SimontY said:Evening fellow modders,
I'm taking another look at my dead display. I swapped D851 for a new diode and replaced Q851 with a 7912. Neither of these changes made any difference.
The reg voltages are:
1- 0 (ground)
2- -37
3- -26
Just as it was before I changed the reg to a -12. I have no idea what's going on with it
Ok, measured more:
R854 measures -26v EACH side.
D853 reads 725mV in the diode test.
Simon
Remember when I tested this on my player and I removed the gnd pin so the output was -30ish. I still had display (just a little brighter).
The fact pin 1 is 0V then it must be ground.
Pin 2 for input is -37. This is too high. It sould be approx -31.5V
Why is the input so high. Measure across D851, the cathode should be -21V.
Also just to make sure go with what Andy said earlier and link between your gnd diode and go to star earth.
Brent
gy21 said:Is it a good idea to replace cd04/cd07 around dac with the elna silmic (dc blocking) ones that were removed earlier.
They have the same value.
I'm looking for some places to put the good silmic caps back somewhere
It certainly wont hurt. I put Black Gates in here and the sound was more detailed and less harsh.
Brent
adfinni said:
LOL !!!
I don't drink brent, what made you think that????
We went down to the pub for some grub and the footie, and it turned out to be an amazing game. middlesboro 1-0 down going into the second leg. With the score 2-1 to bucharest at half time, middlesboro came back to win 4-3
Had 3 pints of cider at the pub, then drunk another 8 cans of 6% scrumpy at home
Great night, and i hope you had a great birthday simon
Gooch, your right about that, top thread, and my sig does seem to get change all the time
I just thought of dead ants in boiling water, as a joke about lifespans of suicide bombers might offend people, and its summer the time of the flying ants.Brentty boy, your certainly right about the lifespan of my player, it likes to die, A LOT !
adam
adfinni said:
LOL !!!
I don't drink brent, what made you think that????
We went down to the pub for some grub and the footie, and it turned out to be an amazing game. middlesboro 1-0 down going into the second leg. With the score 2-1 to bucharest at half time, middlesboro came back to win 4-3
Had 3 pints of cider at the pub, then drunk another 8 cans of 6% scrumpy at home
Great night, and i hope you had a great birthday simon
Gooch, your right about that, top thread, and my sig does seem to get change all the time
Brentty boy, your certainly right about the lifespan of my player, it likes to die, A LOT !
adam
Can you write homoepitaxial?
I thought there was a new EC law !
List of CD-players vs. DACs
I've just started modding my CD-63mkII which I bought 2 weeks ago as second-hand. Infact I am finished with Phase 1, with the components I had available at home (bigger caps for additional decoupling of all the power lines, plenty of SMD X7R caps here and there in close vicinity of the ICs, rerouting the clock at the DAC etc). I am probably starting with the second final phase next weekend when I buy some additional components... By the way the CD-player started sounding a little bit deeper, the bass became stronger but more important razor sharp with a visible impact and high rising slope, while the subtle details I could only hear in much more high-end equipment has finally started to appear. Unfortunately, not in all tracks and it's maybe kind of placebo effect, but that's why I am going to continue with the modifications: separate PSU for the DAC, maybe an external clock and certainly a new analog filter. 2 weeks is definitely not a long time to get used to a specific sound of CD-player and notice changes in it after modifications.
I have the following question: Does anybody know of some list where substantial number of CD-players is listed together with the type (1-bit Sigma-Delta, multibit) and the chip number of the DAC implemented? That will probably help me and other guys around find a suitable CD-player for the next modification project. There are so many second-hand, old but good CD-players out there with bargain prices...
Thanks in advance,
P.
I've just started modding my CD-63mkII which I bought 2 weeks ago as second-hand. Infact I am finished with Phase 1, with the components I had available at home (bigger caps for additional decoupling of all the power lines, plenty of SMD X7R caps here and there in close vicinity of the ICs, rerouting the clock at the DAC etc). I am probably starting with the second final phase next weekend when I buy some additional components... By the way the CD-player started sounding a little bit deeper, the bass became stronger but more important razor sharp with a visible impact and high rising slope, while the subtle details I could only hear in much more high-end equipment has finally started to appear. Unfortunately, not in all tracks and it's maybe kind of placebo effect, but that's why I am going to continue with the modifications: separate PSU for the DAC, maybe an external clock and certainly a new analog filter. 2 weeks is definitely not a long time to get used to a specific sound of CD-player and notice changes in it after modifications.
I have the following question: Does anybody know of some list where substantial number of CD-players is listed together with the type (1-bit Sigma-Delta, multibit) and the chip number of the DAC implemented? That will probably help me and other guys around find a suitable CD-player for the next modification project. There are so many second-hand, old but good CD-players out there with bargain prices...
Thanks in advance,
P.
Re: List of CD-players vs. DACs
Hi,
http://www.freeweb.hu/mestertuning/dac.php?lang=hu
Warning there are a few errors in the document (such as saa7220 dac).
Google, and the forum is a good tool to confirm dac.
ratep2001 said:
Hi,
http://www.freeweb.hu/mestertuning/dac.php?lang=hu
Warning there are a few errors in the document (such as saa7220 dac).
Google, and the forum is a good tool to confirm dac.
transformer output
Having a pair of Lundahl 1646 1+1+1+1 : 2 + 2 audio transformers collecting dust, I wondered how they would perform with regard to the opamp or discrete outputs.
Not quite sure how to connect I would appreciate input on this matter.
Having a pair of Lundahl 1646 1+1+1+1 : 2 + 2 audio transformers collecting dust, I wondered how they would perform with regard to the opamp or discrete outputs.
Not quite sure how to connect I would appreciate input on this matter.
Re: transformer output
HI.
these are possibly not the best Txs to try - too many windings on the primary !
But if you want to try,
wire the primaries in series / parallel to give a centre tapped winding - centre tap to ground / hot ends to the DAC outputs
wire the secondaries in series - try straight to the amp via a 50k volume control [ the Tx must see a high impedance ]
Andy
disco said:
HI.
these are possibly not the best Txs to try - too many windings on the primary !
But if you want to try,
wire the primaries in series / parallel to give a centre tapped winding - centre tap to ground / hot ends to the DAC outputs
wire the secondaries in series - try straight to the amp via a 50k volume control [ the Tx must see a high impedance ]
Andy