SIRIUS G2 discussion and questions


SIRIUS G2 is a very unique device, the function and the performance has never being achieved before. Please post your question and discuss this product within this thread.

SIRIUS G2 Press Release
AURALiC Debuts SIRIUS G2 Upsampling Processor at Munich High-End 2019

Official press release:

Product flyer:

Technology explanation keynote:



hello Xuanquan,
if I understand correctly, the Leo gx reduces the jitter to 0.
if I read the presentation of Sirius, it is mentioned that his interest is reduced the jitter.
so, should I understand that when we are equipped with the vega g2-leo gx combo, the sirius becomes useless.
indeed, difficult to reduce the jitter below 0, is not it? :grinning:

can you tell when it will be possible to make convolution with sirius and if auralic will develop sirius-specific acoustic correction settings. because if I understood correctly, the possibilities of parametrage will be at the beginning identical to those of the aries.

thank you !


Can you downsample DSD and PCM as well ? For people that have DAC which are limited to DSD64 and have files on DSD128 or 256 ?

Like roon, dsd is not converted to PCM ?


@Xuanqian can I ask the question that a lot of us will be thinking, what does the Sirius do that betters HQ player.

From reading the press releases this is what HQP was designed to do. What (how) does the Sirius do better?

This is a serious question, I own an Aeries and am currently feeding it with Roon. I could get a Sirius in the mix or use HQP to feed the Aeries. From reading all the linked documents I cannot see an obvious reason to go to Sirius before HQP.



No need to have a pc to do that … simplier to use and more stable (no windows or os to patch etc …). Nothing to install or configure etc …
But it’s not the same price too :slight_smile:


To answer questions at once:

1, Regarding the jitter elimination feature. The VEGA G2 and Lightning Link have been designed to work in a jitter free way so the jitter elimination feature of SIRIUS G2 is not important at this point. Your major benefit is upsampling to DSD256/DSD512 which make VEGA G2 sounds much much more smooth. Since this product has been designed to work with all DAC, I would except other DAC will benefit from this feature.

2, Convolution engine is still in early research stage, the way how it will work is to ask user to import several response wav files (for different processing sampling rate) and apply to the DSP. You still need to use your own software to generate this impulse response file.

3, The ‘Upsampling’ feature can convert any sampling rate to any sampling rate, up and down, without limitation. Please remember that converting DSD to another DSD will need software to internally convert 1-bit DSD to multi-bit signal (not necessarily the PCM you are familiar with) then back to another 1-bit DSD rate. Such operation does not mean you are going to lose any resolution if processed properly. Unfortunately most of current software running on PC can not convert without degrade the original sound quality, SIRIUS G2 however wont.

4, SIRIUS G2’s DSD upsampling algorithm is very sophisticated and requires a calculation ability beyond what current PC can do, that’s why we end up with FPGA solution. To run the same algorithm on current x64 computer (upsampling any PCM to DSD512), you will need a 4-way Xeon server with each CPU has approx 12 cores. It offers converting resolution and sound quality beyond any software available today.

Auralic Sirius G2, Q&A

Thanks for the informations !


With these PC based systems there are many choices of filters and dither/ noise shaping options as well as sampling rate. Personally I find the choice overwhelming.
What level of choice / options does Sirius give?




Having looked through the press release on Sirius G2, i noticed it’s Ethernet port on the back.
Does the Sirius come with similar streaming abilities as the Vega does? (That would mean basic streaming abilities, like Roon Endpoint and option to be controlled by Lightning DS when there is an existing UPnP on the network)
And i could use it to serve my Nagra DAC with DSD128 from each and every source input, if i desire?


Ethernet port is for software update.

You can upsample to DSD128 on each input. But the output must support it. So USB only or lightning link


Like all other product, we provide a set of four filter settings for customer to choice.


Unfortunately the Ethernet is for OTA update only, this device can not do any streaming at least for now. You really need another device in the front and plug into SIRIUS G2’s USB input. If you just use Roon, think about to add a RPi in the front if you know how to install the Roon code on it.

Regarding the output, as long as you have configured the output sampling rate, the device will convert all input signal at all sampling rate to DSD 128 and feed to your Nagra.

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This raises a question for me.
I currently run the Vega G2 plus Leo GX and run Roon on a Mac mini. Roon feeds the Vega as an endpoint.
I love the Sirius concept, but where would it fit in this configuration? The Sirius needs to sit between the music source and the Vega. Will Sirius be Roon Ready? If not, I cannot see how I can make this work (unless I buy an Aries G2 as well??).
Do I understand this correctly?


Yes, you need a source connected to the sirius


The Sirius has got all the inputs of the Vega, but for the streaming parts. That means you could connect your MacMini to its USB-input and enjoy the sound of upsampled audio.


Hi, thanks for your input.

My concern however is whether I be able to use Roon? If Sirius is Roon Ready, no problem; but if not, I’ll not be able to use Roon. One of the reasons I went with the Vega G2 is that it is Roon Ready (as well as its brilliant performance).

I’ve not seen any reference to whether Sirius is, or is not, Roon Ready. Most of Auralic’s products are Roon Ready so there is some prospect that Sirius is also, but the fact that there’s been no comment on this I’m thinking it might not be. Before I spend $6k, I’d like to know, though I think deuch has answered the question.


Xuanqian answered too :grin: you need a source connected to the sirius. an aries mini can do the trick or other solution.

The sirius will stand between the source and the dac.


Yes, I understand. If I want Sirius I can no longer use the Vega G2 as streamer. I need something else to stream to Sirius and from there to Vega.
How about a software upgrade to Vega that diverts the streamed signal via Lightning to Sirius for processing and then back to Vega for output?
Ah well, one can only dream.