Old TDA1540 as a "modern DAC"

Looks like its making the dac into a simple version of a modern sigma-delta noise shaping architecture.
That is exactly the magic Philips did: the digital filter produces a 14 bit sigma-delta modulated signal moving quantization noise out of the audio band and increasing the resolution to 16 bits. It's the same principle, taken to the extreme, used later in the 90's with the 1 bit DAC.

But in the 80's, when other other players used very rudimentary DAC (e.g. constant current source charging a cap for a time proportional to the 16 bit word value), the trick used for the TDA1540 was pretty advanced.
 
How far have you got with this?
Did you read the links I supplied in my earlier post?

What you want can be done...............
SPDIF into one of these (for example)............

( https://www.ebay.co.uk/itm/14261724...TZf5I7UIsdqYra+1N+CtZ23ka50B|tkp:BFBMzOSGp_9h )

Then the i2S out of that into one of these (from a nice fellow who posts on this Forum sometimes)...........

( https://www.ebay.co.uk/itm/32523126...awu++H2i84n/Nnw87ngmbbkg==|tkp:Bk9SR_KKkaf_YQ )

Then the Output from that board into the DAC part of your CD Player, straight into the TDA1540's. This will give you NOS and no Digital Filtering which is not to everyone's taste but actually the 1540 works quite well without any of that, IMO.

A bit of bedtime reading and you should be able to work out how to connect it all up.

Good luck.

P.

P.S. What Philips Player with TDA1540's has stopped reading Discs. Are you sure this can't be resurrected?
 
I would like to share this video you all you:


It's in spanish... but what he is basically saying is that people are wrong about the sound of the TDA1540. He says that it doesn't matter what CD player you're listening to: they all sound the same and any difference you notice is mere suggestion.
In the video he is performing a blind test between a player with TDA1540 and a modern player with a different architecture. He says that neither he nor other people who have agreed to do the blind test have been able to notice any difference.

It's hard for me to believe this, because I have several players with different variants of the TDA1541, in addition to a player with 1540 and also a Philips CDF200 player that has a totally different architecture than the previous ones. I can notice certain differences between all of them. I have told this to the author of the video through the YouTube comments, and he has answered me that those small differences that I notice are due to suggestion.
What do you think about this? Do you think it's suggestion? or are there real differences?
 
It depends. What is his whole reproduction system like? Is if full of class D amps, ground loops, radio shack speakers, etc.?

Could be there are enough problems with the system to mask real differences between players.

One way to know more about the system would be to listen to it with a high quality analog reference, such as high quality phono or tape, and with music you are very familiar with.

Of course, listening to a youtube video doesn't tell you much. The audio is lossy encoded to begin with.

EDIT: Just listened to a few snippets of the video, IT SOUNDS HORRIBLE! Really bad. Suggest to ignore it totally.
 
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