rakarrack, qjack, ubuntu connections

Configure and optimize you computer for Audio.
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I just converted a laptop over to Ubuntu 12.0.4 (my first Ubuntu experience). I found Rakarrack which looked awesome, discovered it needed something called qjack which I also installed from the ubuntu software center. Now when I plug my guitar into my laptop using a standard 1/4" jack to the guitar with a 1/4" to 1/8" converter on the other and plugging it into the microphone jack, the input and output bars bounce up and down and the tuner in Rakarrack actually works - but I hear NOTHING. I can't seem to figure out what connects to what in qjack (I've looked at diagrams which seem totally different from what is on MY computer)and am absolutely clueless. Rakarrack LOOKS awesome - but I can't get it to work. HELP!!!!!!!!!!
whippet6

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These should help

https://help.ubuntu.com/community/HowTo ... onnections

https://help.ubuntu.com/community/HowTo ... figuration

qjackctl is the gui for the jackd sound server, start it, and click Setup,
A page with three tabs opens, Audio, Midi, and Alsa.

Each has an input panel, and output panel. Audio software that supports jackd
(most linux audio apps) and audio hardware recognized by the kernel, will
appear. You must highlight an item on each half, and press the Connect button,
to draw the 'cable', output, to input, input to output.

In the audio tab, click the little widget to the left of System.
'System' is your computer sound i/o connection. Clicking the widget expands
the full list of available i/o

Rakarrack may connect automatically, perhaps in mono, if so, to get stereo,
you just select the one input, and the second output, and press the
disconnect button. Then select the second input, and the second output,
and press Connect. Go to Rakarrack preferences, to make this the default.

The guitar pickups won't likely send a loud enough signal to the computer,
so an interface, or soundcard, will help boost it to line level, or provide
a usb connection for recording/playback. These work in linux

http://www.musiciansfriend.com/pro-audi ... -interface

If your computer has a line-in jack, use that instead of the mic jack.

Open a terminal, and type these commands, and save their output as a text file
for future reference, they will show what your various chipsets and kernel modules
are available, and help you choose your computer sound chip(s) in qjackctl

cat /proc/asound/cards
aplay -l
arecord -l
aconnect -i
aconnect -o
lspci
lsmod
'
The jackkd wiki page is a bit old, so 'Force 16bit' box should be unticked, and 'Timeout (msec) 5000' can be between 200 and 1000, rarely an issue.

Input Device and Output Device
each have a > widget to click,that shows a dropdown list of available sound hardware. If you hear nothing, even when connected, the mixer may be muted,
or look at the output of arecord -l, for a name or phrase in brackets, and type that in the Device fields, without the brackets. It mat say Intel,
or Generic, etc

lsmod output might include a module like snd-Intel-Hda for sound, along with
the modules it uses, and modules that use it.

The Rakarrack 'Help' file, is very good!. search Youtube videos for hydrogen and ardour, 'ubuntu studio', which often will start with the qjackctl the process,
follow the sidebar vids for more.

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about the 3 tabs, Audio, Midi, and Alsa

Alsa is your system midi, most synths, and audio apps will open
midi ports there. A midi keyboard would be on the right, and
computer midi port on the left. Select each, and press connect.

The middle Midi tab, is for jackd midi ports, which some instruments need,
and many will use it, if available. For this port to appear, start qjackctl,
run the command

a2jmidid -j default

If you don't have that command yet, download the package here:

http://packages.debian.org/unstable/sound/ its first in the list :hihi:

click the link, you will go to a choices page for cpu, architecture,
choose based on your computer, and ftp site list opens, click one
near you. The downloaded file will have a .deb extension.

To install this, the command

sudo dpkg -i nameXXX.deb

When another software is also needed, you will be told what it is, fetch
that one too etc etc

The Audio tab has your soundcard i/o, connect system on the left, to system
on the right, to hear sound. Rakarrack output is on the left, your
soundcard output (speakers/headphones) is on the right, select each, press connect.

But the Rakarrack Input on the right, still needs to be connected to your
soundcard input on the left, so connect them, the cables drawn will form
a big X. Easy money :wink:

Rakarrack presets vary in output volume, so be careful first time through.

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Thank you very much. I thought my internal sound card should handle it via the mic input (I have no line in on my laptop). But I suspect that the guitar pickups did not put out enough power which is what you pointed out. I'll have to get the guitar/ USB connection from Musician Friend. Again, thanks for your time and help.
whippet6

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get a Fender Mustang usb amp, about $100, it connects by usb, linux sees it
in qjackctl by name, it sounds great, a dial switches between 24 sounds you can edit/create with 'Plug'

http://piorekf.org/plug/

or use the windows/mac Fuse software it ships with.

The best option for linux guitar by far, 12 Fender amps, and a nice box
of fx are modeled, its just too easy :wink:

http://www.linuxjournal.com/content/plu ... er-mustang

http://www.youtube.com/watch?v=Wl2Q8SNVnPU

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whippet6 wrote:Thank you very much. I thought my internal sound card should handle it via the mic input (I have no line in on my laptop). But I suspect that the guitar pickups did not put out enough power which is what you pointed out. I'll have to get the guitar/ USB connection from Musician Friend. Again, thanks for your time and help.
In the meantime, that input might be switchable between input
levels. Look in the docs or google.

Also, Radioshack probably has 1/4" to rca adaptors, with a variety of
cable,adaptor combos
to achieve the end result of pre-amping the guitar with an
existing home stereo, using the standard aux option, and rca in/out jacks
and 1/8" adaptor to connect to the laptop
as well as enable some basic EQ settings. Some good old receivers are at the
Goodwill/Salvation Army type stores for $20-$40 on good days.

Even a quality old Cassette recorder with i/o jacks could preamp your signal.
Plugins are even created for that nice analog sound!
Cheers

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