Hello.
Immediately - I ask you to forgive, English is not my native way to Express thoughts, so please do not look for hidden meaning in my posts
I recently became the owner of a set of AudioGD devices
R7HE (2019) and HE1
Before that, the Exogal Comet Plus DAC worked in my system for a long time.
Just as long in the system was Soundaware D300Ref, which suits absolutely everyone.
It was connected to the DAC from Exogal via the AES interface. There were no problems. Played any of the available formats, except DSD native. Since my DAC does not accept it via the AES interface.
It was decided to connect the new DAC directly to the D300Ref via the i2S interface.
But what a disappointment it was when I heard noise instead of music at the beginning.
Yes, almost immediately I realized that the problem can be solved by switching the input to the DAC several times, 2-3 times was usually enough, the problem disappeared, and the format that was played did not cause failures. But as soon as I switched from PCM to DSD, the noise would reappear.
Another connection method (AES, Coax) solved this problem completely, the noise does not appear on these interfaces under any circumstances, but the sound quality is noticeably inferior to the I2S interface.
Just note that I connected the equipment with a fairly short HDMI cable, only 50cm. and its quality did not cause any questions, just in case I took a known working cable for a while, but the problem was repeated with it.
Before purchasing a DAC from AudioGD, I tested Soundaware with a single DAC over the i2S bus, and there were no problems.
Also, after detecting the problem, my friend helped me check the DAC operation on the I2S interface with its Audio-GD DI-20HE Converter, and again there were no problems.. once, there was a minor squeak, but the systemic nature of the problem has not been worn.
To solve the problem, I tried changing the firmware to D300REF, but it didn't work.
I tried to change the firmware on the DAC, and then I realized that almost all of them give a different effect, relative to my problem.
As you know, there are several firmware versions: synchronous and asynchronous.
(From the description on the site: Synchronous use the MCLK of the transport device, asynchronous use the internal CLK generator). Firmware has a common code for a number of R2R devices.
So:
R-7_V3 (Jul. 2018), the very first, asynchronous version, does not cause noise when switching PCM-DSD, There is no noise after initialization, but often breaks down to noise in PCM formats 176-192 KHz. In terms of sound quality, questionable firmware.
R-7_tda (Apr.2019), there is no noise when switching PCM 44.1/16bit to DSD, but there is constant noise in 24bit records, this noise does not disappear when trying to switch inputs to DAC.
R7tda_Asy_P_rmdsd_dop (July.2019) and R-7_P2_DSDCLK (Oct.2019) both behave the same, the noise when any signal is applied to the input immediately after switching on, it can be fixed by switching the DAC inputs, at some point there is a sound, but when you send a signal to the DSD, the noise returns, you can remove it by switching the inputs. By the way, DSD Native on these firmware is not played-NOISE, remove switching inputs is not possible.
Firmware R7tda_Asy_P_rmdsd_dop produces the best sound quality.
Further... I write letters to manufacturers.
Mr. Kingwa of Audio-GD, in fact, was the first to respond.
In short, his answer is that Soundaware does not produce an accurate signal, so the DAC can not always catch it, and in the new DAC firmware, the accuracy is improved and all timings are tightened. this makes it even more difficult to lock a bad signal.
He asks for a real diagram of the output signal of the i2S D300, and wants to make sure that the phase of the signal is correct.
Soundaware wrote with a big delay, complained about the raging virus. They say that we do not work because of it, we recommended checking the compatibility of interfaces by pins. Well, they're sort of compatible, and Mr. Kingwa and I checked it out.
Actually... I have a question to users: Perhaps someone has a Soundaware D300 / REF and AudioGD DAC connected via the I2S interface, how does it work for you? Are there any bugs?