Best Source for DirectStream/PWD

There has been a lot of discussion lately regarding the best source for the DS/PWD.

For example, I was recently listening to music via my computer (Macbook Pro, Audirvana, USB, PWD) and couldn’t get into the groove (the music sounded dry and un-involving). I then started listening via the PWT and I was tapping my feet within seconds. The music sounded more natural and liquid to me. I know Paul has posted how great his MacMini source is, but I still haven’t gotten my computer to sound as good as the PWT. In addition, Al Rainbow has posted that using a CAP (I’m not familiar with a CAP or how to set one up) has made a big improvement in sound.

In general, it seems like the source is a cause of variability and we would all like to learn how to get the best sound possible via optimizing the source.

Lets start a dialogue to learn and capture observations from different users regarding how source–>DS/PWD can impact the sound and why.



The Computer Audiophile Pocket Servers (C.A.P.S.): Clicky

If you are not a DIY type, they can be purchased pre-assembled from Small Green Computer.

DAVE1210, I think one of the first things that needs to be considered is what arrangement you would like to live with. In my case I have a fairly robust PC feeding the DLNA compliant devices throughout my house via hard wired Ethernet. For me, I’m not sure I’d ever consider yet another computer of any type in my listening room if it isn’t needed. Fortunately the DS with Bridge sounds at least as good, if not better, than the PWT being fed by I2S (and I agree that sounds pretty darn good). I have a NAS, also located in my media source location (my home officewink) but localized through it’s own set of network switches so that it is physically separated from the main router and switch that my PC does everything else on. So for me I’m not sure going USB would give me any advantage.

When the Bridge was introduced, there were a number of users who pronounced it to sounds as good as the PWT. And promptly sold their PWTs.

I recall some indicating they subsequently wished they had not done so (for reasons of sound, gapless, etc.), but the majority remained comfortable with their decision.

I am intrigued by the reports that some highly specialized servers, such as the Bryston BDP-1/BDP-2 sound appreciably better than other computer based solutions, such as a Mac.

I had used the bridge with each version of the DAC (I, II and DS) since it was first available. Recently after being frustrated with the lack of gapless play and occasional drops, I moved to the Senore Rendu using I2S input to the DS and J River 19. The sound quality became noticeably improved compared to the bridge, and allowed gapless play and no more drops. I considered the Bryston, but the Rendu appeared to be a more straightforward solution for me.

I don’t think one type of source is necessarily better than the other. But whichever you use, it’s worthwhile to take the time to optimize it since the DS is certainly sensitive to what’s fed into it. I’ve been very happy with my Bridge, fed from my NAS; using an Apple Airport Extreme in place of a cheap switch did make a difference.

Lately I’ve been experimenting with USB playback with foobar. Even using a dedicated PC for audio (CAPS Carbon), I got better results with the Bridge. Today I tried Fidelizer on the PC, which definitely made for more details, a more subtle overall presentation, and more realistic-sounding instruments. I think the Bridge is still a little better–but the power brick that supplies the PC could probably use an upgrade and I’m waiting on a USB cable I’ve ordered. Truth is, now I could live with either one.

I do think that computer/USB playback introduces more variables, especially if the computer is used for tasks in addition to audio playback. There’s the hardware (amount of memory, quality of USB ports, potentially noisy disk drives), the OS, the player software, how many background processes are running, etc. That’s a lot that all has to come together well for best SQ. I also think that computers, especially those with high-powered CPUs, are likely to introduce more electrical noise to the system than a low-powered NAS. For network streaming, the quality of the renderer is very important (see badgerbob’s comment about moving from the Bridge to the Rendu). But once you’ve got a good renderer and at least cat5e cable, with maybe an upgraded router/switch, that’s pretty much it.

And, finally, Tony is absolutely right about living considerations. Some people can’t install a wired network because of the design of their house. Others, like me, don’t like using a laptop for playing music. I didn’t even consider USB playback until after I bought the Carbon to rip vinyl with. I run it headless so I can still use my iPad to control it and don’t have to wrestle with a laptop.

magister said using an Apple Airport Extreme in place of a cheap switch did make a difference.
I would like to improve my switch too, I have an Extreme as my router located 100 ft away upstairs and an Express in media room as bridge plus an 8 port switch, so could I switch the wiring and connect the Express to the Extreme, and the switch to the other Express port ? Assuming the Express too would improve the SQ. Trying to understand the wiring.

Excellent points everyone. Thanks for taking the time to comment and keep the dialogue going.

As Magister said, there are so many elements in a computer setup that can impact SQ. Makes me think that “MacBook Pro w/Audirvana” is not the most detailed way to describe my computer source.

I remember when I was evaluating audio software programs for the Mac and I couldn’t believe I was hearing significant differences between the different products (it’s just bits, right?). It probably should have occurred to me at that moment that computer audio might not be as straightforward as I thought. In hindsight, maybe it should be obvious that computers would take a bit more work by the end user to get great sound. After all, the average computer isn’t designed to just play back audio at the level we might expect from a high end product.

That said, I have never considered trying to optimize the PWT for better sound. I accept that the ‘optimization’ work was done in the design and engineering phase. Less DIY, sure. More convenient, yup. But I don’t think I will stop fiddling and tweaking the computer to get it sounding great, and I am glad I have the PWT to compare to.

Side note: Some of this reminds me of the time when Andriod devices were starting to make headway into the smartphone market and there was a segment of the iPhone market that was switching because the Android phones were more highly customizable.

And…if it wasn’t for this community I wouldn’t know about CAPS. Helping music lovers get the best sound possible from computers via standardizing/identifying technologies and reasons for why the components/technologies are better should help us get to a better place.



So, I’m posting this here rather than starting my own thread - since this is kinda what we’re talking about already.

I got my industrial linear PSU yesterday - dialed it in, then powered my little Lenovo Mini-PC from hit.

Crap what a difference! Not all of it good though. I gave it a listen for about an hour and I still can’t fully describe all the changes. I swapped back to the stock PSU (basically a 19v laptop power brick) and the system went “back to normal” - which after this linear PSU change I think I need to reevaluate.

I’m super busy at work, so I’ll write more later. I’m honestly having trouble wrapping my head around all the changes I’m hearing. I don’t see how changing out the PSU to a linear one could change the sound so drastically…

Linear supplies aren’t better than switching supplies in all ways. Some of my best equipment has switching power supplies (my EMM gear.)

Switching supplies can provide extra current at most points in each 60Hz cycle of the power. Linear supplies charge caps (often big caps) during smaller portions of the cycle of power and then it’s up to those caps to provide current for the rest of that cycle. Obviously a lot depends on the quality and make up of said caps. But caps don’t perform the same for all frequencies (nor do switching power supplies…)

Then there are issues of how much of the incoming mains EMI the power supply filters (or let’s back into the AC network from a given device.) A linear supply in general adds much less hash to the power than a switching power supply, but it also is often a much less effective filter for hash going thru it. If a switching power supply is filtered enough to get rid of the generated hash it might well filter incoming hash much better too.

Like everything in this (and most) hobbies, you can’t always predict ahead of time what the net effect of a given change is.

Thanks for that info, Ted. I’ll cut and paste what I wrote in another forum - maybe you can help me suss it out then. Most things sound better, but on the high end I’m getting a bit of an edgyness or etching that reminds me of the sound my Oppo has vs the DS.

Here is what I posted at

Well crap - this Linear PSU…um, well…the whole damn system sounds different. Like so very different I have to really sit down and reevaluate the system to figure it all out. It’s not subtle at all.

Right off the bat it has an apparent loudness difference.
I’m hearing every instrument and voice louder - almost like everything been compressed or “normalized”.
Bass sounds huge, and honestly overpowering.
It’s also feeling a bit edgy, not at all in a good way.

I’m going to bust out the tape measure and make sure the dogs didn’t bump the speakers (to account for such a huge difference in bass), and switch back to the stock mini-PC power supply. This is weird how much this sounds different - so as I said, I need to reevaluate and make sure there aren’t other factors in here.

So a brief update - After initially being bowled over by such a grand change, I did go back and measure out my speakers and realign them with a laser (yes, I’m totally serious). One speaker did get bumped considerably, but I don’t think it’s enough to justify the change in bass. Getting the speakers back in line actually helped tighten up the bass a bit, but it was still huge.

So next step was to listen for a track or two…which turned into about a dozen tracks. The sound was so interesting and different I just kept rolling tracks, completely forgetting to A/B the power supplies. When I finally remembered what I was doing, I picked Deft Punk’s Doin’ It Right which is bass heavy, dynamic, has some neat reverb FX, and is already a little edgy on the high end. Basically all the things that I noticed an immediate change with the big industrial linear PSU.

So I switched back to the stock 19v 3.34A “brick” PSU (this mini-PC is basically the guts of a laptop in a metal box, with no screen, so this PSU is a laptop brick) - and suddenly the sound went a bit flat. The bass didn’t punch as hard or feel like it was as tight. The reverb ambiance was much shorter. It was still as clear and detailed as the DS is expected to be, but it lost a little focus. The stock PSU also reduced the edgy etching of the high end…in fact, at one point with the Linear PSU, one track I put on sounded exactly like that etched high end that my Oppo has, but with the added DS detail.

As I’ve said before, I’m a big skeptic and everything needs to prove itself in my system. Most cable/power/IC changes to me are very slight changes, and not always improvements. I’m pretty skeptical that a linear PSU would make such a difference since the computer is just passing “bit-perfect” bits down the pipe. As long as those bits get to their destination unmolested, it’s the DAC that makes the difference. That’s how it looks on paper and how the “math guys” say the world runs. But I’ll be damned if this isn’t a big difference to me - like big enough that I could say 4-5% difference which is huge for just swapping out a PSU.

I’m going to have to talk to some guys smarter than me to help me wrap my head around this. I understand the concept I guess, the PSU doesn’t inject noise, or if it does it does it in a different way (which would explain the high end edginess I’m hearing). If there is less noise then I guess that would make blacker backgrounds which would make the voices and instruments seem louder (just thinking out loud now), allow me to hear the reverb even better than what the DirectStream does on it’s own (which is an amazing accomplishment). But I feel like there is something else going on there that I’m not grasping.

Ok, enough rambling - we have a listening session going on tonight - we’ll see what the other listeners think. I’ll probably also ping Ted at the PSA forums and see if he can help me wrap my head around this.

Any further thoughts on this and how it relates to the Linear PSU? I’m definitely going to explore further and give it some time to settle. By the end of the night it was all sounding pretty good, but that high end etching that I normally associate with hash bothers me. I doubt it was always there (and hidden by the stock PSU) considering how smooth the DS is, so it’s something added with the Linear

I wouldn’t try to come to any conclusions about your new PS and its effect on your system without giving it some break-in. Every component I’ve ever used has changed over time, to a greater or lesser extent, including power supplies.

First off I don’t know any details about the linear supply you used. In contexts like this the word “industrial” usually means robust and cost effective but perhaps brute force and unrefined. I.e. I suspect it’s letting a lot of hash thru or even contributing some of it’s own. Rectification diodes can generate a lot of high frequency noise on each switch on and getting fast recovery (or better soft recovery) diodes costs more money for no particular return in an industrial environment. Also industrial power supplies are usually used in an environment with lots of high frequency crap around, nobody really cares, so an industrial supply isn’t likely to even try to address any kind of filtering.

High frequency hash often gives an edge to the highs like I think you are describing. That hash could be coming from the power supply thru the PC to the DAC or perhaps, for example, from the PC thru the power supply and back into your AC power system.

On a more speculative basis getting very good DC performance out of the supply (which an industrial linear supply should do well) can really firm up the bass and give that louder presentation you mention.

Thanks Ted! You’re educated guess matches up with my uneducated speculations. I’m wondering if I swap out the diodes on this PSU, if I can clean up some of that hash and make an industrial PSU closer to an expensive “audiophile” PSU. They look pretty easy to get to, and it’s a low cost improvement I could try.

Thanks again for your thoughts and ideas!

I have a Bryston BDP-2 on the way and expect it in a couple of weeks. I look forward to hearing whether it sounds different/better than other computer based sources as is often reported. It will also be interesting to compare it to the PWT. The Bryston works as a NAS; plug in USB and or eSATA drives and stream away.

In preparation, I bought a WD 1GB portable USB HD. This little guy is astoundingly neat. Small, quiet, fast, powered off of the USB port - what an elegant bit of technology. And cheap. My other external drives are a couple of years old, externally powered, comparatively noisy and huge. Cool stuff.

That’s the same drive I used on my Oppo before I went with a Synology NAS (I really needed redundant drives and backups for my laptops and music archive).

IMHO, at least on the Oppo, I could absolutely hear the difference between music played off the original CD, a big desktop hard drive with external power supply, and that little WD Passport drive. The guys over in the AVS forum said I was deluding myself, show me the measurements, etc- till I E-mailed Oppo and asked, and they agreed with me 100% that a drive powered off the Oppo probably sounds better because of less jitter and no external power to pollute the chain. Then everyone shut up.

I hate getting draw into those “show me the specs” debates.

Anywho, it’s a great drive and I highly recommend them (if you need an external USB drive)

Yep, I have my music library on two 2T WD My Passport USB 3.0 portable drives. I also back it up to two other alternating sets of them. The drives are so cheap at Costco that I’m thinking of adding three more for my library to grow to 6T even tho at some point some sort of little RAID box, NAS, or whatever starts making more sense. It’s just so handy to haul my library around on those small discs. So far the reliability has been better than most of the desktop drives I’ve had in the past.


And here I bought it merely because it looked like a really neat option. I did not even consider it might sound better. Or that it was particularly robust. Mine is now loaded with 20GB of music files for initial testing purposes when my Bryston unit arrives.

I love that Oppo supported LR’s experience. Very satisfying and great to learn they are truly listening to their product.

Bryston’s support people prefer the sound of USB flashdrives plugged into one of the USB ports, and even go so far to state a preference for Crucial flashdrives. Their BDP-2 is provisioned to accept an internal SSD, but explain this is offered only because of consumer demand for internal storage. I plan to buy an SSD to compare its sound with a flashdrive and an external drive to find if I hear a difference.

Another little thing I like with the Bryston is their S/PDIF out is BNC to best match the characteristic impedance of the cable and subsequent input, nicely pro audio. Of course, Bryston has lots of experience with both the pro and enthusiast aspects of the market.

Unfortunately, the Bryston and DS do not play together via the Bryston’s USB out.

Since no one has mentioned the Auralic Aries as a source for the DS, it is now done.

Absolutely no regrets so far. I have now abandoned any thoughts of getting a computer. I use a NAS.

The only time I need a computer is for any metadata tagging and hirez download.


Have you recieved your Aries’?

It certainly looks appealing. Is it as pretty to look at as the pictures?

Does USB to the DS work?

(I edited your post to substitute the weird automatic link for the word “Auralic” to PS Audio’s page on the P10, to instead point to (English) for those interested in learning more.)