That's funny.
So again, what would the coupling mechanism be for USB noise to turn into ground noise in the vicinity of Vref?
You can see results of the coupling mechanisms in e.g. the Intona link I posted earlier. Now do you have any proof that those cannot impact Vref?
why should I consider the rest of the chain when I can hear what the DAC is doing and what my system is doing?
my system is good. Pretty darn linear.
as I said. I have a benchmark LA4 pre and AHB2.
measurements in room are pretty darn good and flat. Especially after the treatment I put in.
i get what you are saying. But I didn’t like those DACs.
i have played music for over 35 years and know what instruments sound like.
which DAC of those which I mentioned do you like if you don’t mind me asking.
and pardon I’m not trying to be snarky.
Where is the coupling happening in that Intona link? Its an unbalanced connection so I have an idea but I'm curious to learn of your analysis.
Of course if you have ground plane currents running under your Vref, they can impact Vref as registered at the DAC chip, that's not rocket science. So are you admitting the presence of ground plane currents originating from your USB source in your DAC designs? If so, then you can fix that with better PCB layout. Read some Henry Ott perhaps.
You seem to be too agitated to notice that this discussion was about Topping D30 Pro, not about general DAC design. No need to resort to ad hominem attacks.
Neither do I. Non of them. But I do listen to smsl su-6 at the moment and in an EQed system, it sounds very nice.
No EQ, no win ;-)
Whats the rest of your system if I may ask? Do you really need a pre-amp?
//
It is truly funny that when you were given a plausible explanation you turned to ad hominem attacks which just proves you lost the argument.
Fellas ,
any other info on whether it’s worth modding that DAC?
instead of arguing amongst each other ?
please don’t argue in my thread
any other info on whether it’s worth modding that DAC?
instead of arguing amongst each other ?
please don’t argue in my thread
You can try to "piggyback" some SMD capacitors.
If you have some 100nF 5Volt 0603 capacitors, you can add a 3,3uF cap on top for extra decopling.
Quite risk free and will do some improvement especially on the analog ref voltage on the DAC chip.
You can also take aluminum tape and cut pieces that has same size as the dac chip and op amps. and stick them on top, if you make the longer than the chip you can fold the edges 90 deg so that you crate cooling fins. You form a virtual "ground" plane" at the same time as you decrease thermal resistance.
If you have some 100nF 5Volt 0603 capacitors, you can add a 3,3uF cap on top for extra decopling.
Quite risk free and will do some improvement especially on the analog ref voltage on the DAC chip.
You can also take aluminum tape and cut pieces that has same size as the dac chip and op amps. and stick them on top, if you make the longer than the chip you can fold the edges 90 deg so that you crate cooling fins. You form a virtual "ground" plane" at the same time as you decrease thermal resistance.
Well you have an opamp for R+, R-, L+, L- followed by what looks like a differential buffer. Perhaps matching the opamps to tighter specs may help but my first target would be the power supply for them and ensuring each has a good enough power supply (and clean). Also the same for the DAC chip too.
Do you have a close up of the clock oscillator? And more importantly the power supply for that too (adds noise to the clock and so phase noise ie jitter).
In the end without measuring the noise before and after it will all be guesswork.
If the power supplies turn out to be noisy then it'll be a waste of time and effort to swap out those opamps. Even with quiet power, to do better you'd likely need a discrete solution which wouldn't be for the faint-hearted.
If you dream about huge improvements you can chack out this:
https://www.audiosciencereview.com/forum/index.php?threads/topping-d30pro-review-balanced-dac.20259/
2nd harmnic distortion is on -135dB so how high volume do you think you have to play in your room until this signal will be measureble or even audible?
If we had this DAC to improve upon there could be some dB to gain, but D30...?
https://www.audiosciencereview.com/...urements-of-furutech-adl-gt40-dac-phono.9279/
https://www.audiosciencereview.com/forum/index.php?threads/topping-d30pro-review-balanced-dac.20259/
2nd harmnic distortion is on -135dB so how high volume do you think you have to play in your room until this signal will be measureble or even audible?
If we had this DAC to improve upon there could be some dB to gain, but D30...?
https://www.audiosciencereview.com/...urements-of-furutech-adl-gt40-dac-phono.9279/
the measurements don’t solve the problem the D30 pro has sound wise
i stand by that 1000%
Just leave it like it is. No knowledge means expected failure. Makes no sense.
You can actually try another thing. If there is ceramic caps in the signal path you can add sticky "blue tac" or use thermo glue on them. This will reduce vibrations and microphonic feedback.
Maybe some of you think that this is woodoo? You can easily test this by solder a cheramic cap to an RCA cable and plug it in on the phono preamp input.
A simple short cut... then you tap on it and listen.
You will be surprised to hear all that noise!
So this is basicly why people tend to put their hifi gear on solid or suspended shelfs.
Maybe some of you think that this is woodoo? You can easily test this by solder a cheramic cap to an RCA cable and plug it in on the phono preamp input.
A simple short cut... then you tap on it and listen.
You will be surprised to hear all that noise!
So this is basicly why people tend to put their hifi gear on solid or suspended shelfs.