I had the Hydra Z, too. Tested it with the Black Dragon and then I bought it for the DS DAC. Imho the Hydra makes much more sense together with the BD than with the DS DAC. I liked the Hydra/BD combo very much but unfortunately I didn’t like the Black Dragon as a preamp at all and for some reason, the BD didn’t work well as standalone DAC in my setup.
Well, I am happy with my Pi2/I2S streamer now. No need for the Bridge II here.
Holzohr : Was there any particular reason that you chose the PiCorePlayer over the other available options?
I am a Squeezebox guy for many years so the piCorePlayer with Squeezelite was the first choice. Another useful thing it is running entirely in RAM, so no harm to your SD card when you pull the power. The SD card is only needed for booting.
In my Raspberry I2s streamer project PiCorePlayers i2s-driver was only driver that first started to work! But after shut down green light in Directstreams touchscreen stayed lit, and then all the others (like Max2plays driver) started to work.
Hope this makes any sence, but I believe that without PiCorePlayers driver I wouldn’t ever get my Raspberry streamer to work.
Paul McGowan said
I2S is better than UDSB, certainly, but I do not know if those interfaces you mention will work.
Other than there being relatively few compatible I2S sources, is there any reason why one would not want to strive to use I2S if possible? Since I2S is essentially the native format for DACs, doesn't I2S simplify the process by eliminating extra digital conversion steps and eliminate the numerous potential issues with USB? I am trying to understand why I2S is not the clear way to go.
Really the differences at this level depend on your source and other attributes of your system:
From a theoretical point of view I2S wasn’t designed for long distances. Paul and I probably disagree a little but I attribute most of the I2S improvements on the DS (as opposed to other DACs) to the better grounding that I2S cables have rather than other things like potentially lower jitter or other differences. Indeed if one wants the simplest hardware one would use TOSLink. There’s literally just a TOSLink receiver module and a wire to the FPGA… TOSLink also has the advantage of galvanic isolation, so if it has the bandwidth you need you should at least consider it. AES/EBU and S/PDIF also avoid the worst theoretical problems from USB and their hardware is as simple as I2S, but the typical cables used for them both radiate more than I2S and also usually have much weaker grounds. Also, to beat a dead horse: when one is comparing one digital cable to another, one should disconnect any other digital cables that won’t be in your system for each test. Most of the noise/interference from a digital cable comes from ground loops, etc. so having multiple cables from one source to the DAC can mask potential benefits of one cable over another.
Ted Smith said
Really the differences at this level depend on your source and other attributes of your system:
From a theoretical point of view I2S wasn’t designed for long distances. Paul and I probably disagree a little but I attribute most of the I2S improvements on the DS (as opposed to other DACs) to the better grounding that I2S cables have rather than other things like potentially lower jitter or other differences. Indeed if one wants the simplest hardware one would use TOSLink. There’s literally just a TOSLink receiver module and a wire to the FPGA… TOSLink also has the advantage of galvanic isolation, so if it has the bandwidth you need you should at least consider it. AES/EBU and S/PDIF also avoid the worst theoretical problems from USB and their hardware is as simple as I2S, but the typical cables used for them both radiate more than I2S and also usually have much weaker grounds. Also, to beat a dead horse: when one is comparing one digital cable to another, one should disconnect any other digital cables that won’t be in your system for each test. Most of the noise/interference from a digital cable comes from ground loops, etc. so having multiple cables from one source to the DAC can mask potential benefits of one cable over another.
Oops, I have just done a bunch of comparisons of the digital inputs and tend to always leave the inactive cables in. Are the "inactive" ones active anyway even if nothing is playing through the source just by being plugged in?
Also, if I have a source that is active but running to one DAC by SPDIF and another by TOSLink at the same time or USB, does that create problems? On my streamer, I have to select either USB or other digital outputs and only one of them works.
Also, if I have an ethernet cable plugged in (non optically isolated) to my streamer but not active since I use 802.11 ac wi fi instead, does this matter?
yacheah said
Oops, I have just done a bunch of comparisons of the digital inputs and tend to always leave the inactive cables in. Are the "inactive" ones active anyway even of nothing is playing through the source just by being plugged in?
Also, if I have a source that is active but running to one DAC by SPDIF and another by TOSLink at the same time or USB, does that create problems? On my streamer, I have to select either USB or other digital outputs and only one of them works.
Also, if I have an ethernet cable plugged in (non optically isolated) to my streamer but not active since I use 802.11 ac wi fi instead, does this matter?
It's not really a problem with function, etc. It's just that every cable causes another set of ground loops. The flux thru each ground loop causes a current to flow around that loop which can subtly alter any signals in that loop. So each additional cable (whether there is any signal at all in it) can add a possible source of noise pickup in all other cables (including power cords) connected between the new cable's source and it's destination. As you system gets better and better these small effects become a bigger and bigger part of the noise that's left in your system. A TOSLink cable doesn't add to the problem, but any other unused cables connected may be causing extra noise with other parts of your system that hide the lack of noise from the TOSLink cable.
I wouldn’t get carried away with plugging and unplugging cables every time I listen. But it may be worth it when you are doing explicit A/B’s and or taking the time to tune your system. (I don’t remove all extra cables every time I A/B or even often when I’m just listening, but it’s really hard to tell the exact effect of replacing a given cable if that old cable is what’s making your system sound better or worse than your system would be with that old cable gone.)
It’s not really a problem with function, etc. It’s just that every cable causes another set of ground loops. The flux thru each ground loop causes a current to flow around that loop which can subtly alter any signals in that loop. So each additional cable (whether there is any signal at all in it) can add a possible source of noise pickup in all other cables (including power cords) connected between the new cable’s source and it’s destination. As you system gets better and better these small effects become a bigger and bigger part of the noise that’s left in your system. A TOSLink cable doesn’t add to the problem, but any other unused cables connected may be causing extra noise with other parts of your system that hide the lack of noise from the TOSLink cable.
I wouldn’t get carried away with plugging and unplugging cables every time I listen. But it may be worth it when you are doing explicit A/B’s and or taking the time to tune your system. (I don’t remove all extra cables every time I A/B or even often when I’m just listening, but it’s really hard to tell the exact effect of replacing a given cable if that old cable is what’s making your system sound better or worse than your system would be with that old cable gone.)
Thanks for that. I was going to say it must be a nightmare especially for you to have to plug and unplug all the cables. I probably have a lot less and already am sick of the mess behind my setup.
Some DS users locally have reported good results with this USB to I2S bridge/ adapter if you can call it that.
Blanket statements like “remove the USB noise” are an over simplification. That box is using the same tech as the DS, whether it removes more noise from USB will be system specific. Some people get great USB results in their systems with minimal work while others go to heroic efforts. Just as some get much better sound with the Bridge and others get better sound with USB. IMO pick the way you want to use the DS (or any DAC) then optimize your system for the way you use it. I prefer the user experiences that I get connected with USB so I concentrate my efforts there. Others prefer various UPnP control interfaces so they tend to use the Bridge.