My new Boss - another PI-HAT

cdsgames

Member
2015-06-18 11:28 am
I am hopeful I can get the Boss sounding nearly as good or even possibly better than what I'm using now. AND I'm still very eager to hear the isolator boards from both Allo and Ian Canada... I suspect they will result in another lowering of the noise from the Pi and increase in SQ.

Following closely, thanks for all the great info so far!

Greg in Mississippi

Isolator board , I will have news in about 2 weeks...some components had crazy lead time .
 

sckramer

Member
2010-11-18 7:21 pm
I'm getting some reports from users that there is "clicking" when changing tracks that have differing sample rates.

Reference: Announce: piCorePlayer 3.20 Beta - Page 3

I normally upsample everything, so I've not heard this problem. Any thoughts as to where this is coming from? Does the Dac mute itself when changing rates?

@paul123, I think they're still tinkering with the drivers... lots of "mute" references in the code from just 3 days ago. And new option for MCLK/PLL enable/disable (Kali related).

Might be a bit premature to do a piCore release, need to let them finish up.

I was just happy to get a compile w/Boss for the first time and to see it in official... since the patches didn't work for me— but now know I missed adding it to the defconfigs... live & learn :)
 
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cdsgames

Member
2015-06-18 11:28 am
I'm getting some reports from users that there is "clicking" when changing tracks that have differing sample rates.

Reference: Announce: piCorePlayer 3.20 Beta - Page 3

I normally upsample everything, so I've not heard this problem. Any thoughts as to where this is coming from? Does the Dac mute itself when changing rates?

Yes we are aware of clicks noise when changing tracks . Seems to come courtesy of TI that removed the "click/pop " reference from pcm51xx datasheet about a year ago_Our IC batch is new and so it seems there is no antipop on the IC. Some ICs have louder clicks than others..
In any case we have modified (again) the driver and increase some muting..it works well.
 

TomWoB

Member
2017-04-06 7:12 pm
Hi all,

I just registered to this forum, because I like to read such useful threads!

And ... I want to tell that I'm very happy with the sound of my BOSS DAC, directly connected to my Lehmannaudio Linear and my HD650 ...

Attention: sckramer is wrong with his info (reply #104): (pin14,15 GND) (pin1,2 5V)
If you check the document, it's: (pin15,16 GND) (pin1,2 5V) ... pin14 is GPIO22 / MUTE_AMP

I attach two very detailed pictures of the BOSS DAC, where you can see all the details of the ICs, even the oscillators ...

As DimDim already mentioned, the LDOs are:
- LT3042 = LTGSH (picture)
- LP5907 = LLVB (picture)

Top.jpg Bottom.jpg

Best regards
Tom
 
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* DAC SW filters/DSP
O dear. Here's where IMO that TI PCM51xx falls short.
Best to go the 352,8/384kHz route to pass the filters by.
Same with internal VC. Best to leave it at 100%.

I also want to bypass the filter of the Boss by upsampling. I use picoreplayer 3.20. Do I understand correctly that it is best to upsample
-44,1 khz + 88,2 khz + 176,4 khz files to 352,8 khz
-48 khz + 96 khz + 192 khz files to 384 khz?

If yes what it is the commandline for it? So, how to create two upsample sets? I think it is not very difficult but I didn’t succeed. I hope you or someone else can help me!
 
Hi folks.

I added an article/howto to my blog related to

1. 384k upsampling
2. RPI/I2S-HAT/LMS/squeezelite

I also added some background info.

Enjoy.

Thanks for the write-up Soundcheck. I read through it and saw this comment:

Note:
I would not recommend to run CPU consuming upsampling neither on a RPI -
using squeezelite, nor a NAS nor on any other low performance platform.


I take it this means upsampling is a no-go for the RPI 3?

Thanks.
 
Thanks for the write-up Soundcheck. I read through it and saw this comment:

Note:
I would not recommend to run CPU consuming upsampling neither on a RPI -
using squeezelite, nor a NAS nor on any other low performance platform.


I take it this means upsampling is a no-go for the RPI 3?

Thanks.
Can't see how to edit my reply, unfortunately. It looks like I need to read up more on Squeezebox as it seems the upsampling is run on the server side not on the client side (RPI). Is this correct?
 

Greg Erskine

Member
Paid Member
2002-01-05 11:56 pm
Sydney
Can't see how to edit my reply, unfortunately. It looks like I need to read up more on Squeezebox as it seems the upsampling is run on the server side not on the client side (RPI). Is this correct?

Upsampling (on the fly) can be done on server or client. Soundcheck recommends doing it on a (powerful) server.

You may get away with doing the upsampling on a RPi3B if you don't have many players upsampling at once. It all depends on your personal requirements.
 
To add my 2ct to Gregs valid comment.

I try to avoid as much load on the Pi as possible.
CPU load (and inefficiency) and related distortions
can translate into sound degradation.

It therefore doesn't make sense to potentially gain
just a little because of 384k and on the other hand
loose more because of the local SRC.
Just give it a try. You've got the options.

And as I said. The best way forward is to run an
offline 352k8/384k conversion first.
From there all other options will just get you south anyhow.
If you don't experience any advantages, you better skip the
entire subject.

Good luck.
 
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Sorry been away so long!

1st, thanks Soundcheck for your work supporting this DAC AND your tutorial on upsampling!

2nd, thanks also to the piCorePlayer team for 3.20 Beta. Using that made finally trying out the Allo Boss an easy task... having the Boss driver included was critical, having GUI access to the driver's ALSA parms was great, being able to save those parms was super, and having the Audio-specific upgrades was a super bonus!

With the 3.20 Beta loaded, I finally got a chance to try the Boss DAC this weekend. I've been really happy with my modified HFBD+P over the past several months. I've been running it in slave mode on an Allo Kali, using 4 good power supplies, with 1 feeding the R-Pi, another the Kali, and 2 more feeding the HFBD+P's 5v and 3.3v separately. It was sounding very good this way and I prefered it to running it in master mode.

Based on this experience with the HFBD+P, I setup the Boss DAC on a Kali reclocker board with 3 good power supplies, again 1 feeding the Pi, 1 the Kali, and the 3rd the Boss.

It only took a couple of minutes to hear that it was handily beating my modified HFBD+P. I know I need to give it a couple of weeks for the parts to settle-in before I do any really serious comparisons, but some of the technical tweaks Allo included in the Boss seemed to be working very well.

While I'm burning it in, has anyone done comparisons between running the Boss in slave (on a Kali) versus master modes? Given the better clocks and power regimes on the Boss versus the HFBD+P, I won't assume it will be better in slave mode even though the HFBD+P works better that way for me.

Also, Soundcheck or anyone else, CAN the SOX upsampling be done on a LMS server running on a Window (8) PC? And if so, how?

Pretty pumped!

TIA!

Greg in Mississippi
 
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sbp

Member
2013-09-03 7:39 pm
Hi Greg in Mississippi.

It would be interesting to learn you opinion on upsampling via Soxr (Squeezelite) on pCP.

This can be done on the Squeezelite page - If you have a RPi3 I think that it will work quite well.
So it would be interesting to hear your experience and maybe compare it with upsampling on the server?