New Squeezebox Touch Mod

[RotelMan]

Tip:

If you feel the sound is a bit too clear for your system just back down on the "SPDIF" value a bit.


Enjoy!!

Hi again... I have now also disabled Samba and WLAN and it gives me a better sound balance... Big Thanks from Denmark :-)
I'm also running Soundcheck toolbox 2.0

If I want to back down the spdif value... do you then have f.ex. a IRQ value I can try?

[tufty]

Thanks for sharing this mod. I have already installed soundcheck's toolbox 2 with impressive results. However, I am using WLAN... does your mod work if I skip this step, or will wireless streaming be compromised?

[dynaudiorules]

Hi Tuffy,

The mod works regardless if wlan is enabled or not. Wireless streaming will not be compromised.

[castalla]

Reducing 'sharpness' .... any suggested values?

[dynaudiorules]

Try 53 for "spdif", you may also like to try other values for "spdif" to suit your particular system and tastes...usually between 41-59.

[JohnSwenson]

Just a caution, the process numbers are not carved in stone, as you comment or uncomment things in rcS or change hardware configuration (such as running off a USB disk), some of those process numbers can change.

So I highly recommend running the command

ps -eLo pid,cls,rtprio,pri,nice,cmd | grep -i "irq"

as listed in the instructions to find out what process numbers are used for a particular interrupt on YOUR system. Use those process numbers in your modified rcS file.

The IRQ numbers for a particular device seem to stay constant no matter what, but the process numbers do change if you change the system. From one boot to the next with a particular system configuration the the process numbers DO stay the same.

Just remember that if you change your hardware configuration there is a very good chance some of those process numbers will have to change in the rcS file.

John S.

[dynaudiorules]

Thanks John,

I will stress the need to make sure the process ID is the same.

Perhaps an easy way would be just to use `pgrep spdif` for example instead of the ID numbers.

[alec_cat]

Hi again, Dyn. I was wondering, are those 5 processes the only that may have a bearing on performance? I tried looking some of them up on alsa and linux websites but some of them are not terribly descriptive.

I would have supposed they're all significant to some degree - clocks, ethernet, spdif, etc. Mind boggling!

As an aside, and this is very hard to be objective about, but I think I'm doing pretty nice in my system with chrt -f -p 44 367 for the spdif priority - a nice balance of clarity with smoothness - a tad less etched than 59. I wonder if anyone could give that a try and their impressions?

[dynaudiorules]

Hi alec,

For the purpose of audio I was only interested in audio related processes. Again these are tweaks I previously used on my Linux machines. They proved to make Music Player Daemon sound really well so I just used them on the Touch. For the Touch it would appear that the etho IRQ would be important however I was not able to isolate that process. Also because the server does some work with the audio 'bits' I applied the same tweaks [and more] to the Linux server as well. However I have been building a cMP2 machine to use as the Squeezebox server just to see if it makes a difference.


Thats great alec that you were able to find a value that suits your tastes and system, I encourage everyone to do the same because we all have slightly different tastes and most likely different systems as well. A bit of fine tuning is a great idea.
Cheers

[dynaudiorules]

Would be nice if we had a 3rd party app that provided a few different filter settings that toggled the spdif value....say 44, 48, 53, 59 for example.

I don't know about you but if I have music playing while I change the value I can actually hear the difference fade in...

One thing about this mod is that it is clearly audible.