I don't have the TL072 model you do, the message only said the symbol was missing not the whole model. Sorry.
The problem is still that that the source as you have defined it has a DC offset between its two terminals, not an offset with respect to ground. The opamp may not work with a floating source with a 2.5v DC difference between the the opamp inverting and noninverting inputs, which is roughly what you told the source to do.
The problem is still that that the source as you have defined it has a DC offset between its two terminals, not an offset with respect to ground. The opamp may not work with a floating source with a 2.5v DC difference between the the opamp inverting and noninverting inputs, which is roughly what you told the source to do.
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Yes. Inside the dac chip the outputs are in fact referenced to ground, not floating differential.
What is the current consensus for the best CS4398 output filter? I am considering post 2 and post 4 as two possibilities:
CS4398 output filter
CS4398 output filter
Any others that I should consider? I have OPA1612, OPA2134 & LM4562 available.
CS4398 output filter
CS4398 output filter
Any others that I should consider? I have OPA1612, OPA2134 & LM4562 available.
The one without electrolytics in the audio path probably sounds cleaner in most ways, but the one with electrolytics might be a little more low noise (possibly not counting any signal correlated noise; some electrolytics might be one source of it, not sure).
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I used this version in my WM8804/CS4398 DAC and sounds great. For opamp I used OPA827. 2.2uF seems to work fine, but depends on the input impedance of your next stage.
Didn't yet test the muting circuit, I didn't populate it.
Didn't yet test the muting circuit, I didn't populate it.
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That is an interesting idea for the OPA1632 making use of the common mode input. Have you tried it? I have a couple OPA1632 modules (not bare die) on the way for a different usage.
Using ferrite beads on audio opamp power rails may have untoward effects on sound. Suggest trying it with and without those. See what you think.
What did you use for the power supplies?
On my PCM1794 board I used the LM317 & BC337-40 denoiser. (One for the digital supply and one for the analog supply.) The IV stage is powered by LM317/LM337/LF353 low noise supply.
I am pleasantly pleased with how my board is sounding and this is with just the PCM1798 installed for the first test.
Noise modulation does not show up on most test instruments. FFT can show it if one knows what to look for.
Unsubstantiated claim, aka FUD.
The ubiquitous noise modulation is back. Set aside noise modulation shows (if it exists) pretty well on a FFT, as a reduction of the dynamic range, nothing more or less, Maxssau is correct, a VNA will show the difference with/without any ferrite beads.
Okay. Still believed to be good advice for audio: Listen to your diy project with one change at a time, and decide for yourself what you think.
Have you been replaced by a bot that posts about noise modulation every 5 days in response to posts where it is not at all relevant?
I used LM3x7N (SOT223) + dienoiser with BC8x7 for everything. Two 3.3V ones for digital (WM8804/CS4398), one for 5VACC, one for 3.3VAPLL, and two +-12V for opamps. CLC for digital and CRC for analog.
Might be overkill, but everything fits on a dual layer 83x86mm board. It was a straight swap for the older AK4396 pcb that I had. One of those ebay kits.
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In a general sense to me hysteresis distortion is a subtype of noise modulation:
This Thing We Have About Hysteresis Distortion - PURIFI.
For some purposes it may properly viewed as a reduction of DNR. Nonetheless, according to Bruno there can be objectionable audible artifacts associated with it.