the trace at U1 Q1 and Q7 using a knife or do I just bend the leg outside the socket?
I am very clumsy at handling the SMT. Therefore I prefer to use thru hole
For the product I bought from Hong Kong, I was not happy with the way they handle the customer. They are not bothered with customer service. Good luck for your items.
I have basically replaced all the ceramic cap with WIMA cap.