The M19 uses an RJ45 digital output.
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Can it work? I believe Bricasti uses the standard IIS protocol rather than the LVDS.
I have read before that Bricasti (Brian Zolner) have stated they use the PS Audio standard.
The output of the M19, as stated here before, is an RJ45 plug. Maybe you could make a cable that has the RJ45 on one end and the HDMI on the other?? If so, maybe that would work with our MSB DACS? Doesnât seem like an Insurmountable problem but what do I know?
Some of the transport/DAC I2S connections are also meant to provide copyright protection pertaining to Sonyâs SACD licensing.
Bricasti states: âThe M19 also offers a proprietary I2S digital output to be exclusively used with Bricasti DACs.â
Hence, it might well be that the connection issue is not just about correctly wiring an RJ45 with HDMI plugs, but there might be protocol data or other mechanisms that prevent the M19 from sending native DSD to a non-Bricasti device.
I believe that I2S circumvents the SACD licensing issue by being an INTERNAL protocol. As such anybodyâs I2S could be considered proprietary. There is no real I2S external standard, which is probably why the licensing issue can be circumvented in the first place. MSB has developed a flexible I2S interface that can be adapted to different manufacturersâ I2S signaling conventions where HDMI is used as the I2S physical signal transport. Iâm guessing that MSB could have chosen to use RJ45 (or HDMI and RJ45) based on economics and anticipated demand.
I understand. Could that also be true if they state they are using the PS Audio protocol?
Every single âI2Sâ device I have seen so far sends different protocols over the same wires. There are hundreds of possible combinations and each manufacturer seems to have deliberately or by accident introduced minor differences that even they may not notice, but are significant if you want the best quality. For example a couple of products that use the âPS Audioâ format invert the data lines. This still plays back music but in the opposite phase from other sources. Or an interface that works properly at most sample rates, but not one or two. Or an interface that swaps the left and right channels. Or an interface that changes the polarity only when in DSD mode. Or an interface what requires different signaling to enable DSD mode. Or an interface that glitches when switching sample rates. In the end we have to uniquely program every single I2S interface to match what is actually happening on it for it to work properly and seamlessly.
The RJ45 âI2Sâ interface again can have all of these quirks but also signal level differences that can burn out the electrical drivers or receivers, which means the same jack could require completely different physical circuitry. If the wrong source were connected to the wrong circuitry it could kill the transport or input card.
The current I2S works by having a large number of configurable logic blocks and crossbar switches that under software control can rewire and reconfigure the interface to make it compatible with whatever transport is connected to it. I begin by measuring the position and polarity of every signal in every format and programing them. Then we test the polarity of the audio DATA for every format to make sure the phase is correct and invert the phase where necessary. Then test left and right for every format and program those into a table. Then determine the sideband signaling wires to determine the correct communications and program them. Then test for various glitches and enable and configure the correct anti-glitch circuitry for that particular interface. Then make a table of unsupported or malfunctioning formats for that interface and create a table to mute them to prevent catastrophic problems, like the playback of full scale DC or white noise.
It is extremely important for you to use the correct programmed settings for the transport that you actually have and not âexperimentâ to see what works or what you prefer. With some of the outputs from some transports it could result in major glitches that could blow up speakers or amplifiers. It is also why the I2S interface is disabled by default until you select your particular transport from the menu.
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Thanks for jumping in Jonathan. Itâs all Greek to me.
The takeaway is that there is no âI2Sâ standard at all, every transport is different, each transport needs to be individually evaluated and programed, and supporting the RJ45 interface, outside of a closed system, is not viable and would result in a lot of broken product.
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Thank you, Dustin.