Article: The Value Proposition In Computer Audio: Nuts, Bolts, and Building Blocks - Building a Home for Your Player Software Part 2

[bluesman]

View full article

[bluesman]

1 hour ago, davide256 said:

Thanks! Haven't played with an RPI4 yet, did you find the USB out improved vs the RPI3b+?  Played around with a variety of these devices about 18 months

ago but could never get USB out from the RPI3b+ to be as clean as a microRendu.

If you used the stock Pi SMPS and powered your DAC through USB with any other USB peripheral connected, you weren’t getting all the 3B+ can give.

 

On basic program material (eg 2ch DSD or lighter, little or no DSP) that doesn’t overstress the 3, I don’t hear a difference between 3B+ and either USB bus on the 4 through DACs that are getting enough of their own clean power.  But when feeding DSD files from a USB HDD without its own PS while playing them back through a USB DAC using USB power, I think the 3‘s grainy and suspect it’s from borderline low voltage plus slight data flow interruptions.
 

To Chris’s point, I’ve never owned a microRendu and have only heard them a few times in other people’s systems. From memory, I think SQ from Roon Bridge on a 4 gig Pi feeding files of any size and complexity from NAS by gigabit Ethernet into an externally powered DAC via USB3 with no other USB peripherals connected is mighty close (if not equal) to what I remember of the mR.  I don’t recall and can’t find the CPU core count, the Ethernet spec or the various internal bus and R/W speeds for a mR, any of which may have contributed partly to this. Also, many mR buyers went for seriously over-the-top PSs because it was sold without one.  
 

 

[bluesman]

1 hour ago, Mortsnets said:

I've read that the RPi4 USB has solved drop out problems, but sound quality on mine is not nearly as good as using my Allo DigiOne.

I assume you compared them into the same DAC and audio system powered by the same PS, which would be the only way I know of to compare them directly.  And I assume you’re comparing USB3 from the Pi to SPDIF from the Allo.  If the DAC had its own power for both, the only variable other than the Pi’s USB is the DAC’s USB processor(s) - and the DAC side of the USB pairing is most often ignored in these optical-vs-USB comparisons.

 

If you prefer SPDIF to USB, as many do, that’s fine and what you should use.  I’m still on the fence because I haven’t heard any truly direct comparisons myself except my Emotiva Stealth and my SMSL SU-8, both of which have optical, coax (on the Stealth), and USB inputs. The Emotiva has an older style C-media USB chip that’s simply not as good as its other digital inputs, and the difference is audible.  But the SMSL (v2) has much better USB circuitry that sounds little if any different to me from optical - I doubt that I could identify one from the other blinded.

 

Stay safe and enjoy the music!

[bluesman]

34 minutes ago, davide256 said:

Was using the LPS 1.2 for 5V PS in my experimentation. Oddly enough the reason I stopped using a microRendu was that it didn't scale up with improved

power supply whereas a Pentium NUC did. The criticism of RPI before the RPI4 was Ethernet and USB shared the same bus, guess its high time to go back

and dabble again since the RPI4 doesn't do that. My wife has just been asking if I could setup a music source in the living room...

Very interesting!  The microRendu was sold without PS, and they offered 9 recommended options (from a $50 iPower to 4 figure monsters) with glowing descriptions of the sonic improvements to be had. I find these and similar quotes about power supplies for the mR and many other devices to be more than a little amusing (bold italics added by me):

• From the 2018 TAS review: "If it seems goofy that a power supply should cost nearly twice the price of the player, remember that the power supply contains much heavier components, is housed in a larger, fancier case, and is usually the primary factor in how a component sounds."
• From the PositiveFeedback review: "[The Channel Island Audio PS is] for those who are looking for a serious step up in sound quality, without totally bankrupting themselves...the VDC7 Mk. II offers a tremendous improvement in the overall presentation."

The PI 4 performs wonderfully for me - I now have one driving my living room system and one in my recording "studio".  I just sent Chris my next article, which is about easy mods to the Pi (none destructive and all well within the ability of anyone who can get a new one to play music).  It's amazing how you can improve them with a little cooling, an inexpensive externally powered USB SSD, a better microSD card than the one recommended and sold by the Pi Foundation, and a few simple command line entries.

[bluesman]

57 minutes ago, davide256 said:

It's tempting to try the Signature Digione , better clocks and circuit board.

I'm always happy to try anything.  But since I retired, I've stopped paying for the privilege unless I want or need the item anyway, or I'm getting it at a price that will let me resell it without taking a bath.  Now that we're in an apartment, the shelves are so full that I'm even contemplating selling some of my old favorites because they're not getting used much.

 

As for the Signature DigiOne, I'd suggest reading the very revealing thread following the ASR review [sorry - I can't get the link to be hot: https://www.audio “science” review/forum/index.php?threads/review-measurements-of-allo-digione-signature-and-diyinhk-pro3z.4660/] before putting out the money for both the device and the 2 power supplies it needs. The wide diversity of opinion suggests to me that it's not a slam dunk improvement - if it were, more people would hear it than not.   I'm absolutely not an ASR disciple, but I find some of the reviews and subsequent posts to be as entertaining and amusing as most current sitcoms.  A quote of note in the linked thread comes from ASR's leader Amir:  "if you have a high-quality DAC, there is no reason to anguish over how you are driving it."  I have no idea what he really means by that, since he doesn't say that he hears no difference among the many alternatives.  But I can't think of much in audio or most other areas that's truly worthy of anguish.  Some truly boneheaded actions deserve a little regret - but I strongly suggest reserving anguish for the seriously major stuff in life.

 

Even the Allo web page about it is confusing.  For example, it says clearly and specifically that "You can use anything on [the "clean" side], linear power supply or pure batteries power". But without including a SMPS on that list, they apparently don't really mean "anything".

[bluesman]

58 minutes ago, The Computer Audiophile said:

Absolutely. One of Amir's other disciples created topics here specifically to bad mouth AS and attempt to get people to go to ASR. Thus, I created a rule to stop the links from working. I also put the word science in quotes because it's only fitting. 

I was unaware of both this fact and everything associated with it, so I apologize for starting an errant topic.  But I suspect that no one will fail to understand my motivation for that link once you see the comments in the thread following the review. 

 

There are so many divergent opinions about the same device and the same issue (USB vs SPDIF) that I have no idea whether either alternative in either case (Signature vs "unsigned" microRendu and USB vs SPDIF) is actually different from the other in any way at all.  And so it is with the Raspberry Pi 4 vs other audio devices in the same role.  Either it's your slice of Pi or it's not.

 

I really got a kick out of the comments in that thread.  Here's just a tiny sample of the wacky world of internet audio comedy:

 

• "with a good clock coax is typically better than USB because of less noise"
• "SPDIF is just generally inferior to USB. So if you are hearing a difference it is just with additional distortion from the inferior SPDIF interface which is a clockless mess of light."
• "Thats wrong on so many levels its almost scary, I hardly know where to begin"
• "There is no way it can improve the sound on an rme adi. Likely it is making the sound much worse but you prefer the distortion."
• And there's this absolutely priceless gem:  "Ditch your shit motherboard instead of wasting money on nonsense audio products."

 

You could not make this stuff up if you tried!

[bluesman]

1 hour ago, Jud said:

Now that's solved, where do we want to go next? 🙂

In this thread, we want to go back to single board computers for audio

[bluesman]

8 hours ago, Archimago said:

Having said this, I think in an open forum it is useful to remind folks that more "objective"-leaning audiophiles would have no issue with what he said. And there should be little need for confusion. Provided one has a well-engineered DAC (which I will also add my Oppo UDP-205 and RME ADI-2 Pro FS as other examples), different digital sources that are bit-perfect will not affect sound quality whether it's interfaced through USB or ethernet. S/PDIF might be more prone to temporal drift and jitter, but again, a well-engineered DAC these days should perform excellently.

Thanks!  I have no issue with the statement itself. My issue is that it doesn’t actually say anything at all, let alone say what you said (and what I think but do not know for sure was meant by it), namely that SQ is unaffected - a statement with which you and I agree. Why oh why is it so hard to be simple?  Audiophiles, and especially many pundits and gurus, often hide interesting observations and good information in effete, purposeless prose that obscures rather than frames anything useful hiding within.  Like the country song suggests, I want a little less Shakespeare and a lot more Hemingway 😀
 

My aims in referencing that thread were to shed more light on Dave’s (davide256) observation about the SQ differences he heard between microRendu and Pi 3b+, to discuss his Pi USB concerns, and to consider his interest in the new “Signature” Rendu.   The strongly worded polar opposites that follow one another in that thread like insults from Don Rickles are, for me, ample support for what you and I are saying - and all 3 of my aims are touched within it.  
 

So here’s what I distill from this mash:  A well set up, normally functioning Pi or equivalent SBC will push a faithful bit stream into a DAC as well as anything else I’ve used - perceived SQ issues originate elsewhere in the chain between source and brain.  USB is not a SQ barrier if you power the DAC separately and don’t come close to the limit of available USB power with other peripherals (eg use external power if you must use a USB HDD or SSD).  An SPDIF HAT on my Pi will probably not make it sound any better, although I haven’t yet tried one and will do so - such opinions are better based on experience than belief.   And, parenthetically but to Dave’s observations, there’s not enough unanimity of opinion on the Signature to suggest to me that it’s going to sound better than the “unsigned” predecessor or a Pi. No, I’m not going to buy one to find out - I’ll suffer no anguish despite not knowing  
 

Thanks too for your approach and contributions! 

[bluesman]

28 minutes ago, firedog said:

Pretty much agree. But I can definitely see buying some thing like the USB Sig with the DigiOne Sig board. Why? You get what you know is a well made, hi-spec unit with a decent case, and a streamer that gives you both USB and SPDIF outs - a nice feature that few relatively inexpensive alternatives have. Each of us has to decide if the audiophile aspects of the allo products are worth the extra cost vs. a standard Pi with and addon board. 

+1!  But the best reason I can see for buying one is a desire to avoid DIY.  Having manufacturer and vendor support is another.  
 

Rolling your own is not for everyone, and a plug & play commercial solution is best for many people. In fact, after a week of frustration trying to solve a problem in something I built, repaired or modified (which happens at least a few times every year), I sometimes find myself anguishing ( 🙂 ! ) over not having gone with the flow.  Preferring what I made to what someone else made would definitely be a form of bias.........and I’m clearly without such affliction ( ).

[bluesman]

1 hour ago, firedog said:

hRaspberry Pi 4 Now Available With 8GB of RAM, 64-Bit OS

Sadly not yet in stock at my local Microcenter - I'm chomping at the bit to see how well this will work as a DAW with zram.  I get occasional breakup and stuttering even with a 4 gig Pi 4 when recording live music to wavs, if I'm using any plugins and monitoring the tracks as they're being recorded.  So I still have to monitor the input to be on the safe side, which is neither a big deal nor the ideal  

We live in hope!

[bluesman]

4 hours ago, R1200CL said:

......don’t forget the Squeeze Box Tuch 😂

 

An extremely nice endpoint and SQ is raised with a good PS. 

piCorePlayer does a great job with SB on the Pi.  It even works well on a Pi Zero W, which is an excellent choice for a tiny wireless renderer/player hanging from the USB input of a little pair of powered monitors.

[bluesman]

1 hour ago, mourip said:

Does any know if you can run Audiolinux on the RPi 4 Model B as a Roon endpoint?

 

Anyone tried it?

I haven’t tried Audiolinux so I can’t tell you that I know this from experience.  But based on AL website content and many web posts, I’d expect it to be excellent on a Pi 4 with Roon Bridge.