Yes, I said ES9039Q2M does not sound better. I did not say it sounds worse.
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The test software which generated the DoP signals was Multitone Analyzer ($0). For listening I use Daphile ($0) on a NUC ($50).
Other than that there is no need to continue this conversation unless you plan to build this RTZ dac.
And just for the record I did not say all dacs sound the same to me (https://www.diyaudio.com/community/threads/the-new-ess-es9039q2m.399437/post-7436248).
Other than that there is no need to continue this conversation unless you plan to build this RTZ dac.
And just for the record I did not say all dacs sound the same to me (https://www.diyaudio.com/community/threads/the-new-ess-es9039q2m.399437/post-7436248).
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Something else just occurred to me that is different between Marcel's dac and Andrea's. At the moment the Andrea DSD dacs here are of the 'Lite' series. They use one shared shunt regulated Vref supply for both channels.
OTOH Marcel's has two Vref supplies, one for each channel. There seems to be a bit of pseudo-stereo effect with Marcel's dac possibly because of differences between the two Vref supplies and or the way they are presently loaded. What I notice playing the song "The Voice" from Alan Parson's "I Robot" album is that sounds that are supposed sweep across the soundstage in the L/R direction are fading out a little as they pass through the middle area between the speakers. Its as though the phase of the two channels is a little bit off from each other. One way to find out if it is a power supply issue might be run both channels from a single Vref regulator?
OTOH Marcel's has two Vref supplies, one for each channel. There seems to be a bit of pseudo-stereo effect with Marcel's dac possibly because of differences between the two Vref supplies and or the way they are presently loaded. What I notice playing the song "The Voice" from Alan Parson's "I Robot" album is that sounds that are supposed sweep across the soundstage in the L/R direction are fading out a little as they pass through the middle area between the speakers. Its as though the phase of the two channels is a little bit off from each other. One way to find out if it is a power supply issue might be run both channels from a single Vref regulator?
This is a diy dac thread on a diy forum. Why should anybody interested in this dac care about what 95% of the population want. Or what you want to sell them.
Hi Mark,
Now you have two 4 bit shiftregisters with identical content in parallel for Vout+ and two identical content 4 bit shiftregisters in parallel for Vout-.
After the change you will have one 8 bit shiftregister for Vout+ and idem 8 bit for Vout-.
The first sinc zero will now be 2 times lower and because of that the HF content will be reduced significantly.
Hans
G
When feeding both channels with a mono signal at or close to 0dB, do the measure the same Vrms output ?
And what if you feed them with ca 30dB lower mono signal, are they still equal.
Now when feeding just one channel at or close to 0dB, is the other signal dead silent and vice versa ?
They are clocked with the same clock, so it can never be a phase difference.
Hans
Hi Mark,
When feeding both channels with a mono signal at or close to 0dB, do the measure the same Vrms output ?
And what if you feed them with ca 30dB lower mono signal, are they still equal.
Now when feeding just one channel at or close to 0dB, is the other signal dead silent and vice versa ?
They are clocked with the same clock, so it can never be a phase difference.
Hans
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True, to a first approximation anyway. However, the analog outputs are also multiplied by Vref. If Vref voltage dynamics chase the current load a little, then maybe something like phase intermodulation distortion? Particularly if it only happens with real music where one low-ish level sound is supposed to sweep across but other sounds are not supposed to move. In any case, seems like the first thing to do would be to try sharing a single Vref regulator and see what that does.
Okay. Plans have just changed. Hi end pro audio designer guy dropped by a took a listen. Been awhile since he listened to Marcel's dac. He says he doesn't like something about how it sounds now. Lost its 'ease,' he says. So will revert back in steps to see exactly where the 'ease' is getting lost.
Which is one of the reasons why there are two reference regulators in the first place, but the main reason is to be sure you can't get mixing products between the idle tones around fs/2 of the left and right channels.
Regarding the question whether two channels can work with one reference regulator, I think it should be possible for DSD256 and below. Remove either R16 or R141 and short the pad that is not connected to the emitter of a bipolar transistor to the corresponding pad of its colleague. Logically, it should either make things worse or not have much effect.
I think the question is what one believes in more: logic or listening. Both can be flawed: your listening tests, because they appear to be uncontrolled, so you could be fooling yourself like all participants but one in the pre-echo test I wrote about, and my logic because it is based on the models I have in my head, which could be too simple, and because neither of my parents came from the planet Vulcan
I don't think anyone claimed that they are on this thread. I certainly didn't.
True. However several people listening independently and who have been trained to use the same language to describe sounds should show some correlation in their descriptions if they are hearing something real. If they are imagining things then probably correlation between descriptions will be weak.
Turns out 'ease' appears to come back when Marcel's RTZ circuit is restored. Don't know if that's because both shift register phases with correct RTZ signals are cancelling out noise in the power supply, or for some other reason. Probably won't be able to test external RTZ with both inverting and non-inverting phases correct for maybe a few weeks. Might have another shipment from Italy in a couple of weeks and I could have the part I need included in that package. In the meantime don't see a reason why a trial of metal foil resistors would need to wait.