Thank you for your donation!


Allo BOSS2 DAC vs XMOS external USB DAC
#1
Hello,

until now I've been using Allo BOSS2 DAC + Allo SHANTI PSU paired with Airpulse A100 active speakers. These speakers have an USB input controlled by an XMOS audio processor.
My question is: sound qualitywise and in order to get things simpler, is it worth keeping my Allo BOSS2 DAC or just connect my Pi 3A+ or Pi 4B to the USB input of my speakers will do the same job ?

Thanks for your insights,
Romain
Reply
#2
Hello Romain,

The Boss2 DAC can only provide analogue (L+R) signal which needs to be fed to the AUX (or PC) analogue (L+R) input on your Airpulse A100 active speakers; given the fact that the Airpulse A100 is using a TAS5754 Class-D amplifier (one per channel) which is (in simple terms) a DAC+AMP in one package the analogue signal will be again converted into digital domain, etc.

I believe that it's not the matter of simplicity vs. complexity but the use of several electronic stages which may introduce extra distortion and/or noise in the case of the chain being Rpi + Boss2 HAT connected via RCA-to-RCA cables to the A100 active speakers. The other chain option is: RPi connected via USB cable to the A100 active speakers which will keep everything in the digital domain grace to the XMOS input.

I believe that you ought to test the two sets thoroughly so you can decide yourself which of the two will please your ears more.

Happy testing,
Mike
Reply
#3
Hello Mike,

I've compared both setups and found the sound more accurate/sharp with USB/XMOS than with RCA. I mean, it is really subtile and the sound is still very very good with RCA of course but it seems more tiring in mids and highs.

Some questions come in mind:

with the USB/XMOS setup, is power source as important as with the RCA setup ? Do I still need a quality PSU or a standard one is OK ?

I also have a pi 3 A+ and a pi 3 B+, is USB output as good qualitywise as with pi 4 B+ ? Is there any reason to use an USB 3.0 port for sound output on pi 4 B+ rather an USB 2.0 one ?

Thanks,
Romain
Reply
#4
(05-12-2022, 06:39 AM)romain Wrote: Hello Mike,

I've compared both setups and found the sound more accurate/sharp with USB/XMOS than with RCA. I mean, it is really subtile and the sound is still very very good with RCA of course but it seems more tiring in mids and highs.

Some questions come in mind:

with the USB/XMOS setup, is power source as important as with the RCA setup ? Do I still need a quality PSU or a standard one is OK ?

I also have a pi 3 A+ and a pi 3 B+, is USB output as good qualitywise as with pi 4 B+ ? Is there any reason to use an USB 3.0 port for sound output on pi 4 B+ rather an USB 2.0 one ?

Thanks,
Romain

Hi Romain,

You are well into the "here be dragons" territory on this.  You will find people who will argue both ways on all these things.  In truth any effect that such things have on the over all sound will be very subtle if they are there at all.  Try them if you can and see which you prefer (if you can tell any difference at all that is).  Most importantly, spend only what you can afford to throw away and enjoy the music.

Robert
Reply
#5
(05-12-2022, 06:39 AM)romain Wrote: Hello Mike,

............. snip............with the USB/XMOS setup, is power source as important as with the RCA setup ? Do I still need a quality PSU or a standard one is OK ?

I also have a pi 3 A+ and a pi 3 B+, is USB output as good qualitywise as with pi 4 B+ ? Is there any reason to use an USB 3.0 port for sound output on pi 4 B+ rather an USB 2.0 one ?

Thanks,
Romain

Hello Romain,

First of all... I stand corrected in relation to the two TAS5754 'raison d'etre' in the A100 active speakers: in fact one of them is connected in bridge mode for the left and right channel woofer and the other amp is connected in bridge mode for the left and right channel ribbon tweeters.

Now... if you use the direct USB set-up:
- the SHANTI psu is overkill (unless you are amongst the people taking the daily lunch at 'The Ritz'), if you have a standard RPi PSU handy a comparison test with the SHANTI will give you the info you may need
- I don't think that you need to use a USB 3.0 port for delivering data to the A100 active speakers (the 'simpler' RPi 3A stands out for being the lowest power-hungry)

My favourite set-up for the daily intake of music is composed of:
- RPi 3A
- USB hub
- USB-to-LAN converter (as I prefer LAN over Wifi connectivity)
- USB DAC
- headphone amplifier + over-ear headphones

May the Force help you find the right set-up for enjoying your favourite music  Angel
Reply
#6
(05-12-2022, 08:31 AM)CallMeMike Wrote:
(05-12-2022, 06:39 AM)romain Wrote: Hello Mike,

............. snip............with the USB/XMOS setup, is power source as important as with the RCA setup ? Do I still need a quality PSU or a standard one is OK ?

I also have a pi 3 A+ and a pi 3 B+, is USB output as good qualitywise as with pi 4 B+ ? Is there any reason to use an USB 3.0 port for sound output on pi 4 B+ rather an USB 2.0 one ?

Thanks,
Romain

Hello Romain,

First of all... I stand corrected in relation to the two TAS5754 'raison d'etre' in the A100 active speakers: in fact one of them is connected in bridge mode for the left and right channel woofer and the other amp is connected in bridge mode for the left and right channel ribbon tweeters.

Now... if you use the direct USB set-up:
- the SHANTI psu is overkill (unless you are amongst the people taking the daily lunch at 'The Ritz'), if you have a standard RPi PSU handy a comparison test with the SHANTI will give you the info you may need
- I don't think that you need to use a USB 3.0 port for delivering data to the A100 active speakers (the 'simpler' RPi 3A stands out for being the lowest power-hungry)

My favourite set-up for the daily intake of music is composed of:
- RPi 3A
- USB hub
- USB-to-LAN converter (as I prefer LAN over Wifi connectivity)
- USB DAC
- headphone amplifier + over-ear headphones

May the Force help you find the right set-up for enjoying your favourite music  Angel

Thanks Mike,

on my pi 3 A+, for the while, I use wifi connectivity for LAN and USB port for sound output but your setup is interesting. Dare I ask you which USB hub and USB-to-LAN converter you use please ? Is USB to LAN connectivity managed the same way as the ethernet one in moOde ? Is it possible to have a static IP address in this configuration ?

Romain
Reply
#7
(05-12-2022, 09:24 AM)romain Wrote:
(05-12-2022, 08:31 AM)CallMeMike Wrote:
(05-12-2022, 06:39 AM)romain Wrote: Hello Mike,

............. snip............with the USB/XMOS setup, is power source as important as with the RCA setup ? Do I still need a quality PSU or a standard one is OK ?

I also have a pi 3 A+ and a pi 3 B+, is USB output as good qualitywise as with pi 4 B+ ? Is there any reason to use an USB 3.0 port for sound output on pi 4 B+ rather an USB 2.0 one ?

Thanks,
Romain

Hello Romain,

First of all... I stand corrected in relation to the two TAS5754 'raison d'etre' in the A100 active speakers: in fact one of them is connected in bridge mode for the left and right channel woofer and the other amp is connected in bridge mode for the left and right channel ribbon tweeters.

Now... if you use the direct USB set-up:
- the SHANTI psu is overkill (unless you are amongst the people taking the daily lunch at 'The Ritz'), if you have a standard RPi PSU handy a comparison test with the SHANTI will give you the info you may need
- I don't think that you need to use a USB 3.0 port for delivering data to the A100 active speakers (the 'simpler' RPi 3A stands out for being the lowest power-hungry)

My favourite set-up for the daily intake of music is composed of:
- RPi 3A
- USB hub
- USB-to-LAN converter (as I prefer LAN over Wifi connectivity)
- USB DAC
- headphone amplifier + over-ear headphones

May the Force help you find the right set-up for enjoying your favourite music  Angel

Thanks Mike,

on my pi 3 A+, for the while, I use wifi connectivity for LAN and USB port for sound output but your setup is interesting. Dare I ask you which USB hub and USB-to-LAN converter you use please ? Is USB to LAN connectivity managed the same way as the ethernet one in moOde ? Is it possible to have a static IP address in this configuration ?

Romain

I reply to myself...will a such USB hub with integrated adapter do the job: https://www.amazon.fr/Aluminium-Adaptate...B09H2RD7MF ?
Reply
#8
(05-12-2022, 09:24 AM)romain Wrote:
(05-12-2022, 08:31 AM)CallMeMike Wrote: .....................snip..................

Thanks Mike,

on my pi 3 A+, for the while, I use wifi connectivity for LAN and USB port for sound output but your setup is interesting. Dare I ask you which USB hub and USB-to-LAN converter you use please ?

    By all means:
     - the hub is a non-descript one called USB 3.0 HUB with 4 data ports (plus a 'charging' port), an external switch-mode PS and (something that I also wanted) a POWER SWITCH; it was purchased from AmazonUK
     - the converter is a Rankie
  USB3.0 to Gigabit Ethernet Adapter


Is USB to LAN connectivity managed the same way as the ethernet one in moOde ?

     Yes...

Is it possible to have a static IP address in this configuration ?

    The answer is YES again...

Romain
Reply
#9
(05-12-2022, 09:49 AM)romain Wrote: I reply to myself...will a such USB hub with integrated adapter do the job: https://www.amazon.fr/Aluminium-Adaptate...B09H2RD7MF ?

I've replied a few of minutes ago to your earlier post with some details... as to your 'find' I suppose that the all-in-one gadget should do the job; the section 'Appareils compatibles' mentions Raspberry Pi as well as an arm's length of other devices.

<edit> I've just realised that 'your' all-in-one hub/converter gets the power from the RPi so some attention should be paid to the RPi's LPS/SMPS if you intend to plug other devices into the hub...
Reply
#10
(05-12-2022, 01:16 PM)CallMeMike Wrote:
(05-12-2022, 09:49 AM)romain Wrote: I reply to myself...will a such USB hub with integrated adapter do the job: https://www.amazon.fr/Aluminium-Adaptate...B09H2RD7MF ?

I've replied a few of minutes ago to your earlier post with some details... as to your 'find' I suppose that the all-in-one gadget should do the job; the section 'Appareils compatibles' mentions Raspberry Pi as well as an arm's length of other devices.

Thanks again Mike !
Reply


Forum Jump: