Acer C7 Chromebook $199 at Walmart runs KXStudio W/ JACK!

Unofficial support for the KXStudio Linux distribution and applications.
More info at http://kxstudio.linuxaudio.org/

Moderators: khz, MattKingUSA

tbritton
Established Member
Posts: 33
Joined: Sun Jan 29, 2012 4:22 am

Acer C7 Chromebook $199 at Walmart runs KXStudio W/ JACK!

Postby tbritton » Mon Aug 19, 2013 4:48 am

This may surprise you as much as it surprised me... Special thanks goes to David Schneider (dnschneid) who started crouton and to drinkcat at the crouton issues list for finding out some important details concerning turning off the Chrome Audio System (cras) so you don't inadvertently make strangeness happen by accidentally playing sounds in Chrome OS. Note: Not all of this will work with a Samsung ARM processor! But JACK audio seems to work if you turn off the Chrome Audio System (cras) with sudo initctl stop cras as described below. Just don't try installing the KXStudio repos to an ARM device - you'll have to manually do that grunt work.

This project is for Chromebooks with i386 processors.

I have a fully working installation of KDE KXStudio running on a 3-pound, $199 Chromebook! This is the Intel-inside Acer C7 currently at Walmart and other locations for $199 - making it - when working in conjunction with a crouton linux KDE chroot and KXStudio installed from the Ubuntu:Upgrade page - the least expensive full-blown audio workstation in the world!

First, take your Chromebook and place it into Developer mode (Do so at your own risk, etc.). This model does it from software rather than a hardware switch like some other models. You press the escape key, F4 (reload) key and power button at the same time to reboot into a special mode, then press CTRL-D when the "Broken Chrome OS" screen comes up and wait a moment. Press Enter from the page that appears to be led into the creation of the Developer mode. When it re-boots, you'll be at a "scary face" page -- just hit CTRL-D to get past it and connect to your Wifi and create your login. If you've synced all your settings with other machines, all of your settings will come back after about 5 minutes. But... we're after a linux installation next! Watch a video of this all being done here -- except we're installing KDE rather than XFCE since KXStudio runs best with that.

This version of linux - crouton - actually runs a desktop installation over the top of the existing Chrome OS linux (yes, Chrome OS is a linux desktop with drivers built into its custom kernel). First, go download it to your Downloads folder here:

http://goo.gl/fd3zc

and read the ReadMe page and the Wiki page:

https://github.com/dnschneid/crouton/blob/master/README.md

https://github.com/dnschneid/crouton/wiki

Now hit CTRL-ALT-T to enter crosh and type in

Code: Select all

shell
and hit enter to get to the command line.

Install a 12.04 KDE desktop using this command next:

Code: Select all

sudo sh -e ~/Downloads/crouton -t chrome,kde -n kxstudio -r precise


It takes about 10-15 minutes on a fast connection.

Enter your new KDE installation now by typing:

Code: Select all

sudo startkde


Now go to the KXStudio:Ubuntu:Upgrade page and run all the commands there in your terminal. You may need to install synaptic to get the ppa command to work (I did):

Code: Select all

sudo apt-get install synaptic


Do install the KDE4 ppa as well. (in the instructions page)

After everything is installed, log-out and it will bring you back to the Chrome OS.

Type in this at your crosh shell prompt to turn off the Chrome OS system audio:

Code: Select all

sudo initctl stop cras


It will return:

Code: Select all

cras stop/waiting


Now enter your KXStudio installation with:

Code: Select all

sudo startkde


Navigate to the KXStudio Welcome Page in System a little ways down and force the settings to be updated, and go ahead and apply the KXStudio theme.

Now log-out and

Code: Select all

sudo startkde
again and you'll be in KXStudio!

BTW - you can return to the Chrome OS with the key combo CTRL-ALT-Backarrow(F2) (or on some machines, CTRL-ALT-SHIFT-Backarrow(F2)) and return to KXStudio with CTRL-ALT-SHIFT-Forwardarrow(F3). So, you get a full Linux with your Filezilla and KXStudio and Skype and your Cloud Machine Chrome OS all running so you can switch between the two in a flash!

JACK worked from Cadence after manually starting it (auto-start does not seem to work), but I had to go into the ALSA mixer to turn on my headphones at one point (they muted themselves) - You might want to add the Speakers volume control also, but probably not necessary.

If you are running JACK on an ARM based Chromebook, like a Samsung, then you'll need to definitely shut off cras to avoid a bad restart-causing crash coming about from trying to run the two sound systems at the same time.

Here are notes from the conversation I had with drinkcat at the crouton issues thread:

In KXStudio using Cadence to control Jackd, the JACK server starts fine and
I can get playback from VLC set to output to JACK if I have the Alsa Bridge
Type setting to:

(None) "No Bridge in Use"
OR
ALSA ->PulseAudio->Jack(Plugin)
OR
ALSA->Jack(Plugin)

The ALSA->Loop->JACK setting does not work - that is, it attempts to start
but then fails without an error message. I do not know if I'll need it, as
VLC allows direct connection to JACK from its Audio preferences.

Happiness with VLC, then! It can play directly into JACK with the ALSA
bridge set to None. When I stop the Jack server, the audio stops as well.
Start Jack and I can re-start playback with VLC.

Even with JACK stopped Rhythmbox plays as normal. Rhythmbox seems to play
through ALSA, so it does not care whether JACK is started or not (but
manually stopping a running JACK server will crash Rhythmbox... that stops
the audio, but is unrecoverable and requires a terminate command).

The final test is with Ardour.

Yay! Ardour works! We've got a mean audio machine here now! This is pretty
amazing!

I think my problem earlier was actually not with the CRAS server, however.

I just did a test without trying to stop cras and all ran just fine (on an
Acer Chromebook C7 - the $199 Walmart edition running Intel). What you have
discovered possibly applies only to the Samsung ARM processor based
machines. (But perhaps it is still quite important to not have to audio
systems running at the same time... crashes or no crashes.)

I think it was my confusion over the ALSA->Loop->JACK setting not working
that may have been causing my lack of sound - that is, you'd hit Start and
the startup would fail. I did not at that juncture attempt other settings
(like None) because I always had used the ALSA->Loop->JACK setting.

When I run

Code: Select all

sudo initctl stop cras

I get the message

Code: Select all

cras stop/waiting

That is in the shell before running
the KXStudio kde chroot.
Then I typed

Code: Select all

sudo initctl start cras

and got

Code: Select all

cras start/running, process 26026

-- so I suppose that tells me what process to kill if I want to stop it
that way. But, like I said, even without stopping cras, JACK is running and
I can hear AND record audio from VLC and Ardour. (My internal mic was on by
default, so I could see it in the meters in Ardor and hear it in the
headphones when I bumped it! Whoops! Watch those inputs!) :-)

It probably is a good idea to stop cras while using the audio in KXStudio, but I'm not certain I am accomplishing this or not. Does cras stop/waiting indicate success?

drinkcat commented:

I believe the output you get means it worked. You can always verify if cras is running with something like

Code: Select all

ps -eaf | grep cras


And yes, I would stop cras before starting JACK. It may not be fully necessary, but strange things may happen if you try to play sounds in Chrome OS (even inadvertently).


Run that last command drinkcat mentioned in the crosh shell before starting up KDE/KXStudio - it was worthless running it in KXStudio's terminal (to me at least!)

I've upgraded this Chromebook to 64 gigs of SSD drive space and added another 2 GB of RAM - instructions here - but that's because I'm crazy and just wanted a 3-pound killer writing machine originally that is now a killer audio/video laptop to play with! The stock system will work, but don't fill up Ardour with too many tracks on the stock machine!

People will not BELIEVE you are doing this on a Chromebook, my friends! :-)

Terry
Last edited by tbritton on Mon Aug 19, 2013 8:41 am, edited 2 times in total.

danboid
Established Member
Posts: 1305
Joined: Sun Aug 26, 2012 11:28 am
Location: England

Re: Acer C7 Chromebook $199 at Walmart runs KXStudio With JA

Postby danboid » Mon Aug 19, 2013 8:15 am

If you are running this on an ARM based Chromebook, like a Samsung, then you'll need to definitely shut off cras to avoid a bad restart-causing crash coming about from trying to run the two sound systems at the same time.


Wha? I didn't think F made KX packages for Debian/Ubuntu armhf?

Maybe you're talking about running KX on a ARM chromebook under qemu or something, which would be unusable and silly.
Are you new to Linux Audio? This manual explains how to install KXStudio, set up and use JACK, mimimize latency, lists the best Linux AV apps and much more all in a concise and easy to understand format.

http://wiki.linuxaudio.org/wiki/kxstudio_manual

tbritton
Established Member
Posts: 33
Joined: Sun Jan 29, 2012 4:22 am

Re: Acer C7 Chromebook $199 at Walmart runs KXStudio W/ JACK

Postby tbritton » Mon Aug 19, 2013 8:35 am

danboid,

No, you are correct - the KXStudio repos will not work on ARM processors. I'll edit the post to state that clearly.

However, to run Jack they will need to stop cras presently, though that may be fixed soon.

Terry

devilock76
Established Member
Posts: 84
Joined: Fri Feb 11, 2011 4:31 pm

Re: Acer C7 Chromebook $199 at Walmart runs KXStudio W/ JACK

Postby devilock76 » Wed Mar 12, 2014 2:10 pm

Just an add on to this. I recently purchased the HP Chromebook 14 4g (the one with free t-mobile for life and 4gb ram).

Using crouton I installed Debian Wheezy and added the deb-multimedia and KXStudio repos. Jack2 and Cadence work well, pretty much everything works as expected on a linux install on hardware like this. Even though Chrome OS does not recognize USB Midi, it is passing the data to the chroot install so a2j was able to pick up my Akai MPK49 and I had stage quality latency playing through several soft synths on the machine. Obviously hard drive space is an issue. I am adding a 32gb usb 3.0 drive too this setup. One to store DJ song lists and samples as needed. I would probably just use it for offline sample store though Anything I am actively using I would probably prefer on the machine for fast access. But we shall see. Aso I will use the usb to store a backup image of the chroot install. Just in case I break something in tweaking or god forbid the space bar gets hit on boot up.

Truth be told I am rather impressed so far with the functionality on hand in this format. Great battery life and performance in a sub $400 machine with no MS or OSX tax. Granted there are compromises but I was really looking to scale away from my ipad for doing work. I find myself "playing" more than working on my ipad and I needed a machine that could go all day on battery if need be and actually do work. Be it coding work or document work or research work or music work. I have about a week and a half to see if I will keep this before my return window ends (Walmart was the only local vendor). So far I am mixed, but the fact remains that so far I have not found myself hitting a wall where I couldn't do something that I would normally do on my main laptop (older toshiba dual core, a205 I think). Granted it is heavier than lugging the ipad around. However in many cases where i would have lugged y toshiba out the ipad would have been with me anyway. The only downfall in that case would be if for some reason I had to connect to a machine with itunes I would be out of luck. But you know what, that is something I avoid doing on the road like the plague. I only do that from home and in the 18 months as an ipad owner I can tell you I have had to connect it to itunes less times than I can count on both hands.

And to mention, even before you jump into a chroot the possibilities of the chromeos on its own (especially with an internet connection available) are very impressive as well. 99% of my time on a computer is with an internet connection available, so that 1% of having the free t-mobile sim as a backup is great as well.

I wouldn't really recommend a machine like this for multitrack recording. Maybe field recording with a fast external drive. But as a mobile synth bank with a controller o general composition tool I see it going a long way for most users in the linux audio realm.

Ken


Return to “KXStudio Discussion”

Who is online

Users browsing this forum: No registered users and 3 guests