Allo USBridge musings

[davide256]

 SInce the USBridge is so affordable (cheap ) I've decided to do some playing around with it. Mine arrived today, ordered in the plastic case with the Allo DIetPi GUI.

 

1. packaging reminded me of when I got the Microzotl 2, no frills  (a la eBay), but well protected

2. basic setup  instruction sheet but like most less expensive items these days, the full instructions require internet access/download

3. case pleasing enough but side panels rattle a little. the transparent plastic case allows you to easily see the boards boot LED's

4. physical connection easy, USB and Ethernet at one end (make sure its the lower port on the bridge board, not the upper ports on the Sparky board), plug 5 V DC

    into the other end. Comes with a 5V wallwart but I didn't bother to use since I have an HDPlex LPS available.

 

At first listen I didn't find the sound to Schiit Eitr to be that much better than the DIetPi-PI3B+ with Hifiberry Digi+, all feeding coax to DAC. The sound was natural enough

whereas the 3B+/Digi+ combination tends to sound colored. But resolution was poor, details at top and bottom of audio spectrum faded out. Adding the ISO REGEN into

the chain helped quite a bit, retaining naturalness in tonality and remedying the detail fade outs at spectrum ends. Overall at this point it doesn't provide the micro-detail

resolution I remember from microRendu but it beats the Digi+ and iPhone  if the REGEN is in the chain. I'm going to let it settle in for  a few days, then pop the case and

try using different PS's for the two boards, do some hunting around to see if any tweaks emerge that could add to its performance. Tweak suggestions appreciated.

 

6/13 Note: I've switched to bridged Ethernet connection between streamer and server, doing so is like cranking up another notch of detail resolution with the USBridge, additive

to what the ISO Regen improves.

 

[hurka]

sclk ex clocked (Sparky Ultra):

usbridge-don't helps

iso R- just worse

tx usb ultra-don't helps

ultra low noise linear power,sps500,Lps1.2-Not my taste

Powerstor based ultracapacitor power-Hmm....I like That!!!!!!!!

[davide256]

11 hours ago, hurka said:

sclk ex clocked (Sparky Ultra):

usbridge-don't helps

iso R- just worse

tx usb ultra-don't helps

ultra low noise linear power,sps500,Lps1.2-Not my taste

Powerstor based ultracapacitor power-Hmm....I like That!!!!!!!!

 

hmm, whats your setup to do this " Sparky-sclkex/usbridge-sclk ex )"? Wouldn't surprise me at all if clock accuracy was the weakest point of the stock USBridge.

[hurka]

12 hours ago, davide256 said:

 

hmm, whats your setup to do this " Sparky-sclkex/usbridge-sclk ex )"? Wouldn't surprise me at all if clock accuracy was the weakest point of the stock USBridge.

think clock phase noise,not the accuracy.....

usbridge with sclkex also ok, if you don't have great sparky power.(but you need perfect usbridge power- more easy)

I just want reduce spaghetti ,and active components.

[davide256]

I've removed the power jumper so that now I'm powering the USBridge board with the HDPlex and the Sparky with an Ankar battery.  This helps, more incisive, detailed in the highs but hearing some edginess also in the highs. There's  a "performance" option in the GUI to turn off CPU throttling, would have liked to try that but when I chose it the result was a script error dialog, option remained in balanced setting. In general I don't trust throttled settings as they can interact with playback.

 

Haven't figured out yet how to bypass the Allo GUI, would  like to disable it and run the device with the greater control allowed under dietpi menu. Also noted that the DAC 1.1 setting caused an abort during playback so sticking with the normal DAC option selected. Given the high cost of an sCLK-EX board I don't think I'll go that route, could get an ultraRendu for only $200 more

[davide256]

have solved the high frequency harshness by enabling the ISO REGEN as +5V to the Eitr. Overall the sound is very listenable, good dynamics, tone color.

Where the microRendu would badly trounce the USBridge is in decay time of notes. The USBridge seems to cut or blur the decay of notes during dynamic

(ff or fff) sections whereas the microRendu had proper decay even during the loudest of passages.

[davide256]

Running the USBridge now with the Dietpi image from the Sparky site, booted from SD card slot. This allowed  better control over settings, versus the walled garden of the Allo GUI. Network working fine with an Edimax WIfi USB stick, happy to cut the wired Ethernet tether. Have swapped the HDPlex around to power the Sparky board and run the USBridge board off the Ankar battery.

[chauphuong]

Any guide to remove the on board smps and directly provide linear 5v,  3.3v and 1.8v to the board (just like with Pi) yet? 

[davide256]

On 4/24/2018 at 10:37 PM, chauphuong said:

Any guide to remove the on board smps and directly provide linear 5v,  3.3v and 1.8v to the board (just like with Pi) yet? 

There is a jumper on the USBridge board, if removed you can power Sparky and USBridge board with separate 5V DC power supplies. Not aware of any other option.

 

Also in regards to PS, I am now finding that the PS for ISO REGEN is critical in my chain; swapping the SoTM SPS500 in at 7V DC to power the ISO  REGEN is significantly clearer and easier to listen to than using the  HDPlex to power.

[Superdad]

On 5/5/2018 at 7:52 PM, davide256 said:

Also in regards to PS, I am now finding that the PS for ISO REGEN is critical in my chain; swapping the SoTM SPS500 in at 7V DC to power the ISO  REGEN is significantly clearer and easier to listen to than using the  HDPlex to power.

 

Hmm, guess it obvious what you really need to power the downstream side the ISO REGEN--ultra quietly and without introducing a new AC-connected supply or leakage...

[davide256]

39 minutes ago, Superdad said:

 

Hmm, guess it obvious what you really need to power the downstream side the ISO REGEN--ultra quietly and without introducing a new AC-connected supply or leakage...

Yup,  the ISO REGEN is providing downstream USB voltage. Looks like I'll have to pull the trigger on another good PS soon for the ISO REGEN as the SPS500 really sings powering the Microzotl 2... the HDPlex can pinch hit but it lacks the authority that the SPS500 current reserve provides.

[davide256]

Replaced the Ankar battery, now using a 5V iFi PS for the Sparky board and running the USBridge board off the 5V HDPlex tap. Looks like battery while quiet

doesn't  provide what the USBridge needs for good bass transients as they are significantly improved. Oddly with J28/29 open it looks like the Sparky is still booting with

power connected only to the USBridge, can see the red boot diode pulsing and the wifi dongle flashing if I wait before plugging the iFi PS into the micro USB port on the Sparky board.

[davide256]

Ok, pulled the trigger on an LPS 1.2 so I can play around some more. Going to try the following

 

1. compare SoTM SPS500 vs LPS1.2 powering the ISO Regen

2. compare LPS1.2 powering the  USBridge vs the HDPlex

 

The main thing I find  unsatisfactory about the USBridge is that choral voices sound raw and edgy, will see if option1 or  2 with the LPS 1.2 corrects

[davide256]

Received the LPS1.2 today, have done some preliminary swapping around but need to put some hours on it before serious comparison. The one glaring thing out of the box

using the LPS 1.2  is that sound is cleaner, some  low level fuzz and irritants present in playback using the SPS-500 are gone.

[davide256]

So some conclusions after burn in and playing around

 

1. No surprise on the LPS1.2 vs SoTM SPS-500 powering ISO Regen; the  sound is better articulated when  using the LPS 1.2 with Regen  vs SPS-500 and HDPlex

powering the Allo USBridge.  Doesn't fix the audible harmonic flaws though that the USBridge/HDPlex PS combination has

2.  with the SPS500 powering the ISO Regen,

the LPS 1.2 sounds immensely better driving the  Allo USBridge  than the HDPlex, cleans up the  harmonic distortion ever present using the HDPlex as PS.

Best sound comes from dual use with J28/29 jumper open, HDPlex powering the Sparky, LPS 1.2 powering the USBridge board. The LPS 1.2 can drive the device by itself but

there is an impression of slight transient dulling and strain that disappears using both.

 

[davide256]

I'm now using bridged Ethernet with  USBridge but I have been having  random BSOD crashes when I try to use the PC server  for web browsing. I think I've solved it,

was "predictably" having a random crash within 30 minutes of opening a browser or at system shutdown, have now been able to run  for 4 hours and restart without a crash

despite multiple browsers open

 

Allo port is FE, built in MOBO port is GigE. Believe network bridge is related to the ethernet  port multiplexing driver and for that all ports must be same speed. After

restricting speed to 100mbps/full duplex on both ports all seems well.

@austinpop    you may want to verify this for possible inclusion in the summary note mentioning network bridge for "the thread that never ends". 

[austinpop]

20 minutes ago, davide256 said:

I'm now using bridged Ethernet with  USBridge but I have been having  random BSOD crashes when I try to use the PC server  for web browsing. I think I've solved it,

was "predictably" having a random crash within 30 minutes of opening a browser or at system shutdown, have now been able to run  for 4 hours and restart without a crash

despite multiple browsers open

 

Allo port is FE, built in MOBO port is GigE. Believe network bridge is related to the ethernet  port multiplexing driver and for that all ports must be same speed. After

restricting speed to 100mbps/full duplex on both ports all seems well.

@austinpop    you may want to verify this for possible inclusion in the summary note mentioning network bridge for "the thread that never ends". 

 

Hah! I never have, nor do I ever intend to, verify all reports of bridging successes and failures. That way lies madness!

 

Best would be for you to post on that thread the exact config of the machine you're bridging - OS and version, all the network adapters you tried to bridge (preferably both brand and chipset) and then what worked (or didn't work). If you do, I'll be happy to add this to the index as a configuration where "beware, there be dragons." Who knows, someone may even be able to advise you on a fix or workaround.

[davide256]

Still tinkering with the USBridge. I've learned that the two boards really aren't isolated for power if you open the jumper... as long as there is power connected to the USBridge board, the RPI will get power and the USBridge will run fine. With that said, best sound was gotten putting  better PS alone to the USBridge board, if I used

a second PS that was not as good on the Sparky board, it degraded sound to the level of the second PS.

Sadly the LPS 1.2 cannot power USBridge and  ISO Regen together.

Juggling the PS's I have, best sound now gotten with HDPlex at 5V powering USBridge, LPS 1.2 powering the ISO Regen at 7 V  with the 5V replace switch enabled.

and the beefier SPS500 powering my MZ2 and 4 port network switch at 12V.

[Lukasluis]

I received the USB Bridge today and straight away removed the jumper then powered the Usbridge with LPS1 and the Sparky with a low noise Battery supply. The Usbridge is connected to DAC via ISO regen powered by the same LPS1 (I used a Y-cable). 

 

I find the sound to be very shut in and downright boring. Sounds like low quality CD player. The iPad sounds more engaging and lifelike. My heavily-tweaked Dietpi running on RPI3 with bypassed fuse and regulator and powered by the same LPS1 sounds more musical to me. I use them as ROON endpoint. 

 

Where could be the issue? Could it be the result of too much filtering? 

[davide256]

6 minutes ago, Lukasluis said:

I received the USB Bridge today and straight away removed the jumper then powered the Usbridge with LPS1 and the Sparky with a low noise Battery supply. The Usbridge is connected to DAC via ISO regen powered by the same LPS1 (I used a Y-cable). 

 

I find the sound to be very shut in and downright boring. Sounds like low quality CD player. The iPad sounds more engaging and lifelike. My heavily-tweaked Dietpi running on RPI3 with bypassed fuse and regulator and powered by the same LPS1 sounds more musical to me.

 

Where could be the issue? Could it be the result of too much filtering? 

Can you run the entire USBridge off the battery? While PS matters for the USBridge, where I've landed is using LPS 1.2 entirely for ISO Regen with the USB 5v replace switch  enabled. Curious to try battery supply now vs the HDPlex, I have an Ankar battery for tablet charging that should work

[Lukasluis]

44 minutes ago, davide256 said:

Can you run the entire USBridge off the battery? While PS matters for the USBridge, where I've landed is using LPS 1.2 entirely for ISO Regen with the USB 5v replace switch  enabled. Curious to try battery supply now vs the HDPlex, I have an Ankar battery for tablet charging that should work

I found that after disabling all services except ROON there are still 32 processes running as compared to only 16 processes with RPI3. For a start, I have limited the CPU to 720MHZ (min and max). This helped a bit in opening up the sound. I will also tweak the priority levels in Process-tool and gibe Roon tasks highest priority and cpu affinity. Hope that will help. 

[davide256]

6 minutes ago, Lukasluis said:

I found that after disabling all services except ROON there are still 32 processes running as compared to only 16 processes with RPI3. For a start, I have limited the CPU to 720MHZ (min and max). This helped a bit in opening up the sound. I will also tweak the priority levels in Process-tool and gibe Roon tasks highest priority and cpu affinity. Hope that will help. 

Allo config pretty much starts with all media player types enabled, so makes sense to disable what you aren't using, I've done that. Hadn't fiddled with process tool, will give that a try

[Lukasluis]

19 minutes ago, davide256 said:

Allo config pretty much starts with all media player types enabled, so makes sense to disable what you aren't using, I've done that. Hadn't fiddled with process tool, will give that a try

I have given the 3 Roon tasks 1 Core each and the rest to the remaining 1 Core. I also changed the Priority of Roon tasks to highest and schedule to FIFO. CPU is now peg to 504MHz. With the lowered frequency, the LPS1 can now power both the Bridge and Sparky and also the Iso Regen. It sounds very much nicer now as compared to before. I will image the emmc card then will uninstall unnecessary programs such a samba and webservers programs.