Hello folks, a total newbie here. I recently ordered a Smyth Realiser A8, and while I'm excited by what it can do, I'm still perplexed about its choice of inputs. It has an HDMI input as its sole digital input (which I find strange, considering USB or S/PDIF is far more common in digital audio), and 4 pairs of RCA analog inputs.
1. It is my understanding that the Realiser's 3D surround sound conversion takes place in the digital domain. Does it mean that if it receives analog signal via its RCA inputs, there is an ADC (analog-digital converter) that converts the analog signal to digital before working its 3D magic? And if so, wouldn't it be better, in terms of sonic quality, to send a digital audio signal via its HDMI input (and thus bypass the ADC circuitry completely) for a purer sound?
From what I've heard, HDMI and Toslink (optical) aren't ideal choices for digital audio transmission, due to jitter (asynchronous USB is said to be superior in this regard). I was told that there aren't that many source components or music servers that provides a decent HDMI implementation for digital audio transmission.
2. That being said, what are some of the recommended ways to utilize the Realiser's HDMI input? I own an Apple iMac with Audirvana/Pure Music/Amarra that I use as my primary music server, and I'm considering using a Mini DisplayPort(Thunderbolt)-to-HDMI adapter and an HDMI cable to connect the iMac to Realiser. Will this work perfectly without any issues? But also importantly, even if it works, is this a recommended method in terms of sonic quality?
3. Some people seem to use the Oppo BDP-105 here. I did some research and it is a Blu-ray/SACD/CD player with multiple inputs and outputs. I'm guessing one could use its HDMI output to connect it to Realiser's HDMI input? Is this a better way to listen to music than the above method of connecting my iMac with an adapter?
4. If using the Oppo BDP-105 is better in terms of sonic performance, then is there a way to use the Oppo as a digital music server, like my iMac? I know it can play spinning discs, but I'm talking about nearly 500G of hi-rez digital audio files stored in a drive. In fact I store all my music collection not in my iMac but in an external hard drive connected via FireWire, the iMac solely playing the role of audio playback using its softwares (e.g. Amarra). I don't think there is a built-in drive inside the Oppo that could store music files; is it possible to connect an external hard drive to the Oppo and have it play the audio files inside it, sending it to the Realiser via its HDMI output? And is this also a recommended method?
5. Overall, in theory, what would be the best method in terms of sonic quality?
A) Hard drive > iMac (w/ Amarra) > Mini DisplayPort-to-HDMI adapter > Realiser > headphone amp > headphones
The sole method that does not require the Oppo BDP-105 at all
B) Hard drive > iMac (w/ Amarra) > USB cable (connecting the iMac to Oppo's USB DAC input) > Oppo BDP-105 > HDMI cable (connecting Oppo's HDMI output to Realiser's HDMI input) > Realiser > headphone amp > headphones
Using the Oppo BDP-105, but taking advantage of the high quality playback capability of Amarra. Technically, the Oppo BDP-105 simply works a bridge between the iMac and Realiser, a USB-to-HDMI converter if you will. I'm not sure if this method is even possible, though...
C) Hard drive > iMac (w/ Amarra) > Mini DisplayPort-to-HDMI adapter > Realiser > HDMI cable (connecting Realiser's HDMI output to Oppo's HDMI input) > Oppo BDP-105 > headphone amp > headphones
This method is the same as A, but instead of connecting the Realiser directly to the headphone amp, it connects to the Oppo's HDMI input (thus bypassing the Realiser's built-in DAC and instead utilizing the Oppo's DAC). Of course, this method would be meaningless if the Oppo's DAC isn't superior to the built-in DAC of the Realiser.
D) Hard drive > iMac (w/ Amarra) > Mini DisplayPort-to-HDMI adapter > Realiser > Toslink optical cable > Oppo BDP-105 (or any multichannel DAC with optical input) > headphone amp > headphones
This method is the same as C, but instead of HDMI this time we're using an optical cable. I guess it depends on which of the two. HDMI or optical, is a superior implementation for digital audio. Also, speaking of which, can Toslink transmit multichannel digital audio data too?
E) Hard drive > Oppo BDP-105 > HDMI cable > Realiser > headphone amp > headphones
In this case, we're not using the iMac (w/ Amarra). This method would be better, if 1) it is possible to connect an external hard drive to the Oppo and use the Oppo as a music server, and 2) Oppo's digital audio playback is superior to that of Amarra.
I know it is a long question, but I would appreciate feedback or answers from anyone who is experienced. Thank you in advance.