To a certain extent. My comments were made by simply swapping trafos(same system/same DAC configuration, etc) I also A/Bed the sound I got with my reference DAC(Beresford) which I consider to be quite neutral. Some trafos like the ones I got from a Ramsa mixing console sounded neutral right from the start others like the Jensens were close but needed a bit of tweaking to get it "right". On the other hand the bass of the A-20s or the thickness of the Cinemags was, IMHO, something that no amount of tweaking could alleviate.
What kind of capacitor would I want for this? All I can find in that size is mica - will that work ok?
Ok,I have been asked to upload a picture of where to cut the trace and where to solder the leads from the extra regulator (Salas or other).
If you look at the datasheet of LM317 http://www.national.com/ds/LM/LM117.pdf you see that the middle pin is the output,and that is the trace that is to be cut and the other regulator connected at the other end of the trace.
Here´s a picture of it:
The red dots are the middle pin of LM317,the 3 red lines is where you cut,(If you arent going to use extra regulator on the USB,don´t cut the last one at the end of pcb)(follow the trace from(the middle)the red dot so you´ll cut the right trace.
The small silver line just above the black cable is to mark the negative on the e-lyt that´s on the otherside of pcb,you can check this so it´s right.
If there´s any questions feel free to ask.
Åke
Ryssen
How much current you set for the shunt to work with the DAC?
I tried silver mica and then switched to polystyrene film & tin foil. The resistor on secondaries is a 13K carbon film Riken. On primaries I have foil resistors(510R) with copper-oil caps(0.001uf) I used copper-oil because that's what I had but something like Sprague 715p or 716p would be fine. I had originally tried 100R with 0.003uf on primaries but I found it a bit irritating. I may eventually try 220R with 0.0068uf that I have lying around but current setup sounds fantastic so I'm in no hurry.
I used Polypropylene Film capacitors and 1% Metal Film resistors on both the primary and secondary.
Ryssen is that the default value needed in the digital section (for both regulator on the DAC) ?
Hello Dears,
I had a strange problem with the dac. I take the digital output from the OPPO 980. I listened to music last night and when this morning I put on the system the OPPO started to read the disc but no output from the speakers. After the oppo had read around 1 minutes of music the dac started to sound.
That was very strange, isn't it? There is any explanation about that? Coudl it be a fault of the receiver or upsampler? Should I check something on the board? At the moment I am in the psychological position that I feel that there is something wrong with sound... but I am not sure whether it is because of this strange thing that happened. What should I check to make sure that everything is ok and no damage happened?
Best Wishes
Keph
I had a strange problem with the dac. I take the digital output from the OPPO 980. I listened to music last night and when this morning I put on the system the OPPO started to read the disc but no output from the speakers. After the oppo had read around 1 minutes of music the dac started to sound.
That was very strange, isn't it? There is any explanation about that? Coudl it be a fault of the receiver or upsampler? Should I check something on the board? At the moment I am in the psychological position that I feel that there is something wrong with sound... but I am not sure whether it is because of this strange thing that happened. What should I check to make sure that everything is ok and no damage happened?
Best Wishes
Keph
Hello Franz,
could it be a defective receiver? Even though it worked perfectly for a week.
yes the OPPO with its analag output. When I got this dac the improvement over the oppo analog output was impressive, now it seems that the difference is not that huge. But it could be a psychological issue.
If I think back to when it happened I believe I pushed the play button on the CD player before to power up the DAC. What does this cause?
Thanks for your help
Keph
could it be a defective receiver? Even though it worked perfectly for a week.
yes the OPPO with its analag output. When I got this dac the improvement over the oppo analog output was impressive, now it seems that the difference is not that huge. But it could be a psychological issue.
If I think back to when it happened I believe I pushed the play button on the CD player before to power up the DAC. What does this cause?
Thanks for your help
Keph
Hi all
I installed the STR's and there was no sound at all. I'm missing something obvious probably. These should work.
I removed the 317's and accomanying voltage setting resistors and connected the 317 inputs, outputs and ground to the respective STR point's. The STR's were tested and set to 5V and once installed and powered up I got good voltages around the DAC board and chips.
I replaced the 317's and resistors and the music is back.
I have posted on PFM for some STR advice but the DAC knowledge is on here so hopefully between you someone will know the answer
some pics:
Gigawork DAC :: IMG_1902.jpg picture by RichLund - Photobucket
Gigawork DAC :: IMG_1903.jpg picture by RichLund - Photobucket
Gigawork DAC :: IMG_1904.jpg picture by RichLund - Photobucket
Gigawork DAC :: IMG_1905.jpg picture by RichLund - Photobucket
I installed the STR's and there was no sound at all. I'm missing something obvious probably. These should work.
I removed the 317's and accomanying voltage setting resistors and connected the 317 inputs, outputs and ground to the respective STR point's. The STR's were tested and set to 5V and once installed and powered up I got good voltages around the DAC board and chips.
I replaced the 317's and resistors and the music is back.
I have posted on PFM for some STR advice but the DAC knowledge is on here so hopefully between you someone will know the answer
some pics:
Gigawork DAC :: IMG_1902.jpg picture by RichLund - Photobucket
Gigawork DAC :: IMG_1903.jpg picture by RichLund - Photobucket
Gigawork DAC :: IMG_1904.jpg picture by RichLund - Photobucket
Gigawork DAC :: IMG_1905.jpg picture by RichLund - Photobucket
Hi Ryssen
Thanks for the reply.
Yes the red LED's are lit. STR's are outputting 5.050V. Getting 5.05v at pin 22 of DAC chip.
There was an issue with the STR startup time (transistor wrong way round) which hopefully is sorted. How important is the speed of the DAC and reciever voltage supply on power up?
Other ideas:
- Should the voltage setting resistors (removed) for the 317's be linked out.
- Is there an issue with current, too little / too much.
These should work. It's only a simple 317 circuit they are replacing.
Thanks for the reply.
Yes the red LED's are lit. STR's are outputting 5.050V. Getting 5.05v at pin 22 of DAC chip.
There was an issue with the STR startup time (transistor wrong way round) which hopefully is sorted. How important is the speed of the DAC and reciever voltage supply on power up?
Other ideas:
- Should the voltage setting resistors (removed) for the 317's be linked out.
- Is there an issue with current, too little / too much.
These should work. It's only a simple 317 circuit they are replacing.