Question : marantz cd6000 mod with NOS TDA1541

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hi there,
I am thinking of modifying my cd6000 OSE by replacing the 2 on board DAC sm5872bs with TDA1541A don't know if it is feasible.
From the schematics, the I2S data generated from SAA73720( which does not do any oversamling.) Then passed to this "strange" IC TC160G11AU which split the I2S data in to DOL/DOR and feed into 2 SM5872BS (L/R).
I am thinking of just replacing the SM5872BS with TDA1541A and still using the on-board HDAM stage to do filtering.
But there are some questions on the strange IC which did the data spliting which I hope some one can help.
I cannot find any spec of the IC so do not know if the IC did any signal processing before sending the split I2S data to the DAC. Also cannot confirm if the split data still be able to decode by other DAC.
Does anyone have any clue on the function of the IC apart from spliting the I2S data ?
Has anyone tried this before ?
 
hi,

managed to get 1 channel working !! However need fine tunning on the level. The original differential HDAM in CD6000 not suitable for TDA1541A.
so now 1 channel of the set is driven by a TDA1541A configured in differential mode and using the on-board HDAM stage with some cap's and resistor value changed.

Question :

1) in the spec of TDA1541A, the filter resistor/cap value are 1.8K and 2.2nF cap. in most philips set it is 1.5K with 2.4nF cap. In this case since i am driving it in differential mode, can I just half the resistor value (to get the correct output level)? or the 1.~K ohm value is a magical value ?

2) calculating the suggested value in the spec of TDA1541A, the -3dB cutoff freq is ~40K, any additional filter stage required ?
 
the set is up and running !!! :)

output from DAC TDA1541A only feed to the inverting path of the original differential HDAM filter.
the feedback resistance of first HDAM stage is changed from 12K to 820 ohm and feedback cap change from 120P to 470P.

Level now at 1KHz odB ~ 2.3Vrms.
However the low and high seem to drop abit ~1-1.5dB (at low 20Hz, and high >~ 10KHz).

try to replace first HDAM stage with NE5532 and LM6172..... results not so impressive.... in fact sound abit odd !! (dun noe y????) :confused:

with original HDAM stage the sound is more natural (Compared to CD850 and the new philips DVP9000)

Tent clock is also added !!
Although there are still a few things not tuned, the set is my "reference" source for CD now !!:D
 
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