I am starting to believe that all depends on the pc and components. I did not feel anything special, but with the card, at some music passages, the details were not as outstanding as they normally are...

Alain

Peter, the most important thing is that you demonstrated that this tweak could be unstable depending of the resonance and the "blanket" sound that was happening.

Even if I don't trust my ears (and have said it frequently enough), there was something "soft" with the card. I was not sure if it was for the better.

But it worthed the attempt for the price. And sometimes it helps resolve a problem, would it be simply because it indicates another direction for investigation.

Alain

I wonder if such proximity with this device could generate a ground loop that would trigger sleep ?

Audiophile headrest I like that !

Alain

I experienced some problems when I first used the iUSB power supply with my USB cable (Mapleshade Clearlink 3 foot USB cable). Since the iUSB requires 2 USB cables, I was also using the 18 inch blue cable that comes with the iUSB. I could not use the following configuration: PC > blue cable > iUSB > Clearlink > Audiophilleo... Either there was no sound or after a few seconds I got "white noise".

I wrote to support at iFi-Audio and I was told that many "audiophile grade" USB cables do not have the correct impedance characteristics that is needed (90 ohm). Their suggestion was to use a standard USB cable instead.

With the Clearlink connected between the pc and iUSB and the blue cable between iUSB and the Audiophilleo, all was good. But I always wondered if using 2 cables + 2 more connections was a good thing or not. For this, the Aqvox way of doing things seemed better to me, even if the ripple figure was not as good as the one from the iUSB. 

With the NOS1, since there is not real need for power, I preferred not to use the iUSB. The simpler path, the better...

There is something that the iUSB brings with its "clean power". With it I can power a 2.5 inch SSD in an external case (it only requires 5V). I can also replace the power that is sent from my Sotm USB 3 PCIe card to the NOS1 (a USB > DC cable is also provided with the iUSB). I would like very much to have an external power supply that would feed my pc fans and another one for my music hard drive (external enclosure actually powered with a standard switching psu wall wart). My aim is to get rid of all the "contaminated" power that can affect other components and bring noise in the signal.

All of this brings me to a conclusion: XXHE and the NOS1 are BY FAR the 2 components that improved SQ to my system. There is nothing subtle about this. I don't write this because I am here in the Phasure forum. I can only state the obvious.

Alain

Thanks

Yet I thought the iUSB only goal was to provide a clean power for components requiring the USB power ? There is also that "Iso-Earth" thing, but I am not sure if it is intended to stop potential ground loops ?


Alain

Well, I am still wondering how the iUSB would do any good when coupled with the NOS1... I would like to read what Peter will say about my questions a few posts back...

Alain

Hi Juan,

It would not be a good idea to use the iUSB for that purpose... Like you mention, it would be at the USB 2.0 speed (not good).

Alain

Juan,

My apologies, I did not express myself well... By "components", I meant the fan that you removed on the top of the pc case, plus the filters for the bottom fans and maybe somes covers that you also removed (that the picture does not show)... Apart from the necessary components (CPU, memory, passive video card, sotm USB card and Xaudio card), I have not much inside the case... Maybe the fact that my case if covered inside with insulation material (I do not have a plexiglass window) does not help for the better flow of air...

Alain

Hi Juan,

I think that the fact that you removed some components helps the flow of air to better circulate (it's a guess on my part). The removal of the filters at the bottom may help...

Since I don't have much components inside the pc, I hope that a fan VR controller would improve things, at least eliminating the need for a PWM.

I was told that iFi-Audio (the makers of the iUSB power supply) have the intention of offering other power supplies (with different voltage) and since the iUSB has very good specifications, I am interested in having another power supply specifically for the fans (in a near future).

Regards,

Alain

No problem Since my English is quite limited, my interpretation was wrong The NOS1 made such improvement that at this point I did not felt it was useful to try it, but I will.

I have 2 problems though: my hearring abilities does not really help me (and this is quite a problem when I try to verify if something added or substracted something in the SQ) and I tend to get things that "could" improve something. So now I have a "collection" of components: Aqvox (not in use for the moment), iUSB, Sotm USB 3 PCIe card and the last (just before I bought the NOS1) is the Ultrafi Aubisque USB filter... Not to mention the recent acquisition of the PCIe XSound card (re:http://www.phasure.com/index.php?topic=2551.0).

I have yet to find a few songs that would help me distinguish the different properties of these components alone, then eventually combine them...

This struggles with my perception that a signal path should be as simple as possible, but you don't know if something will be of some help before you try it...

Regards,

Alain

PS: About the Aubisque, I had to order also a 90 degrees angled USB adaptor to allow the connection with the NOS1, since it was not possible to connect without risking to damage the connection itself (the USB cable crosses the analog interconnects and the Aubisque + the end of the USB cable make this too difficult).

Peter, when you mention "data domain" as opposed to "audio", I am not sure how to interpret this ? Do you mean that "data" is the signal before its arrival in the dac, as opposed to "audio" being the signal after the DA conversion ?

Here is my limited understanding:
- The power coming from the pc is replaced by a cleaner one from the iUSB (like the Aqvox, but better).

- Since the NOS1 does not really uses this power, it would not  have any effect on the quality of the transmission at this point.

- The data is not isolated, unless the "Iso Earth" feature has a positive impact on the data by breaking the ground noise ?

Alain

Oops, I would not go that far Too much risk of breaking something for the non DIYer that I am....

For sure though, the iUSB was good with the AP2 and I expect that any component normally taking its power from a PC USB port will certainly get better with the iUSB. This was audible, even for the "not that sensitive" hearing guy that I am

Alain 

Yes Peter, this was my thought (that the NOS1 did not require any use of the USB power for powering something) and the iUSB does not filter anything on the data side.

With the Audiophilleo the iUSB was very useful...

I could be wrong but I think that the simpler the path between the PC and the NOS1, the better (for the NOS1 at least).

Alain

Peter,

I am not sure if yout remark is aimed toward the addition of the iFi iUSB power supply, but my experience with it was different when I was using my Bryston BDA-1 DAC with an Audiophilleo. While the sound had no edges, I felt that the bass was a littlt "thinner" than the Aqvox I was using prior to the iUSB power supply. The Aqvox (first), then the iUSB were used to power the Audiophilleo USB to SPDIF then. Now that I have the NOS1, I use the iUSB to power my external SSD drive.

Have you seen the specs about the iFi iUSB ? It seems that it is even quieter than a battery...

Alain