pquadrat said:
uploaded to my webspace, so everyone can enjoy the scematics
http://members.home.nl/brunsting/DAC.zip
pquadrat,
Do you have any comment on the sound of the d1 coupled with the PCM1704? Why did you choose not to follow Uli’s advice on upping the output of the d1 stage to normal levels? Can you use this dac with a passive preamp? Do the 610 mosfets get hot?
uli,
I have printed the value changes you’re recommending in red next to the old values in red. Can you confirm these values? Look at the value of c15, c16 the value change seems drastic.
Someone should get in touch with the mediator of this forum and tell them we want to post PDF files without having to zip them.
Leve
Do you have any comment on the sound of the d1 coupled with the PCM1704? Why did you choose not to follow Uli’s advice on upping the output of the d1 stage to normal levels? Can you use this dac with a passive preamp? Do the 610 mosfets get hot?
uli,
I have printed the value changes you’re recommending in red next to the old values in red. Can you confirm these values? Look at the value of c15, c16 the value change seems drastic.
Someone should get in touch with the mediator of this forum and tell them we want to post PDF files without having to zip them.
Leve
LBHajdu said:
I'm using the D1 wiith sony's current pulse dacs - parts of a cd player- instead of the cd player op amps. The output level is quite high and capable to drive the Zen, Aleph X .In fact , currently I 'm not using a preamplifier (active) thanks to the D1 . Of course the Aleph ono do not need the preamplifier too IMHO.
The 610 do not get hot , they are running *only* 10mA par side.
The sound of the inside op amps of the cd player is long way not comparable with the D1 I/V stage.
The D1 is better , much better .
Sorry if this reply is not directly based on a experience with the PCM1704 ,but i'm sure you can obtain good results even with it.
The game is worth the candle.
first of all, I made a parts list.
Things You should know:
The output capacitors are not on the board, You have to put them between
PCB output and Your output connectors. See D1 schematics.
The relay has no pins to connect to the coil. You have to solder wires on the reverse side of the pcb to the relay.
You have to cut one trace between the rectifier bridges. it is the only straight trace between D1 and D2 on AC side.
You have to solder one of the wires of the transformer to the cut-of pin of D2 then.
Because of incorrect information in one data sheet, You have to connect pin 10 to pin 4 (-5V) on U1 and U3. U1 and U3 are inverting the signal then, neccesary for balanced operation.
Feedback on this design is welcome, maybe I will do a second version later this Year. With error corrections and improvements, but basically the same concept.
-Peter
Things You should know:
The output capacitors are not on the board, You have to put them between
PCB output and Your output connectors. See D1 schematics.
The relay has no pins to connect to the coil. You have to solder wires on the reverse side of the pcb to the relay.
You have to cut one trace between the rectifier bridges. it is the only straight trace between D1 and D2 on AC side.
You have to solder one of the wires of the transformer to the cut-of pin of D2 then.
Because of incorrect information in one data sheet, You have to connect pin 10 to pin 4 (-5V) on U1 and U3. U1 and U3 are inverting the signal then, neccesary for balanced operation.
Feedback on this design is welcome, maybe I will do a second version later this Year. With error corrections and improvements, but basically the same concept.
-Peter
pquadrat said:
Hi Peter,
Would it be possible to produce a second batch of PCBs?
There must be at least another 10 people interested!
I, for myself, have long since dreamed of such a project with those highquality components...
Have you already listened to it?
Of course you should also earn a little on them...
Maybe?
Greetings,
Lucas.
peranders said:pquadrat, nice work
Is the pcb two layer or more?
I myself will update my DAC project but this is the future....sometime. The current CS4328 DAC is working very well but it would be cool to have the latest technology.
It's only two-sided. And only about 20 vias. I will try to make an improved version later this year, no time at the moment, and I would incorporate feedback from the users of this PCB version.
Abot the 1.2mA output current of the PCM1704: earlier in this thread are changed values for some resistors. If I remeber right, there are the values for 2mA output in the parts list. But I run my own DAC with these, and the output voltage is only slightly lower than normal. So You can try both.
And please post if You got it running !
-peter
Monster
Hi Peranders,
sure PCM1792?
There is nothing on TI´s page. As far as I know is
the PCM 1704 by far the best TI converter.
The Dc offset will be handled by the outputcaps
in peters design, in my version (which I am building
now with Peters board - thanks Peter) there is a
slightly different circuit, which doesnt need the caps.
Uli
peranders said:
Hi Peranders,
sure PCM1792?
There is nothing on TI´s page. As far as I know is
the PCM 1704 by far the best TI converter.
The Dc offset will be handled by the outputcaps
in peters design, in my version (which I am building
now with Peters board - thanks Peter) there is a
slightly different circuit, which doesnt need the caps.
Uli
As you guys know, the 7 boards that Peter printed out are long gone. However, he seems to be prone to doing a re-print in a short period of time if someone is willing to do the money collection and shipping.
As you can see there is another upsampler available or the AD1895 could be used instead. Some supposed minor bugs will be fixed, too. If there is enough interest I could handle the payment and distribution in the US, someone else would have to do Europe because it wouldn't make sense to have boards cross the atlantic ocean twice.
Please send me an email if you are interested.
Here is the letter he asked me to post:
Hello,
about the AD1896: Yes, it is out of production, but has been replaced
by the AD1896A. Same device, same specs, but minor bug fix. I got two
samples from Analog on request. Just to email the right people.
And if You have problems getting the 1896A, You can use the 1895,
which is available from AD's Web site as a sample, and is pin
compatible.
Just a little lower specifications. I assume the FIR filtering uses
less
prcision.
Yes, I can do a little rework of the board, not for an different
upsample,
as written above, but to fix some minor bugs (as written in the
forum).
If someone handles the individual shipping, I could even order the
boards from
the same manufacturer than the first run. Quality was very nice.
Its only the problem that I do not have time to handle all the
shipping
and payment work/trouble.
But I would like to get feedback from some of the seven buyers
on this board, to see if there is something to improve. Not the
"ususal"
hints of some members of the forum, but real fixes and improvements.
You can post this mail on the forum, I am very limited in time this
month.
Regads,
Peter
As you can see there is another upsampler available or the AD1895 could be used instead. Some supposed minor bugs will be fixed, too. If there is enough interest I could handle the payment and distribution in the US, someone else would have to do Europe because it wouldn't make sense to have boards cross the atlantic ocean twice.
Please send me an email if you are interested.
Here is the letter he asked me to post:
Hello,
about the AD1896: Yes, it is out of production, but has been replaced
by the AD1896A. Same device, same specs, but minor bug fix. I got two
samples from Analog on request. Just to email the right people.
And if You have problems getting the 1896A, You can use the 1895,
which is available from AD's Web site as a sample, and is pin
compatible.
Just a little lower specifications. I assume the FIR filtering uses
less
prcision.
Yes, I can do a little rework of the board, not for an different
upsample,
as written above, but to fix some minor bugs (as written in the
forum).
If someone handles the individual shipping, I could even order the
boards from
the same manufacturer than the first run. Quality was very nice.
Its only the problem that I do not have time to handle all the
shipping
and payment work/trouble.
But I would like to get feedback from some of the seven buyers
on this board, to see if there is something to improve. Not the
"ususal"
hints of some members of the forum, but real fixes and improvements.
You can post this mail on the forum, I am very limited in time this
month.
Regads,
Peter
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