[drez]

Quote:

BTW, 6moons posted all the schematics required in order to hook up a clean PSU to a USB cable: http://www.6moons.com/audioreviews/kingrex12/1.html
 
It very much works, and it's done wonders on my rig 

 
I'm considering doing a similar setup in my system, only I need a spare power outlet, and I'm not certain the improvement will be worth it if purepower is already in use, but still it's on the drawing board.
 
One thing I tend to notice with the AP2 is that it is more prone to dropouts when the CPU is under load for example when gaming than other adapters, I'm guessing its the buffer underrunning or something.  Similarly large changes in CPU load can throw the buffer out in Windows as well.  I might need to keep the JKSPDIF mk3 for gaming, but it seems a bit of a waste and a hassle, as well as an extravagance.  Anyhow what can you do...

 

[leeperry]

Quote:

Anyhow what can you do...

 
Use a media player that allows you to set its audio thread to realtime priority(Reclock for instance)? That's what I do...the XMOS doesn't drop, even if I play music via ASIO+VST plugin while playing very demanding video simultaneously.
 
You can also increase the priority of the audio rendering threads in W7/W8 and lower all the rest to "idle"(using a process.exe batch when Windows starts, that's what I do). You may also wanna give a shot to Fidelizer if you're not using it yet.
 
Don't blame your transport if your OS is slugglishly set up as it's rather notorious that the OS from m$ are not audiophile friendly if you don't modify them.
 
To get back OT, my 5V/1A linear regulated PSU has literally skyrocketed the SQ of the XMOS, everything has gotten so much clearer: SS 3D'ness, deep bass, everything 

 

[drez]

Quote:

 
Use a media player that allows you to set its audio thread to realtime priority(Reclock for instance)? That's what I do...the XMOS doesn't drop, even if I play music via ASIO+VST plugin while playing very demanding video simultaneously.
 
You can also increase the priority of the audio rendering threads in W7/W8 and lower all the rest to "idle"(using a process.exe batch when Windows starts, that's what I do). You may also wanna give a shot to Fidelizer if you're not using it yet.
 
Don't blame your transport if your OS is slugglishly set up as it's rather notorious that the OS from m$ are not audiophile friendly if you don't modify them.
 
To get back OT, my 5V/1A linear regulated PSU has literally skyrocketed the SQ of the XMOS, everything has gotten so much clearer: SS 3D'ness, deep bass, everything 

 
Interesting tips - I haven't used reclock for some time but no doubt it's worth it for video.  I think I found some bogs running ASIO4ALL with the AP2 (the ASIO session would not shut down like it normally would) so hopefully glitches were related to this.  Do you have a link (or example) of how to set up the batch file for thread priority?  I might just try lowering browser priority as that seems to be the biggest resource hog when I am typically running music in the background.  I'm not blaming AP for the dropouts - just noting that I have encountered differences between it and the JKSPDIF (most notably in terms of setting up buffer length in playback settings) which I did not encounter previously for whatever reason (maybe HiFace locks the buffer in the driver or something?)  With gaming hopefully I find that the dropouts are to do with the ASIO4ALL bugging up so I can sell my JKSPDIF (although I keep it in case AP insist that I ship my purepower back to fix the loose battery.)
 
I might bring up some of those tweaks with the JPlay ppls in case they have any thoughts on whether their own tweaks overlap, but I think they still will probably be useful as the JPlay doesn't seem very invasive in terms of changing other programs (apart from when it hibernates windows)

 

[leeperry]

You want to read "The art of building Computer Transports v0.3.pdf", most of it is magical thinking but there are also some great advices in there.

 

[drez]

Quote:

You want to read "The art of building Computer Transports v0.3.pdf", most of it is magical thinking but there are also some great advices in there.

 
Cheers mate! 

 

[Rdr. Seraphim]

Back to the AP/PP discussion 

 ...and now adding the VAUNIX Lab Brick USB Hub.
 
I received the VAUNIX this a.m., after watching it via the Internet trek cross country. It was like a watched pot that never boils... 
 
My opinion? If you have an Audiophilleo 1 or 2, and the VLN Pure Power battery power supply, get the Vaunix too! What a surprise! In my system, the Vaunix definitely takes SQ up several notches. After a few hours of operation I'm surprised how warm it is to the touch. 
 
More later...  

 

[Trogdor]

Back to the AP/PP discussion :wink_face:  ...and now adding the VAUNIX Lab Brick USB Hub.

I received the VAUNIX this a.m., after watching it via the Internet trek cross country. It was like a watched pot that never boils... 

My opinion? If you have an Audiophilleo 1 or 2, and the VLN Pure Power battery power supply, get the Vaunix too! What a surprise! In my system, the Vaunix definitely takes SQ up several notches. After a few hours of operation I'm surprised how warm it is to the touch. 

More later...  

I am bit skeptical. What is the Vaunix giving you again?

 

[Rdr. Seraphim]

I'm sure it's all placebo 

 . Not sure it's giving me "anything," but it robbed my wallet of a couple hundred dollars. YMMV of course, and it's just my opinion, but adding in the Vaunix provided a level of transparency that was not obtainable with the AP/PP alone. I was skeptical too. After all, the USB and processor are supposed to be isolated from the PP battery powered clocks. Apparently, that's not all there is to it. It made a difference in my system, a substantial difference. 
Quote:

I am bit skeptical. What is the Vaunix giving you again?

 

[Currawong]

The Vaunix is a hub for their signal generators which require a clean power supply, better than what a computer gives out.

 

[DaveBSC]

Quote:

I'm sure it's all placebo 

 . Not sure it's giving me "anything," but it robbed my wallet of a couple hundred dollars. YMMV of course, and it's just my opinion, but adding in the Vaunix provided a level of transparency that was not obtainable with the AP/PP alone. I was skeptical too. After all, the USB and processor are supposed to be isolated from the PP battery powered clocks. Apparently, that's not all there is to it. It made a difference in my system, a substantial difference. 

The AP2+PP is still using SOME Vbus power for the USB input circuitry. The Vaunix is helping to clean that up. Clean power is always better than dirty power. Another option would be to try one of those pricey Y-type USB cables, with the power leg connected to something like the Kingrex uPower.

 

[Rdr. Seraphim]

If cleaning up the Vbus power provides this much change, I'm all in for more! Not sure I'll go the Kingrex uPower and the "pricey" Y-type USB cable though... if I do anything more it would be an altogether different direction, e.g. Empirical Audio, if I can get an audition. For now, what a difference the Vaunix hub provides. 
 
Quote:

The AP2+PP is still using SOME Vbus power for the USB input circuitry. The Vaunix is helping to clean that up. Clean power is always better than dirty power. Another option would be to try one of those pricey Y-type USB cables, with the power leg connected to something like the Kingrex uPower.

 

[DaveBSC]

Quote:

If cleaning up the Vbus power provides this much change, I'm all in for more! Not sure I'll go the Kingrex uPower and the "pricey" Y-type USB cable though... if I do anything more it would be an altogether different direction, e.g. Empirical Audio, if I can get an audition. For now, what a difference the Vaunix hub provides. 
 

The Off-Ramp is completely self powered, so there'd be no need for battery power of the 5V line - it isn't used. Cutting it off though can help, Steve mentioned that his products sound better through his Short Block device which is an inline USB filter that also cuts the Vbus line. The Lab Brick might also be beneficial, as it benefits the data stream as well. Perhaps that's also providing a boost to the AP+PP.

 

[drez]

I though Vaunix doesn't change D+ and D-?  Either way I think I might go with batteries for the AP2 USB input, probably with a Y-cable.  I'm not sure though if the AP still needs to be connected to computer/wall outlet ground as a safety ground?
 
Vaunix seems a bit expensive for me at this point when any low ripple PSU will probably be an improvement (and I don't want to run extra USB cables), just I'm not sure if my spare wall outlet works properly so I might need to get that sorted out first or use batteries.  A few folks over on SNA have been working out battery power for the AP2 so I might keep tabs with that project.  To be honest though this is getting pretty close to the cost of an Off-Ramp once I order parts etc (even with paying import duties on the OR5) and from a few impressions that is meant to be well ahead of the stock AP2...  Ahh well it's something to keep me busy just wish it didn't cost so much...

 

[DaveBSC]

Quote:

I though Vaunix doesn't change V+ and V-?  Either way I think I might go with batteries for the AP2 USB input, probably with a Y-cable.  I'm not sure though if the AP still needs to be connected to computer/wall outlet ground as a safety ground?
 
Vaunix seems a bit expensive for me at this point when any low ripple PSU will probably be an improvement (and I don't want to run extra USB cables), just I'm not sure if my spare wall outlet works properly so I might need to get that sorted out first or use batteries.  A few folks over on SNA have been working out battery power for the AP2 so I might keep tabs with that project.  To be honest though this is getting pretty close to the cost of an Off-Ramp once I order parts etc (even with paying import duties on the OR5) and from a few impressions that is meant to be well ahead of the stock AP2...  Ahh well it's something to keep me busy just wish it didn't cost so much...

From Vaunix:
 
We use separate power supply and digital grounds.  The grounds are both physically and electrically separated which prevents ground loops and prevents noise coupling.  The housing is all metal which eliminates any noise due to EMI. The data lines on the PC board are matched to a balanced 90 ohms impedance.  The best cables in the world won't help you if the data lines are not properly matched on the PCB. The use of balanced, properly matched lines provides common-mode rejection of noise resulting in a cleaner output.
 
The Lab Brick uses internal DC-DC regulation to get from 12V supplied by the wall-wart to 5V. Theoretically using a linear PS would further improve its performance, but that means spending at least another $400 or so on a power supply with at least 2A output. I don't know if anyone has actually tried it.

 

[drez]

I don't think a linear supply needs to be $400, as far as I know all one really needs is a transformer and a linear voltage regulator such as from AudioGD, Paul Hynes or Burson.
 
I'm still not sure I understand 100% what Vaunix does with the grounds still I guess its better than introducing a ground loop through the AP2 - is this even possible though if the AP2 has internal galvanic isolation?
 
I'm not entirely sure the AP2 needs a safety ground at all if it's only D+ and D- connecting to the computer?
 
I'm not sure linear supply will be necessarily better than switching with the Vaunix anyway especially if they have done a good job on the internal DC-DC regulator.  Still seems kind of expensive and bulky, especially when I am not a fan of putting anything extra between the computer and the D/D converter.  I would probably end up doing Y-cable with V+ and Ground going to the vaunix and D-, D+ to the computer which well is kind of like using any other power supply as far as I am aware?