Pi2AES Impressions only thread

Thanks @haywood ! it was definitely a fun project. The only thing left is to deal with Squeezlite dropouts. Don’t know whether it is drivers or power or CPU settings tweaks yet. Will troubleshoot it step by step. Can be a dealbreaker.

Regarding

I prefer the sound with the transformer. Didn’t want to bring it up yet, because I tried it with basic Silent Wire cable only. The difference was pretty obvious, almost like changing a cable. Most interesting thing was that the stage shifted further behind the speakers. The sound lost tiniest bit of sparkle, became a bit less incisive. But microdetails (like reverberations, trailing ends of sounds) became more obvious and nuanced. Basically, it allowed to discern the stuff that I didn’t really notice with straight BNC connection.

A friend lent me the Oyaide 510 terminated with RCAs. And it’s the best option I tried so far in terms of resolution and 3D holographic staging. Didn’t try anything more expensive though. Gonna buy the BNC option and try this again.

Edit: @Woland thnks for the link. Read it after posting. Yeah, slightly less focused. I just picked up different words - incisive and sparkly. A couple of extra connectors isn’ta good thing I guess.

The differences are pretty small in the general picture. We’re talking cable differences here. I don’t know how to talk about it without somehow magnifying.

Edit 2: what I liked from the previous discussion, but not included before is “more analog sounding” and “more space between instruments”

Update: After some thinking, I can say that some differences aren't small in my opinion. From flat-ish, wide stage with Profigold cable to 3D, deep and holographic sound with Oyaide. Profigold sound so cozy and warm and "analog", like a nice vintage piece. While Oyaide has different kind of smooth - that can carry loads of resolution, but still without being grainy/incisive or taking the sound apart. I wouldn't call that a small difference. And that's only a digital cable. I bet on high-resolution speakers system even untrained listener would easily discern the difference. Just pick the cables from different sides of the spectrum, like the above two.

 

I've been using both 5v to pin 2/3 (Shanti) and clean 30v for several weeks each. I seem to consistently prefer the 30v, its more "solid", punchy and everything just a tiny bit better to my ears. I am using this (it's oldish, but I think they have a newer alternative):

https://www.diyinhk.com/shop/eol-pr...-dac-power-supply-regulator-91215v-15ax2.html

plus a r-core transformer from aliexpress, wired in parallel so 30v.

I also have an Allo Isolator below the pi2aes (because I already had it), difficult to tell if it pays off but at least the sound didn't get worse so it is staying. I've been keen on the usbridge at the bottom so thanks for input, but now I think I will wait as Allo is working on a new usbridge based on the pi4 compute module (instead of 3). I'm guessing a usbridge would make the isolator superfluous.

As a side note these look very interesting for cleanup of ethernet signal, but I already have a more expensive solution so not sure if I will gain anything. There is a lot of discussion about them on I think psaudio and audiophilestyle, believe it or not but the concept of cleaning up the ethernet signal works (at least in my, and many others systems): https://www.dxengineering.com/parts/dxe-iso-plus-2/specifications
Note that it is only 100mBit (as is my expensive filter).

The latest thing I did was put a small switch (dlink DGS-105) between the router and the pi. It sounds somewhat rediculous, but give it a try. Then power it with a clean 5v and be sure to ground it at the back. Point being that a router is a very polluting device.

Some of the changes are difficult to judge (as you probably know), but the sum speaks for itself. I've never had more holographic, deep (3d) clean sound with a huge soundstage. It often sounds as sounds are coming from all corners of my room, and what not. Using lyngdorf tdai-3400 for active crossover and tweeter amp, tpa3255evm for mid/bass amp and diy SB acoustics speakers.

 

Received this bad boy today. Seems to be solidly built, with subtle carbon fibre front and back plates and aluminum chassis!! (Picture on their website looks pretty ghetto like some carbon fibre vinyl sticky put on the front and back, the same vinyl sticky I used to stick to the bumper of my car when I was a kid!!!)
It actually looks pretty classy in person!!!

Appreciate the remark on the back “assembled and designed in Hong Kong everynight” !!!!! Comes with a stock AC and dc cable. Will let it run for a week or so and report back!!!

ps: it’s rated at 24v@1a and I plan to use it to power both the pi2aes and the rpi4 (with jumper)

Deric

 

Picture doesn't work, so we don't know what You received

 

It won't display directly on the forum. You need to open it separately in a new window.
https://www.amazon.ca/photos/share/Jf7gPWaq24P3SedagYBScyUHAAv0XXtZWD2jYyBRnKw

 

Sorry I bought a AFTERDARK low current LPS 24v@1A they made specifically to power the Giesemann OCXO 10M master clock, which i felt the low current version will also be great for my application to power my pi2aes. It’s got carbon fibre front and back shield along with aluminum chassis

Initial impression is this thing is dead silent!! I will report back after a week or so.

thanks

Deric

 

Here a new and very happy pi2aes user. Some info and findings in bullet style:

• Chain: pi2aes --> aes --> minidsp shd studio with Dirac (96/24) --> aes --> mutec MC-3+ usb with 10MHz aune xc1 master clock --> aes --> musician pegasus dac
• In spite of the pure source I find reclocking to still make a positive difference, especially for perceived soundstage
• Based purely on SQ, I prefer moOde to Volumio
• Connecting the pi2aes directly to my Musician Pegasus DAC via I2S is an option (and it worked) but in that case I could not use Dirac and would need to use moOde's SW volume control -- both not ideal.
• Perceived differences between AES/EBU, spdif RCA and toslink are small and could be related to the quality of the cables used.
• After briefly trying the stock PS, I used a Paul Hynes SR4 to feed the pi2aes with 19V (as I understand that anything from 14 to 48V will work). This was a clear improvement. Then I performed the PS tweak and now use an SR4T to feed 5V to pins 1 and 2 and ground to pins 3 and 7 (for extra gauge). This time I was not so sure about improvement. I guess this means that the pi2aes' internal switching works really well and that the Meanwell PS was the weak link. I might consider going back to clean 19V (see also svampebob's comparison above).
• I use no streaming services as I prefer playing local files for reasons of availability (my strange music taste) and SQ.
• I did some listening tests, playing from:
  (1) pc (JRiver or UPplay) to pi2aes UPnP
  (2) nas
  (3) usb drive connected to the pi2aes with a 15m fiber based usb cable
  (4) local usb drive
  (5) sd card (the same one containing the os)
  The perceived SQ increased from (1) to (5).
• So I decided to boot from a tiny usb stick and now use the sd card as dedicated music storage (no os). Not so elegant is that the usb drive with the os is now listed as 'SDCard' in moOde, but that is no big deal. Also copying files to the sd card seems a little faster this way.
• Network is CAT6-fiber-CAT6 with the PS of the downstream fiber-ethernet converter (currently a battery pack) especially important! But as always: the best network is no network, and deactivating the network when moOde is playing results in the best (open, smooth, relaxed) SQ. So that is what I do when playing longer playlists. I ordered an AC plug with RF remote that will enable me to turn on and off the downstream converter (and thus the network) from my easy chair. This way I can use the pi2aes 'stand alone' (as I did before with a NUC with wtfplay) and still have the conveniences of easy access and file copying.
• Also I have done some of the optimizations documented elsewhere by changing the config.txt file, such as underclocking, disabling wifi, bt, hdmi, network led's, etc.

All in all the pi2aes brings a welcome improvement to my setup!

 

Thanks for sharing your experience. I also find subtle improvements using a AfterDark Low current 24v@1a LPS connected to a Gotham 86215 power cable despite the unit is just burning in. And not much difference powering the pi2aes and the rpi4 separately.

I also agree to tweaking to rpi4 makes a slight improvement

Deric

 

PI2AES Production Update - 10/02/2021

The first 50 sold out quickly so we put the final 40 (we're keeping 10 back for support needs) in the store today. We still estimate deliveries will happen starting by the end of October. Not sure what we are going to do after these sell. Costs went up a bit and a few parts were harder to get. We would likely have to redesign around them if we decide to keep the PI2AES in production. And our price would need to go up again, so we'll see.

As to the status of Mercury, there is no change. As mentioned before all development is done and has gone very well. The plan is still to offer 50 Mercury Streamers with 4GB DRAM and 0GB SSD, and an additional 50 with 8GB DRAM and 1TB SSD. Price is planned for $499 for the 4GB/0GB and $749 for the 8GB/1TB. Full documentation and ordering info will be provided this week.

Many thanks for your continued patience from the Pi 2 Design team, and stay safe!

 

Re Hypsos LPS for Pi2AES:

Without first telling me his own impressions, Svampebob privately messaged me and suggested I try changing from the default 4T Sensing and Spread Spectrum settings on my Hypsos, which like him, I also use to power my RPi4/Pi2AES at 30v. Signals then go via I2S into my Metrum Onyx DAC with the new DAC3 module upgrade.

Quite independently of Svampebob and edwardsean on another forum, I can confirm that I found that turning both these settings to "OFF" gave me fuller bass, better soundstaging (wider and deeper) and above all, much smoother and cleaner treble. Recordings that I didn't like because of treble harshness are now more listenable. Well-recorded cymbals are now noticeably sweeter and more natural sounding.

I concur with Svampebob's suggestion of turning "OFF" 4T Sensing and Spread Spectrum when using a Hypsos LPS to power a Pi2AES at 30v. Admittedly this is going to be a very small group of Pi2AES users. These are very easy setting changes that are completely reversible if you don't like or don't hear an improvement.

Note that my system "may" be more resolving than most since I use an Uptone EtherREGEN just in front of my Pi2AES. My EtherREGEN is powered by its own Uptone LPS and I have an outboard AfterDark 10MHz master clock (Emperor Double Crown) providing clock signals.

Overkill? I don't think so - the Pi2AES seems to be up to the task.

 

I have been using my AfterDark 24v@1a Lps made for their 10Mz master clock, powered by a Gotham 86215 cable for more than a week now. I am very happy with the overall improvement compared to the stock meanwell psu. It is ultra quiet, definite improvement in overall sound stage, smoother mid and highs!!!

Deric

 

A lot of the additions people are making to the signal chain in front of the PI2AES and the raspberry pi itself, make me wonder are you comparing the sound quality to the previous change you made or back to the original unaltered version?

It would be useful to understand if these changes improve the sound compared to the stock power supply and the stock raspberry pi. Or do they just change the sound as each item is add it?

 

I listen to each change incrementally and then go back to complete bypass of front-end filtering/noise reduction/jitter reduction for a sanity check. The same thing applies to Pi2AES power supply. I still have your recommended Meanwell SMPS plugged in and available for a quick A/B. I have selected recordings with specific details in them to which I listen. Ears can be fickle, so I try to confirm previous impressions before I start accepting them.

 

perfect! Just to be clear. The Meanwell psu is not “recommended” so much as it is the compromise between performance and price.

 

Agreed - and for the price, it is an excellent compromise.

 

To be clear, I believe the changes I've made upstream of the Pi2AES affect my impressions of power supply changes. Without those upstream "enhancements", I'm not sure I would hear as much benefit to power supply upgrades. In other words, a cleaner input signal makes it easier to hear Pi2AES power supply changes.

 

I can report a huge boost in SQ of my RPi4/Pi2AES by replacing the stock fuse of my Hypsos hybrid PS with an SR Orange fuse - much fuller and tube-like sounding. Yes, I know - if I hadn't heard it myself, I wouldn't believe it either. Like tubes, mysteries of thin wires are hard to fathom. I'm not much of a believer in cable magic and this is my first experience with fuse rolling, but here I am. Go figure...

 

I also don't think the power supply changes are clear, unless you have a very resolving system.

Personally I test everything against everything, though I haven't been back to the meanwell for some time

I've been testing some more, and I always seem to find back to my diy power supply @30v.

At 5v I've tried
- Allo shanti, Ferrum hypsos
At 24/30v
- Meanwell
- Ferrum hypsos
- diy lt3042

The diy sounds the best to me, I've tried swapping many times. Going back to the 5v hack is always "meh", magic is gone.

I'm using this for 30v (it is deprecated): https://www.diyinhk.com/shop/eol-pr...-dac-power-supply-regulator-91215v-15ax2.html plus an r-core transformer @9vac. The never and better version is: https://www.diyinhk.com/shop/audio-...e-dac-power-supply-regulator-91215v-15a2.html. However diyinhk say that is it untested to connect it for 30v, so I am not too happy about it, though I've done it for half a year. It is completely cool and I doubt it gives problems.

But anyway I will therefore probably buy this one instead, which is tested at 30v:
https://www.mpaudio.net/product-page/md-hpuln-ps

Or maybe even the 10 x lt3045 version, which has even lower noise. The pi2aes deserves it!

I guess the conclusion to my ears is either or both of
- 30v is better than the 5v hack
- a couple lt3042 is very very good and better than Ferrum Hypsos

Referring Goldensound's measurements I don't quite understand the conclusion that the 5v hack is so good.
https://goldensound.audio/2021/07/22/pi2aes-streamer-measurements-and-5v-psu-mod-instructions/

The 2 last graphs show noise of stock psu vs ifi @5v. As I understand it all the spikes are the power lines 50Hz shining through (?). At 1k Hz the "bulk" of the noise is 50n vs 200n in favor of the meanwell. Is this not significant? Would this not exactly speak to using a good LPS instead of doing the 5v hack? It's only in the lowest frequencies the 5v hack is best.

I am not quite finished yet, I will also try separating the pi and the pi2aes to avoid the rf/emi. I know Michael don't believe it will yield anything, but it is cheap to try. Will probably try a gpio cable, maybe with a wall with copper tape between the units. If it seems to work maybe Ian Canada's StationPi.

 

I'm sorry, I see I am repeating myself in this thread..

 

Just to follow up; I had one of these lying around (23$):
https://www.ldovr.com/product-p/lt3045-a.htm

I put it after the Hypsos (outputting 8v) for the 5v mod, and to my ears this could be the best I've ever had. Everything is just amazingly clear and razor sharp.

For a cheapish and even better solution I guess one could use 2 of these in series - like 5v and 8v, and feed them with a 12v dc supply. Or 5-7-9. Each of them cleans the power up some more (I am not privy to downsides, for this use I don't think there are any. MPaudio also has an expensive version with double regulation). I believe lt3045 yields lowest noise with a 3v difference, though difference is not big. And the penalty would be more heat than with a lower difference, but since the pi2aes uses only 0,5w I would think it wouldn't matter. But someone please correct me if I am saying something wrong.

That's just to my ears The key is to use something with lt3045.

For a higher price these are just ready to plug in and use:
https://www.ldovr.com/category-s/123.htm