I would suspect that the clipping is occurring on the digital side of the DAC chip.
It certainly is looking that way from your measurements.
If there is not enough bandwidth in the digital receiver then clipping would occur.
If there's not enough bandwidth in the digital receiver then either no signal will be received, or the received signal will be corrupted. In neither case will the result be clipping of the reconstituted analog signal.
I will take the Dido CD out to the shop and look at the output across the 50 ohm i/v resistors.
OK, your measurements make sense - the DAC output current max is 4mA, you see 200mV into 50ohms. The supply to the DAC is +/-5V, but that's not a limitation on the signal. When you say 'the peaks disappear' then do you mean you see flat-topped signals (where the tops are +/- 100mV) on your scope?
To answer your final question - if the output signal is being limited by the TDA1541A's output compliance, then active I/V might solve the problem. But the fact that you are getting 200mV p-p signal (as predicted by theory) makes me think this is not the issue - so I'll venture that active I/V will make no difference.
Since the DAC has a current limit of 4 mv, if the clipping is not in the digital section, shouldn't we be able to raise the voltage and avoid clipping with a properly constructed active i/v?
I have apprised Mr. Zou of the problem. I am sure he is looking into it now and will get back to me soon.
I know its a couple of years now since Raindrop Hui's DAC DIR9001+TDA1541 2.0B parallel output OS/NOS | eBay was hot off the market, but I've got one and am about to case it up.
Can anyone point me to any 'mods' necessary for this unit.
Cheers chaps!
Can anyone point me to any 'mods' necessary for this unit.
Cheers chaps!
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