4490/93/97 - are Voltage Output, 99 - Current.
P.S. Paralleling doesn't make sense for all of them, but that's up to you...
Alex.
I have experience with paralleling AK4499EX. I did version in dual mono and last weeks I did stereo verison. There is a really small difference. As you said, there is no sence to do this. In my case I would like to achieve total dual mono system. Dual mono DAC, two monoblock amplifiers.
What do you mean you have clipping on the pins? Are you sending a valid test signal with no intersample-overs? Do you see clipping before any I/V stage or after some output stage? Do you still have clipping if you don't tie the pins together? Right now, its not completely clear what you are doing.
I agree with paralleling dacs... especially with tube output where distorsion goes signifficant high.
Maybe you misunderstund me ...i do not develop anything, I just want to solve the design that was done with failure and sold in many numbers, Because it is not so hard promoted or advertised, it was never measured at any review. And AK4499 module was not so often as ak4490 or ak4497. Probably nobody was heard that clipping because it is not present with -9db lower signal, And on tube output it is smooth.
When i compared it with Rega Isis valve cd player, i immediately heard that something is not ok, therefore i put it on a surgery table.
NEW FINDING. When dac goes from HI-Z (mute) to IDLING just half of a dac outupt i active. so only on EXTCX1X pins is 2,5vDC on other side EXTCX2X almost zero ...40mv. I think some protection is activated. It is hard do disconent pins and if i unsolder and bend them out it can be easily broken and is no way back.
Any confirmation or how to go on with less posible damages?
Thank you
Maybe you misunderstund me ...i do not develop anything, I just want to solve the design that was done with failure and sold in many numbers, Because it is not so hard promoted or advertised, it was never measured at any review. And AK4499 module was not so often as ak4490 or ak4497. Probably nobody was heard that clipping because it is not present with -9db lower signal, And on tube output it is smooth.
When i compared it with Rega Isis valve cd player, i immediately heard that something is not ok, therefore i put it on a surgery table.
NEW FINDING. When dac goes from HI-Z (mute) to IDLING just half of a dac outupt i active. so only on EXTCX1X pins is 2,5vDC on other side EXTCX2X almost zero ...40mv. I think some protection is activated. It is hard do disconent pins and if i unsolder and bend them out it can be easily broken and is no way back.
Any confirmation or how to go on with less posible damages?
Thank you
Mark clipping is present on all Iout pins and also after tube stage ...there is bit smother and not so hearable.. So on all Iout pins is voltage signal before tube stage. Division ... 2,1V in negative and because of cliping around 1,7v in posistive periode.
At output signal is inverted because of SRPP stage... and very loud because of e88cc tubes inside...
At output signal is inverted because of SRPP stage... and very loud because of e88cc tubes inside...
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Are you overdriving the tubes, or it it the dac chip? I mean a tube can be driven into grid conduction, or driven into cutoff.
It is dac , with ak4497 signal is maybe tiny larger and no clippung before an after tube stage.
What voltage is VDDL/R, and VSSL/R? What is VCOM? IOW, what are the bias voltages for each dac output channel?
5 and VCOM-2.5V and around 2,5V on all Iout pins. Half of dac is in High Z state because there are no voltages on EXTCR-L 2 just on EXTCR-L 1 outputs.