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I have a YBA Lecteur CD player that sounds amazing. I've never heard a 'modern' CD player or outboard DAC so I don't know if the DAC in my CD player sounds so good because it's the only one I have, or because it really does sound good. Anyhow, it does not have a digital input. I'm wondering if it's a big project to add a digital input to this thing so that I can use it as both a CD player and an outboard DAC ????
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In the absence of a service manual it'll be a very daunting project.
Since CD players are by design clock masters I reckon your best bet at getting a solution is to implement an async USB interface - that way the player still gets to be clock master. Any other interface (S/PDIF for example) it has to be a slave and that's fraught with extra challenges.
Since CD players are by design clock masters I reckon your best bet at getting a solution is to implement an async USB interface - that way the player still gets to be clock master. Any other interface (S/PDIF for example) it has to be a slave and that's fraught with extra challenges.
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Hi and sorry to jump in but i have the same curiosity
So if a service manual is available it can be done ?
I am on the same track of the thread Starter. Many exceptional old cd player can be found around but of course very few with digital inputs.
Often the mechanic goes bad and what remains is just an unusable box ... What a waste of electronics ...
Thanks and regards, gino
the original poster's question comes up occasionally.
i must admit to thinking about it sometimes myself.
does anybody have any links to a project where some diyer actually has successfully completed such a modification to his/her machine?
i can imagine one immediate, big problem would be getting data for old interface chips in the cdp ...
mlloyd1
i must admit to thinking about it sometimes myself.
does anybody have any links to a project where some diyer actually has successfully completed such a modification to his/her machine?
i can imagine one immediate, big problem would be getting data for old interface chips in the cdp ...
mlloyd1
Hi i do not know if you are referring to me ?
In case my point is that it could be possible to find an old but very good indeed cd player with a dead and not serviceable drive for instance for lack of spare parts, and so the digital section goes wasted.
Lately as a digital source i am more on pc based systems for their flexibility even if to set up a pc based system good sounding is a challenge.
But for instance i have also this thing here that to my ears sound very very good indeed i could easily recommend to try to anyone
it has a rca spdif out of quite good quality, while the internal dac and output stage are not that exceptional.
I have listened to it in a very high level system and it sounded very good.
I know that this seems strange but ... digital is a really strange beast.
Another case that has puzzled me a lot indeed.
I had the opportunity to listen to a very old cd player ... a Grundig cd7500
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i heard an extremely musical sound that with digital is a real surprise
I did not buy it (my mistake) because it did not have a remote and because i was worried about the reliability of the transport.
But if i knew how to transform it as a dac i would have bought it immediately because i loved its sound ... was like analog.
I think that with analog the background noise and the musical signal are more separated ... i cannot explain better
And the sound flows more effortlessly ... relaxed and in the end pleasant.
Thanks a lot again.
Gino
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I don't know why you'd want to keep the master clock of the cdp if you transform it into a DAC. Just use the recovered system clock from the spdif or usb receiver you'll have to use.
It's trivial to mod an older cdp if you can trace the inputs to the digital filter (of which datasheets can usually be easily found). Then it's just a matter of following the tracks until where they can be cut/disconnected and new inputs injected.
The real problem with older cdp is that they might not use the current standard I2S but older protocols. This will often be revealed by the datasheet of the digital filter (or of the dac chipset if it's integrated) and a compatible receiver will have to be found. Another problem is more analog: the cdp might have muting or sleep features you need to bypass. This can be quite difficult in practice.
It's trivial to mod an older cdp if you can trace the inputs to the digital filter (of which datasheets can usually be easily found). Then it's just a matter of following the tracks until where they can be cut/disconnected and new inputs injected.
The real problem with older cdp is that they might not use the current standard I2S but older protocols. This will often be revealed by the datasheet of the digital filter (or of the dac chipset if it's integrated) and a compatible receiver will have to be found. Another problem is more analog: the cdp might have muting or sleep features you need to bypass. This can be quite difficult in practice.
Btw, the grundig cd7500 is a perfect clone of the philips cd303. The service manual can easily be found with google.
It uses a saa7030 DF with two tda1540 DAC. This will not be easy to interface with any modern inputs for digital formats reasons. Some pointers in this thread: http://www.diyaudio.com/forums/digital-source/42788-how-connect-cs8412-os-filter-2.html
It uses a saa7030 DF with two tda1540 DAC. This will not be easy to interface with any modern inputs for digital formats reasons. Some pointers in this thread: http://www.diyaudio.com/forums/digital-source/42788-how-connect-cs8412-os-filter-2.html
Hi and thanks for the very interesting advice.
Just one question a little OT.
I see that the tda1540 is only 14 bits
and still once i heard very nice sound from this cd7500. Am i hearing things ?How can it be possible that a "14 bits only" unit sounds so good and above all that musical ? i listened to a piano recording and was excellent ... the instrument had a real body a very nice tone.
What do you think ? Thanks a lot again, gino
DAC subjective sound quality isn't a function of the number of bits - the TDA1540 was using a degree of noise shaping (in the digital filter) to improve the resolution. to closer to 16bits. Even without that noise shaping the tonality would beat out an S-D DAC - which nowadays are 6bits run very fast (high OS ratio).
My point of view (the one most commonly held in the industry btw) is that those old dac, using really awful digital filters, are distorting the sound and thus are less accurate than modern sigma delta DAC.
Some might prefer what they add to the sound though, sound "quality" being highly subjective.
PS: if I was searching a CDP to mod as a DAC, I'd have a look at the Arcam CDP using the wm8740 for example.
Some might prefer what they add to the sound though, sound "quality" being highly subjective.
PS: if I was searching a CDP to mod as a DAC, I'd have a look at the Arcam CDP using the wm8740 for example.
Hi and thanks and yes is the tonality that impressed me mostly.
The piano was really real ... with a lot of body. Very beautiful.
It is not the first time that measurements and sound do not come together.
But nowadays i am addicted to pc or streamers as digital sources.
So i am more interested in dacs than complete cd/dvd players.
Thanks again, gino
Hi and thanks a lot for the very valuable advice.
What about instead the Wolfson 8742 ? is it in the same league of the 8740 ?
In the meantime i have discovered that my Cambridge Audio Dacmagic 100 is based on the Wolfson 8742
Thanks again, gino
I take it it sounded like the piano was real rather than a facsimile. Its a characteristic of multibit DACs that they sound more lifelike, in general. But they don't do this at the expense of measurements (well perhaps TDA1543 does) - TDA1541A for example delivers about the most impressive set of measurements of any 16bit DAC.
I doubt it'll be the last either.
There are some measurements which reveal the deficiences of S-D DACs (noise modulation). But they do have to be chosen carefully according to the architecture of each.