Hi,
desolder the SAA7220 from the board and cut off the pins 15, 16, 18 completely.
Solder an IC socket to the board instead.
There are kind of 24pin sockets that fit into IC sockets, and they are not for ICs but for resistors. So, resistor socket ?
Solder the chip onto that resistor socket and wire pin 1 to pin 18, pin 2 to pin 16 and pin 3 to pin 15.
Plug it into the socket on the board and you're done.
This allows for fast comparison of different sound os - non os.
Just did it to my CD880 and it works.
desolder the SAA7220 from the board and cut off the pins 15, 16, 18 completely.
Solder an IC socket to the board instead.
There are kind of 24pin sockets that fit into IC sockets, and they are not for ICs but for resistors. So, resistor socket ?
Solder the chip onto that resistor socket and wire pin 1 to pin 18, pin 2 to pin 16 and pin 3 to pin 15.
Plug it into the socket on the board and you're done.
This allows for fast comparison of different sound os - non os.
Just did it to my CD880 and it works.
Why not leave out SAA7220 ?? It kind of disturbs the 5V lines. Did you check how the 5V looks with and without SAA7220 ?
Connect the xtal to the 7210. If you are lucky the pcb is already prepared for that.
You can also dot that with an 7310 (smd) with 'close-combat' soldering techniques. If you look left at my avatar you can see what i mean (it is a bit blurred, but that's what it is).
mvg,
You can also dot that with an 7310 (smd) with 'close-combat' soldering techniques. If you look left at my avatar you can see what i mean (it is a bit blurred, but that's what it is).
mvg,
guido said:
Hehehe. "Close-combat soldering techniques." I like that.
A pity though as the government here has outlawed soldering irons with bayonet lugs. They consider them "assault irons." 🙂
se
Sa7220 is needed for digital out. You could try to just disconnect it from PS, but this affects I2S lines and the sound is much worse, when I2s lines are connected to not powered SAA7220 chip
Bernhard said:
The DAC needs a quality clock anyway so why not implement it ? Try it, you'll like it. As with all cdplayers the clock quality has great influence on end results.
Peter Daniel said:
I know that but some won't need the digital out. If one insists on going non os they are better off without SAA7220.
jean-paul said:
I need it to test my DACs😉 (and to copy CDs).
Marantz 94 has coupling transformer on coaxial output. As it supposedly not good, would it be better to use that output without any transformer at all?
Understood, that's why I use another cdplayer for copying 😉
The transformers are bad quality but I wouldn't want to give up galvanic isolation. I replace them for better types. Some report good results without the transformer but I guess they haven't compared the original one with a good one. In that case no transformer will be better than the original one 😉
The transformers are bad quality but I wouldn't want to give up galvanic isolation. I replace them for better types. Some report good results without the transformer but I guess they haven't compared the original one with a good one. In that case no transformer will be better than the original one 😉
jean-paul said:
Yes, and maybe S2.
I know it is difficult, but with the analyzer I can find combinations of chips that give a better result as a single chip.
could be that I built 100x160mm cards with 1 chip each.
So there is no such limitation in the number of paralleled chips 😀
That'll be a very expensive cdplayer. But you'll be tha masta in PCB design if you succeed 😉
Give it a go with paralleling as you desperately want to try it. I don't like the sonical results of paralleling despite the possible smaller distortion it'll give ( after a few years of matching 4 chips out of 100 ) 😀 You could consider making a new wafer for TDA1541A. Just joking, Bernhard.
First try a better clock if you haven't done so already. I am curious what a better clock will show on the analyzer.
Give it a go with paralleling as you desperately want to try it. I don't like the sonical results of paralleling despite the possible smaller distortion it'll give ( after a few years of matching 4 chips out of 100 ) 😀 You could consider making a new wafer for TDA1541A. Just joking, Bernhard.
First try a better clock if you haven't done so already. I am curious what a better clock will show on the analyzer.
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