PCM63 max compliance voltage

[regal]

Couldn't find the max compliance voltage for the PCM63 in the datasheet, I heard PCM1704 is 25mV, same for TDA1541.

Is 25 mV a good number to use for the PCM63 ?

 

[Bernhard]

IIRC it has a built in diode that causes clipping...

PCM56: 1000000 µV

 

[wildmonkeysects]

A while back Lynn Olson (if I may paraphrase) looked for spurs up out of the noise floor, and found 75 ohms or less to be ok.

My ears were/are happy with a 50 ohm "i/v" load feeding a Lundahl LL1674 amorphous core 1:8. Lowish output voltage, but very good sonics.

Share and Enjoy,

WMS

 

[Guido Tent]

A while back Lynn Olson (if I may paraphrase) looked for spurs up out of the noise floor, and found 75 ohms or less to be ok.

My ears were/are happy with a 50 ohm "i/v" load feeding a Lundahl LL1674 amorphous core 1:8. Lowish output voltage, but very good sonics.

Share and Enjoy,

WMS

Hi,

We have encountered long ago that 50 ohm might be some max value, consider the fact that the current output of the PCM DACs is not so good, and diodes start conducting a bit already at much lower voltages. Doede has done some measurements:

http://www.dddac.de/pcm63/DAC_I-V_Resistor.htm

We know use less than 1 ohm in our IV converter for the PCM1704

best

Guido

 

[regal]

Yes my experience with the PCM1704 showed excessive sibilance at more than 10 ohms.


I am designing a new tube DAC around the PCM63, if 50 ohms sounds as good as 5 ohms then I don't need to spend the $'s on expensive step-up transformers.

 

[Juergen Knoop]

consider the fact that the current output of the PCM DACs is not so good

I always thought that DACs don't have current outputs but switched resistors or caps and they need to be fed into a perfect (virtual?) ground in order to sum correctly.
Is there measured data confirming that simple resistors or transformers can do the job?
regards

 

[regal]

see the link Mr Tent posted above.

 

[Juergen Knoop]

aah sorry
is 0,05% distortion is a typical performance?
regards

 

[regal]

I am thinking its high, trying to discern the max compliance voltage to minimize this.

With the PCM1704 its a known 10ohms/25mV's. The sound definately improves when you get under 10 ohms.

 

[samoloko]

My ears were/are happy with a 50 ohm "i/v" load feeding a Lundahl LL1674 amorphous core 1:8. Lowish output voltage, but very good sonics.

Share and Enjoy,

WMS

would you please give detail about that setup