OneyedK said:
yes it works.. I will try and observe more carefully for when it does not go on. I remember I put in a CD it played then when I looked at the display it was blank. None of the buttons worked, except the power button to shut it off. When I turned it on again, it worked fine. I guess this happened two or three times.
My friends A73's problem is when the machine is turned on it does not work, he puts the disk in and gets "no disk" The machine needs to be on for a while to warm up and after that he has to keep pushng the play button many times. Like 4 or 5 mins and then the display goes on and the disk spins and plays.
I guess it's not just a display problem.
OneyedK said:
Well, for my friends, he will have to find someone and pay to fix it. That's too much for me.
As for mine, I will wait until I get at the other modifications you recommended to me, (It's been well behaved for the last 2 months in any case) and see what those changes produce.
Did you ever try a Phillips IS 5022 as a DAC or just to play around with ?
Changing caps is a rather simple soldering job in those machines, but it takes time and you have to select quality components.
I never played with IS 5022, but we TC finalizers and stuff like that at hands. Those are great mastering tools, but you really need to know what you are doing. I like old things like Apex studio dominator to shape sound.
But that's nothing you need at home. I only use it during recording and mixing.
At home I want honest playback of the original material.
I never played with IS 5022, but we TC finalizers and stuff like that at hands. Those are great mastering tools, but you really need to know what you are doing. I like old things like Apex studio dominator to shape sound.
But that's nothing you need at home. I only use it during recording and mixing.
At home I want honest playback of the original material.
mrtakib said:
That's the way it is done in most studio's, take a master clock, feed it in to the CD-player and feed it into the mixing desk.
If you want to buy a wordclock generator/distributor, those are pretty expensive.
(do not even look at the cheap ones, they really make things worse)
If you want to build one, you'll stiil have to start from a decent oscillator (like Tent or Kwak).
I think it's easier to build that oscillator directly into the player as decribed above.
OneyedK said:
I think you are right ! Guido from Tent is very helpful. I think I will go that route.
Some dac constructors advertise funny clock names that eliminate the jitter no matter what. I doubt that personally, but I can try out a Benchmark Dac1 and a Lavry DA10 for one week, as a loan from a dealer. I may do that next week just to hear them and also to try usb and toslink from my computer.
Still waiting for Twisted Pear to get the new PCB's....
About Oneyedk recommended changes
Oneyedk,
I read with a lot of interest this thread.
>>> About your suggestions:
- If you diminish the value of C411 from 100uf to 47uf, what will be the functional impact?
Better slew rate of the op amp IC403 just before?
Will it still block commutation noise as effectively?
- What is the role of the R416 you recommend to suppress and what is the functional impact?
- I do not understand why there is the muting mechanism Q401 & Q402, while there is an output mute through a relay (page 5/17) Q310/K301?
What is the purpose/functional impact of not having it? Avoiding pop-commutation noise?
- Based on those recommendation and the schematic (page 5/17 5/18), does it not make sense then to just remove both C411 & C301 and put a 47uf capacitor accross hence bypassing R416, R417, Q401, R419, Q402, C412?
- You mention replacing the op amps IC402, IC403, and IC405. How about IC301?(it is the last 5532 before the transistors).
- Based on your experience on the D73x, What components do you recommend to replace the op amp and capacitor (Brand/model)?
- Have you indeed tried to replace X701 by a Tentlab clock? What was the effect?
>>> I have an intermittent problem, where my D730 is suddenly starting to skip, the light "ext sync" starts blinking and the CD door is locked like it was "on air". Have you seen that problem before? The issue also happens without a CD (i.e., locking the CD door) so I assume it is not the drive.
>>> Finally since you seem to indicate that you have quite a bit of Studer equipment and some of it is end of life. If your company is getting rid of Studer CD players, Tuners or just boards (like the main boards of D73x or output board of A727, A764). Please contact me I am interested
Regards,
cdfr
Oneyedk,
I read with a lot of interest this thread.
>>> About your suggestions:
- If you diminish the value of C411 from 100uf to 47uf, what will be the functional impact?
Better slew rate of the op amp IC403 just before?
Will it still block commutation noise as effectively?
- What is the role of the R416 you recommend to suppress and what is the functional impact?
- I do not understand why there is the muting mechanism Q401 & Q402, while there is an output mute through a relay (page 5/17) Q310/K301?
What is the purpose/functional impact of not having it? Avoiding pop-commutation noise?
- Based on those recommendation and the schematic (page 5/17 5/18), does it not make sense then to just remove both C411 & C301 and put a 47uf capacitor accross hence bypassing R416, R417, Q401, R419, Q402, C412?
- You mention replacing the op amps IC402, IC403, and IC405. How about IC301?(it is the last 5532 before the transistors).
- Based on your experience on the D73x, What components do you recommend to replace the op amp and capacitor (Brand/model)?
- Have you indeed tried to replace X701 by a Tentlab clock? What was the effect?
>>> I have an intermittent problem, where my D730 is suddenly starting to skip, the light "ext sync" starts blinking and the CD door is locked like it was "on air". Have you seen that problem before? The issue also happens without a CD (i.e., locking the CD door) so I assume it is not the drive.
>>> Finally since you seem to indicate that you have quite a bit of Studer equipment and some of it is end of life. If your company is getting rid of Studer CD players, Tuners or just boards (like the main boards of D73x or output board of A727, A764). Please contact me I am interested
Regards,
cdfr
I had same problem on my A730, it needed some time to warm up before he wanted to play.
I located problematic component by cooling-warming method, and it was little BF450 transistor in current ref. circuit for SAA7210 decoder. It is located near SAA7210 chip.
I have a similar problem on a modified A 730 with a D 730 transport ( CDM 4 instead of CDM3).
Sometimes the player refuses to play. Turning off the machine for a while and pushing the play button several times as mentionned by mrtakib helps.
I will check the BF 450 transitor you mention but don't you think it may be the laser head which needs to be replaced as well since this is a quite old machine ? Or maybe the machine needs to be tuned up. For this Test CDs are required and and a repairer who accepts to do the job !
I tried to use an external DAC ( Benshmark dac 2) but it is worse. Maybe a jitter problem mentionned above.
Also I was wondering if switching the clock inside to "Quarz Clock" would be better ? the other position is for varispeed and wordclock input.
Thank you for any advise.
Sometimes the player refuses to play. Turning off the machine for a while and pushing the play button several times as mentionned by mrtakib helps.
I will check the BF 450 transitor you mention but don't you think it may be the laser head which needs to be replaced as well since this is a quite old machine ? Or maybe the machine needs to be tuned up. For this Test CDs are required and and a repairer who accepts to do the job !
I tried to use an external DAC ( Benshmark dac 2) but it is worse. Maybe a jitter problem mentionned above.
Also I was wondering if switching the clock inside to "Quarz Clock" would be better ? the other position is for varispeed and wordclock input.
Thank you for any advise.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.