It's leaving a strong first impression Marcel.
After a while I will play around with some different reconstruction filters, probably a separate low voltage supply for the clock and maybe even a LCLC power supply for -300V. Not sure if any of those things will make a difference.
There is a choke loaded power supply here about to be wired up to go into a preamp. It will suit the ValveDac so perhaps it could be trialled there first.
After a while I will play around with some different reconstruction filters, probably a separate low voltage supply for the clock and maybe even a LCLC power supply for -300V. Not sure if any of those things will make a difference.
There is a choke loaded power supply here about to be wired up to go into a preamp. It will suit the ValveDac so perhaps it could be trialled there first.
I can highly recommend the 5000 serie with built in function generator and loaded with all kind of analog and digital features.
Ultra reliable, also for the 200Mhz probes.
https://www.picotech.com/download/datasheets/PicoScope5000Series.pdf
There are also PicoScope versions with less features but all very good.
With FRA4PS you can make very reliable bode plots and even turn your picoscope into a VNA.
Hans
Glad that you got yours working, acg! There are so many little things that can go wrong. Your 85a2 tube is crazy bright compared to mine! I wonder if it's because mine is smoked glass?
The thickness of the molybdenum getter layer that is sputtered on the inside of the glass also differs a lot from one brand to the next. I once bought four 85A2's, each from a different brand, and the Pope 85A2 had such a thin getter layer that you could see the electrode structure shine through far more clearly than with any of the others.
You have the DAC up and running via the I2S input. Do you still want to debug the S/PDIF inputs?
Amazing
Hi this is an amazing approach that you updated the 1rst Message! So a newcomer like me immediately can see the most important parts in the thread. Really thanks for that! Szabolcs
Hi this is an amazing approach that you updated the 1rst Message! So a newcomer like me immediately can see the most important parts in the thread. Really thanks for that! Szabolcs
That's thanks to Ray, a.k.a. nautibuoy. I didn't even know I could edit the first post until he pointed it out. It also helps me to find things back.
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We've had two PCB group buys, one for the original version and one for the DSD-only version.
As far as I'm aware acg and SonnyMarrow have their original versions up and running and I have my DSD-only version.
Where are all the others?
This project deserves to be build and really rewards the effort with some amazing sounds.
I have to mention Marcel too - the support he provides to builders of his design is simply amazing and should be seen as a confidence booster to potential builders who might be considering taking on this project.
As far as I'm aware acg and SonnyMarrow have their original versions up and running and I have my DSD-only version.
Where are all the others?
This project deserves to be build and really rewards the effort with some amazing sounds.
I have to mention Marcel too - the support he provides to builders of his design is simply amazing and should be seen as a confidence booster to potential builders who might be considering taking on this project.
Yes, input is solely I2S at this stage and I would like to get the spdif operating. I've not tried it since everything has been working so it may well just work. Am travelling now so will get back to it next week sometime.
My understanding is that i2s is automatically selected by the dac if the signal is viable which means somehow disabling the i2s to make the other inputs available. Is this right?
ValveDac sounds very good Marcel. Was listening this morning before leaving and was enthralled.
My understanding is that i2s is automatically selected by the dac if the signal is viable which means somehow disabling the i2s to make the other inputs available. Is this right?
ValveDac sounds very good Marcel. Was listening this morning before leaving and was enthralled.
When P9 pin 1 is low, the DAC selects the I2S input and when it is high, the DAC selects the signal from the DIX4192 S/PDIF interface chip. An internal pull-up pulls P9 pin 1 high when you don't connect it. I'm glad you like the sound!
Ray
As far as I know you also have the DSC2? Is it the latest with onboard X-tal osc.? And how would you rate the valve DAC to the DSC2? To my ears the DSC2 is a very good DAC nothing has surpassed it here, but I have some issues, as there is no such thing as an USB to DSD with more than 2 channels. I need at least 3 ;-(
A number of the No-dacs I experimented with sounded as good, but had(very low level and occasionally noise issues)
So currently I am using a Khadas tone Board that is the closest I can find to the No-DAC performance.
Both DSC2 (v2.5.2) and Valve DAC are astonishingly good decoders and better than any chip-based DAC that I have heard (though there are lots I've not heard) - that's using them with HQ Player.
Both use a Beaglebone as HQP NAA (with Pavel's 'Pure' software loaded). The DSC2 has a Twisted Pear Hermes/Cronus reclocker and the Valve DAC has Pavel's reclocker.
To me the Valve DAC just wins out for sound quality, it is richer and more organic sounding, but the DSC2 wins for convenience, there is no adjustment/tweaking required. I can happily listen to either of them though.
Both use a Beaglebone as HQP NAA (with Pavel's 'Pure' software loaded). The DSC2 has a Twisted Pear Hermes/Cronus reclocker and the Valve DAC has Pavel's reclocker.
To me the Valve DAC just wins out for sound quality, it is richer and more organic sounding, but the DSC2 wins for convenience, there is no adjustment/tweaking required. I can happily listen to either of them though.
Marcel, you did a fantastic job designing this Valve Dac, even equipped with several different filters and 3 Delta Sigma settings.
What is the opinion of the users so far, what they favour for all these various options ?
Hans
What is the opinion of the users so far, what they favour for all these various options ?
Hans
It's only the original version of Marcel's decoder that has those options and, as per my earlier post, there seem to be only two of those that have been built (other than Marcel's) and then only recently so I doubt there's much informaton to report.
I achieve the modulation for the DSD-only version with HQ Player, which has many options. FWIW I've settled on DSD256 with poly-sinc-ext2 as the filter and AMSDM7 512+fs for the shaper.
I achieve the modulation for the DSD-only version with HQ Player, which has many options. FWIW I've settled on DSD256 with poly-sinc-ext2 as the filter and AMSDM7 512+fs for the shaper.
Hans, just seven albums into my ValveDac and could not even tell you which filter or sdm method it is set to, let alone which I prefer as I've not moved a single switch since getting it working. Preferences will come in time.
I haven't really spent time with mine either. I had it running briefly for diagnostic purposes, but my 6.3VDC supply had issues. Got all that resolved, but I'm waiting for my case to be finished. It was at the plating shop last week, just needs to be laser engraved now and I can finally finish this project.