Hi All,

I just thought that I would add an update to let you know where things are up to with the Linear ATX Power Supply.

Several options for assistance with the development of this project have been considered and weighed, from using an amalgamation of off-the-shelf power supplies to lots of help from afar from Peter and many things in between.  As Peter has realised from our email correspondence, not only do I like to do things right but I like to get them right the first time and I also tend to err on the side of overkill as well.  I will happily spend extra time to make sure that I get things right first time rather than rush the project.  So with that in mind I have enlisted the help of a friend that is an Electrical Engineer with a rabid passion for audio, especially the diy variety, who has his head screwed on and is not prone to fads and audio mysticism.  In effect I am the ideas man and my 'partner' in this is the brains that will get it working properly.

We have corresponded a lot so far on this project, often several times a day with ideas and ways to get past certain limitations but have come up a basic plan.  Design has started on the PCB's for this project and good progress is being made.  All in all this equates to an awful lot of time and effort but hopefully at the end of it there is a power supply that improves PC audio.

The basic idea as it stands right now, it to have a primary PCB for the 24 Pin ATX socket of the motherboard.  This will have three rails (12V/5V/3.3V) and will also include all of the logic for proper computer startup and shutdown.  This PCB will also be able to control up to five satellite power supplies that may be used in other parts of the computer i.e. P8 CPU and SSD/HDD and USB3 card and optical drive et cetera.  In the end, the computer will turn on and off the exact same way that it does now, but there will be a very high quality, reasonably modular, and reasonably intelligent linear power supply. 

We are going with largely SMD components in an effort to keep the size down but at this stage it is unknown whether we can get this to all fit inside the XXHE PC.  It looks pretty close to me.  Fingers crossed.   


Cheers,

Anthony

Good news Peter.  I love these new settings and I love my 48 based music as well so it would be nice if they could be used together.  When is the new version due?

Regards,

Anthony

I did this test Peter and all errors are gone.  Note that I never had FIFO errors, only KS/WDM errors.

Anthony

Interesting off-topic story here...sorry.   

One of my very good mates lived in Canada for a few years and ended up on an exploration crew in the oilfields north of Edmonton.  When he left up there he had some -30 degree temps.  When he got back to Australia he went straight out to the Moomba Gas Fields in the middle of the desert and experienced +50 degrees.  Quite a culture shock at both of these places especially when the 80 degree swing was experienced in the same week!!

Anyway, back to normal programming.

Anthony

Peter, the clicks are quite easy to hear and vary in size from barely audible to a little pop like vinyl to a temporary almost complete silence where a lot of data is lost.  Looking at the Phasure Driver Control Panel the errors show up about a second or so after the irregularity is heard.  The individual errors vary in size from 1 to about 1200.

I will look at the SFS stuff later on.

Anthony

You got me there...I will ammend my sig.

Peter, I should point out which settings were changed to get to these new settings...

xQ1 from 10 to 1
Q5 from 5 to 1
SFS from 20 max 20 to 2 max 8
Thread Priority from Realtime to High
Processor Appointment Scheme from 4 to 3
Xtweaks from 45/100/1/1/1 to 53/100/1/1/1

I have tried changing these settings individually back to their originals but I have not tried setting more than one of these back to their originals at the same time.

Also, I have the 8-core Xeon processor and not the 6-core i7.  Likewise, I am using the PPAstudio USB3 card.

Anthony

I've never heard this before, not once.

BTW, I'm loving the sound so far.

Hi Peter,

I have some issues.  Hopefully they are easy to fix.

As I played more music this morning I noticed some small clicks and pops coming from one particular classical track.  I replayed the first minute or so of this track several times and the clicks and pops were irregular, random, they happened at varying frequency and in varying spots in the soundstage (this audio gear is mad...I could point to where the pops were happening).  Anyway, I re-read your first post here and I tried playing with every changed setting (only one at a time) and could not get the pops to go away on this track, so it was time to think outside of these changes to see if I could pick up another pattern.

Here is what I found...the sample rate determines whether a track is going to have pops and clicks.  I went through much of my hi-res collection and played the start of one track from each single album, noted the sample rate, and in "attended mode) I kept track of the "Kernal Streaming / WASAPI (WDM) Error Count" in the "Phasure USB Control Panel".  The only errors that occurred where in that box.  Below is a summary of my findings...

Sample Rate	Result	# of Albums
16/44	Good	lots
16/48	clicks	1
24/44.1	Good	2
24/48	clicks	1
24/88.2	Good	2
24/96	clicks	5
24/176.4	Good	3
24/192	clicks	6
24/352.8	Good	2

Can you make any sense of this Peter?  Mathematically, I would say that the best correlation for the sample rates that produce clicks and pops is when the sample rate is neatly divisible by the bitrate eg. 48/24 = 2 or 192/24 = 8 or 96/24 = 4.  Is it that straight forward?

Regards,

Anthony

EDIT:  Thanks to Alain (and his post below) I have added the 16/48 sample rate to the table above.  Definitely have problems with sample rates that are a multiple of 48 with these new settings.

Hi Peter,

Initial impressions are very good.  I've only had it going for half an hour but I do like it so far.  I will put plenty of hours with these settings before I give my full report...but I'm loving the 'togetherness' that I am hearing, but I don't know whether that is the settings or the fact that it is raining right now and everything sounds better when it rains (at least it does over here in Australia where it tends not to rain for long periods - the blue skies and sunshine get monotonous after a while hehehe).

Cheers,

Anthony 

Thanks for the report Nick.  The particularly interesting part for me is that you report that the "tone" has changed...if what I call tone is the same as what you call tone then this is a profound change.

My major gripe with an external clock such as the DEXA is that it is removed from the USB board and the clock signal must travel by wire a certain distance to where it is required and hence becomes more sensitive to inducting noise.  Two steps forward...one step back.  The ideal way here would be to incorporate something like the DEXA clock into a redesigned USB board, but only Peter could manage that sort of an upgrade.

I really look forward to Pauls impressions once he has his DEXA clock installed.

Anthony 

Thanks Peter,

The atx power solution I have been working on should manage the shutdown process properly by intercommunication between the power supply and the mobo.  I say should, because I don't have a working prototype just yet...

Anthony

Hi Peter,

I've done the server 2012 thing with jplay before coming across to the nos1 xxhe combo.  Server plus phils software really worked well for what it was but I must say that you are well ahead with your software Peter and the way that it manages the pc.  There is zero need for server in my opinion.  The thing that I am enjoying here is the balanced, thoughtful approach to improving digital music reproduction.

Cheers,

Anthony

Of course...I did not even think of the existing connection for the Molex plug.  So probably yes, the 900mA (top end of USB3 spec) for the USB port may well come from the Molex plug.

Hi Alain,

I am having a look at the V2 PP card and I don't think that the 5V for the USB port is generated from the Molex plug, I think that it comes from the PCIe port.  Power goes directly from the Molex plug to the clock (which is the yellow board that is offset mounted) and I see no sign of anything other than the clock signal going to the usb card itself. 

Regards,

Anthony