A novel way to massively improve the SQ of computer audio streaming

[Superdad]

Don't let the lack of any other devices stop you. This tweak (if you want to call it that) stands on its own merit. Even when I use my noisy Mac Pro which is not optimized for audio at all, the benefits of doing this are still very very obvious.

 

Glad to see you bringing up the topic of eliminating the Ethernet switch from your chain. What's old is new again. From a little over 3 years ago:

http://www.computeraudiophile.com/f27-uptone-audio-sponsored/uh-oh-i-beat-my-sd-card-trick%3B-bypass-your-ethernet-switch-and-make-your-external-drives-sound-close-ram-disk-using-apple-thunderbolt-ethernet-adaptor-and-second-network-connection-18475/

 

I must admit though, I have not yet tried or been successful with bridging (was fussing with ifconfig until you pointed out OS X's "Manage Virtual Interfaces" controls) such that I could directly connect my microRendu to run it as NAA for HQ Player. HQ Player is fussy about the NAA getting a DHCP-assigned IP address. So if I have the time to fidget with this again, that would be my goal.

 

I find my tweaked Mac mini (JS-2, beta-enchanced and galvanically-isolated REGEN powered by LPS-1, slimmed SD-card boot, etc.)--directly wired to my desktop (BJ/Belden CAT6a) for shared drive music access and headless control--sounds so good running HQ Player. I really think the only reason it presently beats my LPS-1-powered microRendu as NAA by just a hair is because I have not yet been able to get the mR/NAA to work with a direct to desktop connection (and I admit that I do not have an LPS on my Cisco switch or any LAN isolators).

 

But now that I see OS X's easy GUI controls for bridging, I may take another pass at this. Can anyone here confirm that they can get a Mac running HQ Player to play to a microRendu as NASS with a direct computer to mR cable? That's my only goal at the moment.

 

Thanks!

 

--Alex C.

 

P.S. My iMac on my desk has an Apple Thunderbolt>Ethernet adapter (with cable to my Cisco switch; DHCP addresses coming from the ADSL modem connected to the switch), and the 25ft. BlueJeans/Belden cable is plugged into the iMac's built-in Ethernet port (EN0) and runs straight to the DAC-connected 2012 i7 Mac mini (where I presently run HQP).

[Superdad]

I couldn't get wifi and ethernet to bridge in Mac OSX. In fact, after repeatedly failing, I did some reading and OSX expressly states this isn't possible. It might be possible in other OS's. Give it a try.

 

Hi romaz:

Any chance you or someone else here can write me a dummies guide to making this work in OSX using the Manage Virtual Interfaces GUI window of the Networks Prefs Panel?

 

My goal is to use my microRendu in NAA mode via a single Ethernet cable from my iMac (where both HQ Player Desktop and my music files reside).

 

On the iMac I have an Apple Thunderbolt>Ethernet dongle (EN1 I think) for connection of the computer to my Cisco switch. From the built-in Ethernet port (EN0), I always have a 25-ft. BJC/Belden Cat6a cable running to my tweaked Mac mini, and that is the cable I want to instead put into the microRendu.

I don't use wifi at all. It is turned off.

 

So I need to know both what settings (IP, etc.) to alter for the built-in network, and then what to set in the Manage Virtual Interfaces window as far as bridging. And then is there anything I need to change in the microRendu? (Of course I know to tell HQP to use NAA as Back-end once it is set up.)

To date with the microRendu, I've only been able to use it as NAA when running it through my switch, with my DSL modem/router providing DHCP service.

 

Many thanks to anyone that can walk me through this. I just don't have the time to do my own trial and error these days---and John is coming for a visit next week so I'd like to have this working so we do other fun things.

 

Best,

--Alex C.

[Superdad]

Sure, Alex.

 

System Preferences > Network > Manage Virtual Interfaces

 

Once in Manage Virtual Interfaces, click the "+" sign at the bottom left of the screen and select "New Bridge".

 

Give this new bridge whatever name you'd like. You should have a selection of interfaces listed for you in the box to include in this bridge. Specifically, you should see your native ethernet port called "Ethernet". You should also see listed your other ethernet port that belongs to your Thunderbolt device. In my instance, this is called "Broadcom NetXtreme Gigabit Ethernet Controller" although yours may be called something else. Regardless, check the two ethernet ports you want included in this bridge and click "Done."

 

This should take you back to the previous screen. In the left window pane, you should see this new bridge you've created and its status. If it states "Connected", you may already be good to go. Regardless, make sure this new bridge is highlighted. Then look at the right window pane to see the specifics of this bridge. In the Configure IPv4 line, feel free to keep the "Using DHCP" option. This works just fine for me although if you feel compelled to create a static IP, you can do so. If you decide to use the "Using DHCP" option, then you don't have to bother hitting the "Advanced" tab, just hit "Apply" if you're not already connected.

 

You should be good to go. On my Mac Mini, it was that simple although you may require a reboot.

 

To verify that your microRendu is online, open up Safari and type in "www.sonicorbiter.com" and the control screen should come up. From there, make sure the HQPlayer NAA option is selected and you should be ready to play music. Let me know if this doesn't work.

 

Perfect romaz! A million thanks! Works almost exactly as you said.

 

Just one note of caution to anyone else doing this on a Mac with an Apple Thunderbolt>Ethernet adapter (as the standard switch/DHCP router connection and the internal port--definitely better--as the one going to the NAA):

When you open Manage Virtual Interfaces, you will see that there is already one called "Thunderbolt Bridge" and its BSD name will be "bridge0". Do not delete this one! Just create a new one--I called it "NAA Bridge" and that will end up being "bridge1"--and as romaz said, edit it to have Thunderbolt Ethernet and Ethernet (the internal one) checked.

 

While I did not make the mistake of deleting "bridge0" (though wondered if I needed too), something did happen that others may or may not need to do:

1) SonicOrbiter.com found the directly connected microRendu (with an IP address auto assigned), but initially when clicking Manage (to actually logon to the mR's web control interface) it did not connect.

2) Thinking that maybe that "bridge0" was preventing it, I edited that (in Manage Virtual Interfaces) and unchecked Thunderbolt 1 and Thunderbolt 2.

That did it! The mR suddenly got assigned a different IP address and I was able to log on.

 

However, going back into "bridge0" (to check info to write this post), I see that Thunderbolt 1 and 2 are checked again; and then even SonicOrbiter.com could not find the microRendu. I opened then closed the edit window for "bridge0" (again, this is NOT the new "NAA Bridge" created--that's "bridge1") and then it refreshed and works fine.

So I think one has to keep a bit of an eye on it. Maybe it will stay stable, we'll see.

 

The other thing that is important before doing any of the above is to turn off Internet Sharing in the Sharing prefs panel. Otherwise it won't work. With my other usual set up--direct line to my tweaked, DAC-connected i7 mini--I often turned on Internet sharing between the Thunderbolt>Ethernet adapter connecting to the switch/web and the direct line. Only do that so if I can stream YouTube, Tiny Desk Concert, or other web audio to my DAC on rare occasion.

 

------

 

Anyway, the best part is that, as you promised, HQ Player/NAA--for the first time ever for me--works with a direct machine to machine (mR in this case) connection. I think this will sound fabulous (too busy this morning to actually listen).

 

Once again, it seems that OS X (okay, its officially called macOS these days) makes complex networking configuration easy for the lay person--once some very kind person explains it!

 

So many thanks to all!

 

--Alex C.

[Superdad]

romaz, we have been directly connecting devices for some time now. I have a how to guide for OS X where WiFi is used for internet and the Mac is used for playback directly connected to a microRendu. If you develop a similar guide for Windows (including how to undo it) that would be great. This "should" avoid having to use two ports on one motherboard which hardly anyone has.

 

Have you loaded at this thread:

http://www.computeraudiophile.com/f26-sonore-sponsored/sonicorbiter-direct-connection-mac-pc-beta-28606/

 

Right, except in that thread you explicitly state that direct connection does not work for microRendu as HQP NAA. As I reported yesterday, with the Manage Virtual Interfaces bridging technique, I got it to work with NAA.

 

But now I have a different problem--which I will either post in another thread or phone you about:

 

This morning I decided to update the OrbiterOS on my microRendu from 2.2 to 2.3. Now after updating, the mR is still seen, but in the App Switcher HQP NAA shows "Unknown" and grey instead of "Active" and green. No amount of restarting NAA, uninstalling/reinstalling NAA, rebooting or power cycling of mR will solve it.

 

And of course during this I switched back to a standard Ethernet switch/router connection (including deleting the virtual bridges, etc.). Again, the mR is seen and other modes can show "Active" and green. It is just that since upgrading OrbiterOS to 2.3 I can not get NAA to work at all. Very frustrating as my short listening last night with the direct connection (and mR powered by UltraCap LPS-1 of course) sounded fabulous!

 

Hope there is an easy answer to this.

 

Thanks,

 

--Alex C.

[Superdad]

Were you able to find a work around? Would be interested in knowing how things turned out.

 

I would like to try a similar setup with the mR in NAA mode directly connected to a Win10 PC running Roon Server and HQP.

 

Thx!

 

Sonore acknowledged that they had temporarily disabled NAA function in the update I had gotten that day. They fixed it the next day. Just update to the now most current version of OrbiterOS.

[Superdad]

OK I have some findings. Very interesting results! Thanks for pointing me in this direction.

 

I compared the following:

 

1. switch > FMCs > Aries Mini
   
2. switch > Aries Mini
   
3. bridge > Aries Mini
   
4. bridge > FMCs > Aries Mini
   

 

1 is my current configuration. My previous results were based on comparing 4 with 1.

 

Comparisons

1. 2 vs 1 (remove FMCs): yup, expected drop in SQ.
   
2. 3 vs 2 (switch to bridge, no FMCs): wow, big improvement!
   
3. 3 vs 1: this is a wash, to my ears. About the same. See conclusions below
   
4. 4 vs 3: (add FMCs between bridge and Aries Mini): minimal impact, if any.
   

Conclusions

 

In my setup, the bridged connection provides about the same improvement as putting FMCs between the switch and my Aries Mini. Refer to my diagrams in my previous post. The two FMCs are powered by Teralink X1/X2 (upstream FMC) and the Uptone LPS-1 (downstream FMC).

 

So on the one hand, by going bridged, I can eliminate the FMCs, and repurpose my LPS-1 for something else. But on the other hand, I abhor the presence of the PC in my listening room. And - I still have some lingering network issues with the bridge. In addition to the SMB woes I mentioned in my previous post, I also found today that my control point (lightning DS app on my iPhone) would lose contact with the Aries Mini in the bridged configuration. I know this relies on UPnP and multicast support in all routers and switches, so it's possible the bridge messes with that.

 

The right answer for me, at this point, is to close the chapter on bridging and go back to my switched environment. At least I won't be wondering if I was missing out on some unclaimed SQ improvements.

 

I may revisit this if/when I decide to get an SMS-200, and/or try Roon.

 

Maybe I should fly you out to my place in Yosemite so you can do all the experiments on MY system that I never have time to!

[Superdad]

No one can fault you for your effort, that's for sure. I have been getting the sense for some time now that this "direct" connection tweak benefits mainly the mR and sMS-200, with or without HQP. This finding adds further to the mystique of what is actually happening with this direct connection. A real head scratcher...

 

I wouldn't say that at all. I've been doing direct Mac to Mac connection for 3 years years now--primarily to get shared music files on my drives to sound as good as from local SD card (see: http://www.computeraudiophile.com/f27-uptone-audio-sponsored/uh-oh-i-beat-my-sd-card-trick%3B-bypass-your-ethernet-switch-and-make-your-external-drives-sound-close-ram-disk-using-apple-thunderbolt-ethernet-adaptor-and-second-network-connection-18475/)

 

 

Sent from my iPad using Computer Audiophile

[Superdad]

I have set this up. Works fine.

 

Couple of questions if you don't mind:

 

1- I have attached to microRendu to the Thunderbolt adapter and my switch to the Ethernet port - have you tried to swap this and whether that's any different?

.

 

Hi Miguel:

 

I can tell you beyond any doubt that the built in Ethernet port of the Mac sounds far better than the Thunderbolt>Ethernet dongle. I did that comparison with my Mac>Mac direct connection 3 years ago. (See: http://www.computeraudiophile.com/f27-uptone-audio-sponsored/uh-oh-i-beat-my-sd-card-trick%3B-bypass-your-ethernet-switch-and-make-your-external-drives-sound-close-ram-disk-using-apple-thunderbolt-ethernet-adaptor-and-second-network-connection-18475/)

 

Use the Thunderbolt adapter for the connection to you switch.

 

 

Sent from my iPhone using Computer Audiophile

[Superdad]

I suspect the benefits we hear are due to the elimination of unnecessary and redundant hardware of the switch, and it's power supply. A switch is just another computer with multiple NICs a processor, RAM and software. It makes sense that reducing the number of devices touching the music signal leads to improved SQ.

 

This does not mean there may not be specialized switch's optimized for music that will sound great.

 

You are correct Larry. In particular, it is the dirt-cheap Ethernet PHY chips used in most switches--which often produce marginal signal integrity (thereby causing the receiving endpoints to work harder and thus generate more bursty PS draws and ground-plane noise; same as the issue with USB and the aim of the REGEN and similar devices). The PHYs are better in some of the high-end managed switches (Cisco, etc.), but there they use their own custom, massively integrated chips which each handle a bunch of ports--so it is hard to know if that helps our cause. And of course power supplies, regulators, and clocks in the switches can all be improved.

 

By the way, the Broadcom Ethernet controller chips used in better computers (and in all the Macs) are some of the best available (John knows these from the inside). So going direct does have some basis in principle for why it is better.

 

 

You mentioned a specialized Ethernet switch optimized for audio:

During his stay with me a few weeks ago, John and I selected ideal Ethernet switch chips (they have varying interfaces) and Ethernet PHYs (once that don't have a bunch of analog blocks which are to turn things on and off to save energy), plus his favorite isolator chips to go between the switch chip and the special PHY. It would of course have a great clock, ultra-low noise regulators, and an SFP cage for optical. And for power there would be 2 DC input jacks (optional use, they would be the kind with a third contact switch), so someone could separately power the "clean" side isolated output (with an LPS-1 of course).

 

The above is a broad outline for a truly "audiophile Ethernet switch." Actual engineering of it involves a bunch of other unmentioned complexities (which John explained to me and which mostly went over my head).

But before everyone gets all excited by the prospect of such a product from UpTone, know that we discussed it in relation to another significant Ethernet-related isolation project we have slated for the fall (after his move), and decided that the market for the above-described switch product is much smaller than for the other secret product. So don't expect such from us this year!

 

--Alex C.

[Superdad]

But this was not my best overall SQ, however. I went back to El Capitan on the SD card yesterday and without question, right now, this is where the magic is at. That relaxed, natural and effortless presentation that made the Mac Mini so magical when I first heard it was back and gone is the HF noise that even my hard drive seemed to still have some of. Where OSX lacks in precision and imaging compared against my optimized Windows setup, SOtM's better clocks seem to more than make up for it, especially now that I am able to reintroduce my switch back into my chain without irritation. While I still believe optimized Windows is better than Mac OS, the secret is to be able to run the OS off a flash card of some sort.

 

Great post Roy.

 

Of course your above paragraph is a bit of deja vu from 3 years ago :

http://www.computeraudiophile.com/f27-uptone-audio-sponsored/attention-current-mac-mini-users-boot-mavericks-sd-card-load-ramdisk-dismount-your-internal-sata-drives-and-pour-drink-musicians-walking-out-your-speakers-18159/

 

While my optimized SD card is still running Mavericks (with about 65 processes/280 threads), I'm trying to make time to slim an El Capitan install--to at least get under 100 processes--so I can run the current version of HQ Player (via other than the microRendu/NAA). Staying away from the truly bloated Sierra!

 

It is quite something how sonically competitive a simply-tweaked Mac mini can be. My setup with it is:

2012 i7 2.6GHz with 16GB RAM

Our Mac mini DC-conversion/Linear Fan Controller Kit (MMK)

Our JS-2 choke-filtered, dual-output, 5-7 amp LPS

32GB SD card booting heavily-slimmed OS

Internal SATA HD dismounted (I'd remove it entirely, but really need it, with its multiple partitions, for experiments and OS image building; but I "eject" all partitions when using for playback)

 

Only connections to the computer are:

1) the DC power cable (and the coax/SMA for the MMK>JS-2 pseudo-Kelvin-sense voltage feedback circuit);

2) the USB cable (ports 1 and 3 are the best sounding by far) feeding my pre-production ISO REGEN (itself powered by an LPS-1 of course)

3) 25 foot BlueJeans/Belden Cat6a Ethernet cable direct to the 27" 4GHz iMac on my desk--used for Screen Sharing and sharing of a large drive with my music library.

 

I have the direct Ethernet connection set up for Jumbo Frames (MTU 9000) as that reduces overhead and I thought I heard a difference long ago.

 

--------

 

I might build up a high-power machine for DSD512 someday (Larry bugs me about it all the time ), but life is too short for me stress with Windows. Seems likely that Linux DSD issues will get worked out, and I do think that a split high-horsepower SRC/SDM machine to low power, all linear regulated renderer device will be the most desirable.

 

--------

 

Continue on gents. I watch with pleasure...

 

--Alex C.

[Superdad]

CD as transport is relatively simple:

Rotate the disc in constant speed, read it through the laser head, and then output to the DAC. No error correction (real time).

 

That is incorrect. Real-time CD playback does have the disc rotating at a constant speed, and there is error correction--but it is based on interpolation.

 

You may want read up on Reed-Solomon encoding and eight-to-fourteen modulation.

 

In fact the single largest factor in "computer audio" (where CDs are ripped, stored, and played back) being superior to conventional CD transports is the utilization of CD ROM drive data mode extraction--instead of realtime, variable-speed, Reed-Solomon error correction, etc.

 

 

Sent from my iPad using Computer Audiophile

[Superdad]

Alex,

 

I think you mixed up speed and rate here. Audio CD playback reads the data off the discs at a constant rate, but the rotation speed varies from 480rpm - 210rpm due to the circular track length varying from inner to outer circumferences.

 

Hi Greg: I mixed it up only in writing, not in my mind. I entirely meant to say "Real-time CD playback does NOT have the disc rotating at a constant speed, and there is error correction--but it is based on interpolation." I blew the very correction I was trying to make to greenleo! Oh well, it was a long day...

[Superdad]

I've been using a display emulator with my Mac Mini just to allow quicker screen sharing connections. Apparently it does this by turning on the GPU. I kinda wondered it this would be detrimental to SQ. I'll pull it and see.

 

This is the device by the way:

https://www.amazon.com/dp/B00FLZXGJ6/ref=cm_sw_r_cp_tai_arnWybJ3D0SKZ

[/url]

 

I do not agree (at least for Mac mini) that it is a foregone conclusion that eliminating the monitor (or monitor EDID emulator dongle) will sound better. Without an attached monitor or EDID dongle, the CPU performs the GUI tasks. With a monitor or dongle, those tasks get put off to the GPU.

 

So in some cases it might sound better to keep the GPU active and the load off the CPU. I have not made that comparison in a very long time. My system is much more sensitive/revealing these days, so maybe I'll try it again.

[Superdad]

My 2014 Mac Mini that runs off an SD card utilizes a 15w CPU and only 4GB of RAM with no internal hard drive and with the wifi card removed. At idle, it consumes less than 5w and never runs warm even when active. Because the fan never has to ramp up, I never hear it. Of course, when it boots, it will require more current but I suspect a 12V/3A PSU could easily power mine.

 

Sorry Roy, but a 3A PS will not boot a Mac mini, no matter how slim you make it. I've done the tests on the bench, and minis will fail to boot with anything less than about 3.9A.

Just FYI.

[Superdad]

To go from 4GB of DDR3 (which is what I currently use and what I expect to use with my new build) to 16GB of DDR3, if this calculator is to be believed, under load with 16G of RAM, you would draw a whopping 4A more current compared against 4G of RAM. DDR4 fares a bit better and the draw is 3.3A more when you jump from 4G to 16G but this is still huge. As for 1 vs 2 sticks of RAM, using 2 sticks of 8G RAM draws no more current when compared against just a single stick of 16G RAM.

 

Whoa! 4 amps for 16GB of RAM?! That calculator you are using is not to be believed... If anywhere near that much current was drawn by RAM (maybe magnetic core memory from the 1950s?) we would not have laptop computers and the traces on RAM modules would just burn up...

 

Just sayin'...

[Superdad]

2 hours ago, romaz said:

This is correct.  Paul has been very adamant that IDE > SATA2 > SATA3 with regards to SQ based on electrical noise.

Funny, if you go to my 2013 report on drive interfaces--and do a search in it on PATA--you will see me remarking how the old IDE>Firewire400 drive interface I had was the best sounding of all (well third, behind SD card and the gold standard of RAMdisk).

 

[Superdad]

10 hours ago, greenleo said:

HQPlayer Win Server 2016 GUI Network Bridge Walk Through

 

It took me some time to figure out how to do the direct connection in this OS.  I hope that this walk through may be beneficial to the members who is/will use ...

...snip, snip...

 

Enjoy

 

Wow Greenleo, you deserve a lot of credit for putting that all together!  I assume that some of it is applicable to regular Windows users too?

 

Seeing what you guys have to go through to make this work under Windows sure makes me appreciate OS X--where a few clicks and it just works.  

[Superdad]

4 hours ago, tboooe said:

Fascinating idea about using an HDD instead of SSD.  I have an old 2.5" HDD laying around that I will put into my NAA PC to see if makes any difference.  I wonder if the noise from the SSD is why people (me included) hear improvements when changing SATA cables???

 

My various testing experiments over the years pointed to the SATA  interface itself as being less than ideal for various reasons. 

 

Too bad that low power IDE/ATA drives got supplanted by SATA before capacities made it up to 1TB. I think the largest were 500GB--and those were multi-platter 3.5" units. 

 

And do IDE cards even exist for modern PCI slots? 

[Superdad]

14 minutes ago, greenleo said:

Alex,

 

Do you still regard playing music files from RAM disk sound best?

 

It is a pain in the neck, and sometimes it can almost be too revealing, but yes, for me it is the gold standard.  Often (well nothing is often for me these busy days) I'll use it as a comparative reference to judge other file playback locations/interfaces/etc.

There is just something about the unity of the wavefront launch (sorry, I'm bad at describing what I hear, and that term is the best I've come up with) when the track is played back from a RAM disk.

I recall the benefit was greater with Audirvana than with HQ Player.

 

--Alex C.

 

P.S.  I sure wish the phone company would hurry up and fix the big service box that was flooded in last night's storm.  We have been without landline phone service and internet for 24 hours.  I am really tired of typing on my cell phone (though at least now I paired a keyboard with it).

[Superdad]

13 hours ago, lmitche said:

Once in the resource monitor watch the disk activity tab.

 

Bring a barf bag.

 

LOL!  Every time I look at Windows I feel that way. 

 

32 minutes ago, lmitche said:

The manufacturers don't know anymore then we do.

 

Especially since we don't have the time to dig into the fringe weeds the way you guys do!  But we watch and come up with new product ideas to hopefully address/cure some of the ills.

Or maybe take it all in an entirely new direction...   (Can't wait until John's move is done and his lab is back up.)

[Superdad]

On 3/31/2017 at 10:41 AM, amgradmd said:

Connect a Thunderbolt Ethernet adaoter into one of the TB ports and direct connect the ethernet cable to the DS DAC. 

 

@amgradmd If you did as you described, then you now in for a real treat:

 

The signal integrity of the Ethernet controller in Apple's Thunderbolt>Ethernet dongle is no where near as good as the Broadcom controller chip in your Mac mini.  

So reverse your set-up, and make the direct connection to your PSA DAC;s Bridge II from the Mac mini's built-in Ethernet port--and use the TB>Ethernet adapter for your regular network connection.

 

Try that and I promise you will be delighted.  As mentioned earlier in this thread, I started doing my Mac>Mac connection this way years ago.  For me the difference between the dongle and the built in port is not subtle.

 

And maybe get yourself a BlueJeans/Belden Cat6a cable.  I compared a whole variety of Ethernet cables (sans any of the audiophile brands), and the BJC was the clear winner--and for such a modest price.

 

Cheers,

--Alex C.

[Superdad]

On 4/11/2017 at 4:08 PM, ElviaCaprice said:

 

It's not perfect, no galvanic isolation is perfect, but I have to say, Chords galvanic isolation on it's DAC's is probably the best I've seen (or heard about from others) in the market.  It's that good.  In fact, it has me doubting the benefits of the upcoming ISO Regen, in conjunction with the 2Qute.  I'm getting the best sound I've heard yet with my current setup and that doesn't include any reclockers or additional galvanic isolators.  I think the Topaz (and improved 2Qute power supply) has really brought it together for low impedance throughout my system and even made my poor HDPlex a better power supply.  Instead of adding new expensive reclockers/isolators, I would rather now turn to the server itself and see what kind of additional improvements can be had, whether it's a new power supply, mobo, or clocking.

 

What you say is puzzling in that if you can hear differences at the computer end  it means:

a) such changes are modifying the signal integrity (eye-pattern variables of amplitude, slew, noise, jitter) and leakage current of what is sent to your DAC--as those are the only mechanisms by which bit perfect data can affect the DAC;

b) your DAC is therefore not immune to such vagaries;

so

c) best signal integrity (via regeneration and galvanic isolation) right at your DAC is going to be desired and required in any case.

[Superdad]

On 4/12/2017 at 5:49 PM, Johnseye said:

 

Assuming I went with the HDPLEX 160W DC-ATX would I need Paul to make one of the rails of the SR7 a 19v?  If I go with the Pico it stays 12v but the sound quality could suffer?  Is 12v enough to power a miniATX, or does it depend on the total watts used, or what's being powered by the different voltages?

 

Just to be a bit more clear about both the picoPSU and the HDPlex cards:

They are both switching regulator adapters.  That is, they use DC-DC switching converters to drop the one input voltage to 5V and 3.3V.  

Unlike the picoPSU (XT150 and XT160 versions) which run from 12V and just pass that--ideally LPS  sourced--12V to the motherboard, the 19V input HDPlex boards have to use fairly large switching converters to drop down to for the high-current 12V feed.

 

So regardless of whose power supply you choose, for "ATX" application I'd recommend you go with the 12V input picoPSU to best preserve the "goodness" of your LPS for the critical main 12V powering of your motherboard.  And if you have another supply or an LPS with an extra rail, then you can consider directly powering some important 5V things such as you OS and/or music drives.

[Superdad]

15 minutes ago, Silly goose said:

With Ravenna, no changes upstream of the Fiber PHY has any impact on the sound. Unless of course it's from DSP. The days of PC and digital signal path hardware tweaks will be long forgotten in the near future. 

 

But for small DAC's like Chord, the FPGA based solution might be a bit too big still. They will likely need to wait for the ASIC in the works. Set for release mid 2018, early 2019, it will finally commoditize  AES67 for the DAC's and active speakers at all price points.  

 

Ha ha.  The "Ravenna revolution" has been just a few months away for almost 5 years now.  

I'm not saying it (or something like it) won't ever happen, but:

a) the hardware is not the only obstacle to adoption, and

b) as those here who are using the Dante/Focusrite/Rednet boxes have discovered, it is not 100% immune to all factors (i.e. those guys are "tweaking" too).

 

So wake us when the "revolution" starts and you have some actual board and software solutions to point to. 

[Superdad]

2 minutes ago, romaz said:

 

This is a bit of a presumptuous.......

I don't know what the future holds.  Digital is evolving very rapidly and it's unlikely what I have today will be with me in a year or two based on my history.  If it turns out Ravenna wins out, I'll gladly jump onto that bandwagon but not because all sources sound the same, but because Ravenna sounds better.  Of course, this is also contingent on my preferred DAC having an Ethernet input.

 

Geez Roy, how the heck did you write and type that so fast?!  Great points though, and you did not even get into the issue of virtual sound card software, licensing, and if that stuff is really going to be transparent.

 

[But of course you have seen Silly Goose honking about Ravenna religion in a half dozen threads each day this week.]