Reverse detail from Kakelbont MS 1, a fifteenth-century French Psalter. This image is in the public domain. Daniel Paul O'Donnell

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Linux/Chrome on Chromebook using Crouton

Posted: Jun 04, 2017 12:06;
Last Modified: Jun 04, 2017 12:06

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There are many articles about this on the web. This is just a reminder to me as to what I’ve been doing.

Change boot to developer mode

Doing the following deletes all local data on your system. You can always reinstall the Operating System (Chrome seems to do that remotely). But your data is wiped after you do this.

Download Crouton

Open a terminal

Install Crouton

The following installs to an encrypted partition a minimal version of the latest version of the Ubuntu LTS with the xfce and unity and the “Extension” utility that allows you to use a common clipboard between Chrome OS and Ubuntu.

Here are some help options

Run Crouton

After you’ve installed the versions you want, you start your Linux session by

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Installing Vidyo on Ubuntu 16.10

Posted: May 12, 2017 15:05;
Last Modified: May 14, 2017 14:05

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I need to use Vidyo conferencing software for some projects I’m on. Because I just reinstalled Ubuntu 16.04, I needed to reinstall the Vidyo desktop.

This is not easy, since the installation file Vidyo directs you to contains a dependency that is not available on Ubuntu 16.10 (libqt4-gui).

There are various solutions out there, though I was not able to get the one proposed by Vidyo itself to work.

The one that did work for me is on the CERN site.

apt-get -f install
sudo apt-get install libqt4-designer libqt4-opengl libqt4-svg libqtwebkit4
wget -O vidyo-desktop.deb https://goo.gl/2Ykmoq
sudo dpkg -i vidyo-desktop.deb
apt-get -f install

To run Vidyo, either type VidyoDesktop at the command line or use the HUD to find VidyoDesktop in your GUI.

Notes

  1. The apt-get -f install is not really necessary if you do this first. I did it (as does the original poster) in order to clean up mistakes I made earlier.
  2. Instead of wget -O vidyo-desktop.deb https://goo.gl/2Ykmoq you can download the file in your webbrowser (the google short URL resolves to a Dropbox file: https://www.dropbox.com/s/7cw6acxm4ys2ioy/VidyoDesktopInstaller-ubuntu64-TAG_VD_3_6_3_017-no_libqt4-gui.deb?dl=0); if you do this, then you need to use that longer filename in the rest of the commands.
  3. libqt4-designer libqt4-opengl libqt4-svg are dependencies that were originally unmet when I tried installing Vidyo. The person who posted this solution also added libqtwebkit4 so I did too. I’m not sure it is necessary, however.
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Displaylink and Ubuntu 16.10 and 17.04

Posted: May 11, 2017 14:05;
Last Modified: May 11, 2017 14:05

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I have a new supercool three screen setup in my office.

To run this, I am using two cables: A old-style displayport cable to the middle screen, and HDMI cables, via a Dell USB3 Docking station, to the side screens.

Running screens via a USB docking station requires me to use DisplayLink. Fortunately, Displaylink have an Ubuntu driver. Unfortunately, this doesn’t seem to work with 17.04 and getting it to work well with 16.10 LTS requires a little fiddling. The rest of this post is about that.

Contents

General requirements (16.10 LTS)

The first thing is general requirements.

You need to install two things in order to run the driver:

  1. Download the Ubuntu driver from here: “http://www.displaylink.com/downloads/ubuntu” (this is a zipped archive)
  2. Open a terminal and install dkms
    sudo apt-get install dkms
  3. Extract the displaylink .run file from the Zip file you downloaded in (1)
  4. Navigate in the terminal to the directory in which you expanded the zip file and run the following command:
    sudo ./displaylink-driver-n.n.nn.run (where “n.n.nn” is your version number)

At this point, in 16.10 LTS, the driver should be working and you should be able to use your docking station.

Arranging the Screens (16.10 LTS).

Once the driver is installed and your docking station is connected, you will want to arrange your screens. At least in my case, the standard arrangement is that all three screens were placed on top of each other in space (meaning that they reflect the same area in the display space). It was also the case that my middle screen was not rotated 180° Clockwise, as I need it.

There is a graphic interface for doing this (System Settings>Screen Display). But the actual screens are hard to get in place (there seem to be hidden constraints on their movement). What I found after much trial and error was that it is best to work with two screens at a time. I.e. turn off all but your main screen (in my case the 30” oriented clockwise) and one of the other screens. Once you have those two in place, “Apply” and accept the settings. Then move the second screen to as close to where you want it as possible and turn it on as well. Then “Apply” and accept the settings. Then finally do any minor adjustments.

Ubuntu 17.04 doesn’t seem to work

As far as I can tell, the DisplayLink drivers simply do not work with 17.10. I read somewhere that all DisplayLink hardware reports on the hex location 17e9, so if you run lsusb -d 17e9 you should see your hardware if it is working. Unfortunately I couldn’t see anything in 17.04. And I simply could not get my side screens to show anything via the dock.

Other issues

Originally I was using DisplayLink with a 16.10 system that had been upgraded multiple times (probably from a clean-install of 15.04 or 15.10). I found that it threw a lot of errors. I’m now running it on a clean install from 16.10 LTS and it hasn’t thrown any.

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Fixing QJackCtl

Posted: Aug 16, 2015 12:08;
Last Modified: Aug 16, 2015 12:08

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A really brief note on how to fix a problem with qjackctl not starting jackd. If you don’t understand this, then it isn’t relevant for you.

Contents

The problem: QJackCtl can’t start the JACK server

Was having trouble with QJackctl (a daemon for running Jack, connection software required for media production software within Ubuntu):

1) D-BUS: JACK server could not be started. Sorry
2) Could not connect to JACK server as client. - Overall operation failed. - Unable to connect to server. Please check the messages window for more info.

Screenshots of the error


Output of message

12:14:54.591 Patchbay deactivated.
12:14:54.593 Statistics reset.
12:14:54.598 ALSA connection change.
12:14:54.606 D-BUS: Service is available (org.jackaudio.service aka jackdbus).
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
12:14:54.614 ALSA connection graph change.
12:14:57.883 D-BUS: JACK server could not be started. Sorry
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
Sun Aug 16 12:14:57 2015: Starting jack server...
Sun Aug 16 12:14:57 2015: JACK server starting in realtime mode with priority 10
Sun Aug 16 12:14:57 2015: self-connect-mode is "Don't restrict self connect requests"
Sun Aug 16 12:14:57 2015: ERROR: cannot register object path "/org/freedesktop/ReserveDevice1/Audio0": A handler is already registered for /org/freedesktop/ReserveDevice1/Audio0
Sun Aug 16 12:14:57 2015: ERROR: Failed to acquire device name : Audio0 error : A handler is already registered for /org/freedesktop/ReserveDevice1/Audio0
Sun Aug 16 12:14:57 2015: ERROR: Audio device hw:0 cannot be acquired...
Sun Aug 16 12:14:57 2015: ERROR: Cannot initialize driver
Sun Aug 16 12:14:57 2015: ERROR: JackServer::Open failed with -1
Sun Aug 16 12:14:57 2015: ERROR: Failed to open server
Sun Aug 16 12:14:59 2015: Saving settings to "/home/dan/.config/jack/conf.xml" ...
12:15:17.033 Could not connect to JACK server as client. - Overall operation failed. - Unable to connect to server. Please check the messages window for more info.
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started

The solution

The first of these error messages is widely reported and seems to cause a ton of trouble. Suggestions includie klilling pulseaudio and restarting things; making sure you’ve been added to the audio user group; making sure that there is an audio group (i.e. that JACK has access to a real time kernel. Here are some sites I visited that deal with common issues involving this error, none of which were the actual problem for me, though they have useful advice on things to look for):

In my case, the problem turned out to be simply an issue in the qjackctl settings. I needed to explicitly say which sound card it was to use, as indicated telegraphically here: http://ubuntuforums.org/showthread.php?t=2238377&p=13093181#post13093181

How to fix the settings:

1) In a terminal start qjackctl: > qjackctl

2) Before you try to start it, click the “setup” button in the GUI (right hand side, middle).

3) On the setup GUI change “Input Device” and “Output Device” (middle, right hand side) from “(Default)” to “HW:PCH” (In the screenshot one has been changed and the other not).

4) Restart qJackCtl. You should now be able to successfully use the “Start” button.

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Problems with Cisco Anyconnect on Ubuntu 14.04 (Breaks Internet Connections)

Posted: Jan 11, 2015 22:01;
Last Modified: Jan 11, 2015 22:01

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This blog is about resolving an issue I had after installing Cisco Anyconnect, the U of L’s VPN client.

This is an aide memoire for me, but might be useful to others. The information comes from, with the first being most useful for this particular case:

Contents

The symptoms

The U of L uses Cisco Anyconnect as its VPN client. I installed it two days ago (stupidly, while travelling). This produced a problem where I couldn’t access the internet: I could log in to a SSD, but couldn’t ping any sites, and none of my webbrowesers could resolve or connect to any hosts.

#h3(#diagnosis). The diagnosis

The problem is that anyconnect rewrites /etc/resolv.conf.

The original /etc/resolv.conf is a link to /run/resolv.conf/ and /run/resolvconf/resolv.conf@ contains a local address nameserver (in my case 127.0.1.1, others report 127.0.0.1).

Anyconnect backs this file up (whew!) as /etc/resolv.conf.vpnbackup and replaces it with a new resolv.conf that contains a number of different nameservers in the uleth domain (i.e. 142....).

The solution

Things that don’t work

These are the things I tried that don’t work (in the order I tried them).

What works

Because anyconnect backs things up, all you need to do is the following:

  1. cd to /etc/
  2. check that the situation matches what I’m reporting (i.e. that there are two resolv.conf files, resolv.conf and resolv.conf.backupvpn or similar.
  3. rename the current resolv.conf: mv resolv.conf resolv.conf.CISCO
  4. rename the current resolv.conf.backupvpn (or similar): mv resolv.conf.backupvpn resolv.conf
  5. check that the (now) current resolv.conf is a link to /run/resolvconf/resolv.conf by running ls -l resolv.conf on /etc/ (if it is a link, the line will include an arrow showing what it is pointing at).
  6. check that the nameserver in resolv.conf is a local address (127...).
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Mounting University of Lethbridge "P," "R," and "W" drives under Linux

Posted: Feb 19, 2014 14:02;
Last Modified: Jul 20, 2016 16:07

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Here’s how to mount “P” (Personal), “R” (shared research), “W” (web), and department/committee drives at the University of Lethbridge.

Contents

“P” drives

Your “P” drive is the windows share that represents your standard network desktop (i.e. the thing you see if you log into a classroom or other computer on campus).

The address is ulhome.uleth.ca/$USER where $USER is your account username (the same as the lefthand side of your uleth email account, or, in my case, daniel.odonnell.

ulhome is a CIFS drive. To mount it, you seem to have to use the commandline (I can’t seem to find the right protocol to use to use the GUI that comes with the file navigator in Ubuntu. I found instructions that worked for me here: http://www.tonido.com/support/display/cloud/Howto+properly+mount+a+CIFS+share+on+Linux+for+FileCloud

And, to solve the permissions problem that first arose, http://ubuntuforums.org/showthread.php?t=1409720

One-time mount

To mount the drive by hand for a single session, do the following:

  1. Make sure cifs-utils is installed
  2. Choose a mount point. This can be an existing directory (if the directory has local content, it will not be available while the network drive is mounted). Or you can create a custom mount point. I did the latter: mkdir ~/ulhome
  3. Mount the remote drive. sudo mount -t cifs -o username=$USER,password=$PWORD,rw,nounix,iocharset=utf8,file_mode=0777,dir_mode=0777 //$REMOTEURL $MOUNTPOINT (where $USER = username; $PWORD = password; $REMOTEURL = url of CIFS drive; and $MOUNTPOINT = the directory you chose or created in step 2. Note: your IT department may not give you the full remote URL, since Windows can use the first part of the subdomain; at the U of L, for example, IT tell you the share is called \\ULHOME. I guessed it is probably in the University’s main domain and was correct: \\ULHOME is the same as //ulhome.uleth.ca/)

Automount

To permanently mount the drive you need to create a password file and use that in /etc/fstab:

1. Create a file /root/.smbcredentials with the following content:

username=$USER
    password=$PWORD

p.2. Change the permissions such that only root can read the file.
sudo chmod 700 /root/.smbcredentials

3. Now add the following line in /etc/fstab file.

//$REMOTEURL $MOUNTPOINT cifs default,uid=1000,gid=1000,credentials=/root/.smbcredentials,rw,nounix,iocharset=utf8,file_mode=0777,dir_mode=0777 0 0

nb: the default,uid=1000,gid=1000 part comes from http://ubuntuforums.org/showthread.php?t=1409720 This is to answer the problem of them mounting RO. When I tried this out, I then had to go into the directory on my local machine and manually change the permissions from access only to read and create.

4. Test if the line added in the fstab file works.

# sudo mount -a

5. Now the remote share should be mounted at /mnt/storage.

Your “R” drive

The “R” or research drive is a shared drive you can use for collaborative research projects. It is found at uleth.ca/research/$DRIVENAME where $DRIVENAME is the name IT gives the space (e.g. genee_students).

You access this using smb (Microsoft’s workgroup protocol)

  1. In Nautilus, choose “Connect to Server”
  2. In the dialogue that pops up enter the network name, prefixed by the smb protocol (smb://uleth.ca/research/$DRIVENAME).
  3. In the authentication dialogue, your username is your (full) uleth email address; password is the same as your uleth network password.
  4. That’s it.

Your “W” drive

The “W” or public drive (the drive your web files are on) is found at files.uleth.ca. This can be ssh’d into and so is a lot easier to use.

ssh $USER@files.uleth.ca

Department and committee drives

A third kind of drive is department and committee drives. These are often made by IT with spaces in the name (grrr). An example might be: cifs://uldept.uleth.ca/ResearchServices/BoGRC Committee

There are different ways of handling spaces in file names depending on how you are mounting things. For use from the commandline for one-off mounting, several normal options (e.g. \ , \040, and %20) don’t seem to work. What does seem to work is putting the whole directory with the space in quotation marks. So in the above example, the following works (where $USER is your uleth username) : sudo mount.cifs //uldept.uleth.ca/ResearchServices/"BoGRC Committee" BOG -o username=$USER

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MySQL cheatsheet

Posted: Aug 27, 2012 13:08;
Last Modified: Aug 27, 2012 14:08

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From http://www.patrickpatoray.com/?Page=30

MySQL Dump/Restore

Dump ALL MySQL Databases

mysqldump —user=XXXXXXXX —password=XXXXXXX -A > /PATH/TO/DUMPFILE.SQL

Dump Individual or Multiple MySQL Databases

mysqldump —user=XXXXXXXX —password=XXXXXXX —databases DB_NAME1 DB_NAME2 DB_NAME3 > /PATH/TO/DUMPFILE.SQL

Dump only certain tables from a MySQL Database

mysqldump —user=XXXXXXXX —password=XXXXXXXX —databases DB_NAME —tables TABLE_NAME > /PATH/TO/DUMPFILE.SQL

Restoring dbase

  1. Use the following procedure to reload the contents of a database:
  2. Unzip the backup file you wish to use.
  3. Open it up and pull out only the information that you will need.
  4. Save this text file.
  5. Use the following command to feed back in the contents of a text file:
mysql —verbose —user=XXXXXXXX —password=XXXXXXXX DB_NAME < /PATH/TO/DUMPFILE.SQL
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set date and time from commandzone

Posted: Nov 22, 2011 21:11;
Last Modified: Jun 07, 2012 13:06

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http://codeghar.wordpress.com/2007/12/06/manage-time-in-ubuntu-through-command-line/

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Using the M-Audio Audiophile USB Digital Audio Interface with Linux

Posted: Sep 07, 2008 10:09;
Last Modified: Nov 01, 2014 15:11

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This describes how to get the M-Audio Audiophile USB Digital Audio Interface working with Linux/ALSA. It has been updated (2014-11-01) to reflect recent discoveries and now seems to work well.

Contents

Introduction

Many of my courses deal with sounds of speech, and I am increasingly looking to supplement my course materials with additional digital video and audio material.

The University of Lethbridge, like most universities, I imagine, is well equipped with computer labs and IT personnel who are able to assist faculty and students with production of this kind of material. But I am looking for something that will allow me both to experiment without committing to the time involved for arranging studio and personnel time, and something that will allow me to respond quickly to opportunities that arise in the course of the year or moments of pedagogical inspiration. The University also has lots of computer labs, after all, but most faculty have a computer on their desk anyway.

Since I was an avid home recording hobbyist in my teens and twenties, I had most of the most useful hardware in a closet: a decent microphone (necessary), and a mixer and patchbay (optional, though not if you want to do quality-sounding work); and the various cables (RCA, ¼ inch, MIDI, etc.) that make things cheaper and easier to set up. My mixer and patchbay were refugees from an old 1980s Yamaha MM30/MT44 Multitrack home studio (see image). Any old mixer will probably do, and I imagine you might be able to get some cheap ones on the internet. Having a mixer makes life easier in the sense that you have more control over the volume, stereo position, and quality of the audio signal before it gets to the computer. Certainly to begin, however, you can work without one, plugging your microphone directly into the card that acts as an interface between you and your computers.

M-Audio Audiophile USB Digital Audio Interface

The one thing I needed, of course was a way of connecting my microphone and mixer to the computer. I was in a music store on the weekend looking for some supplies, and I found a cheap used M-Audio Audiophile USB Digital Audio Interface (DAI) for sale. While you can buy microphones, record and cassette players, and MIDI cables that all convert a single input directly to USB for recording, a more general DAI like the Audiophile USB allows you to do more. With this, I’ll be able to convert cassettes of accents I have for my class on World Englishes to audio form as well, for example. The M-Audio was an extremely popular DAI, so there are likely thousands of used ones floating around.

A quick search on my cell phone found a page that described how to get the interface working and suggested that it is reasonably well supported in Linux. So I took a flutter. When I got home, I installed the audio software from Ubuntu Studio (a full-featured home studio suite, that is, of course, free). And used some hobby time getting things set up. All in all, it took me about 5 hours, including writing up this description of what I did.

The M-Audio Audiophile USB works with Linux due to some heroic efforts by a couple of people, most particularly Thibault Le Meur, who wrote the kernel documentation. These people have ferreted out and developed patches for the various inconsistencies in the device’s use of the USB protocols. The instructions for getting it working, however, are not always that easy to follow, so I thought I’d collect what I found and write down what worked for me.

Process

Getting the M-Audio Audiophile USB to work with Linux involves two discrete steps:

A third step, which isn’t applicable to my current project, involves getting the MIDI (Musical Instrument Digital Interface) input to work with digital instruments like synthesizers and drum machines. Since I’m at the moment only interested in recording relatively high quality spoken work and analogue feeds from cassettes and records, I haven’t tried it to see if the discussion below gets the MIDI working as well.

Getting the M-Audio Audiophile USB recognised by ALSA

As the kernel documentation indicates, the M-Audio Audiophile USB works partially with current versions of ALSA right out of the box. If have the right modules installed (and you almost certainly do, as USB sound is something I suspect all distributions support), ALSA will recognise your device as soon as you plug it in and turn it on.

So if you have headphones plugged in and have set the card to be the choice for playback (either using whatever utility your desktop uses for letting you set Sound preferences [in Ubuntu: System > Preferences > Sound Preferences], or by giving the hardware address explicitly to a program via the command line or configuration utility), you will be able to hear audio files sent to it.

The problem, however, is that you won’t be able to record anything—or at least anything meaningful. Due to a technical problem, the details of which thankfully don’t have to concern us, audio inputs to the device are recorded as white noise by ALSA if you use the default setting (If you are interested in the problem or planning to do development using the M-Audio Audiophile USB, you can read about the details of the issue in the kernel documentation).

The solution, developed by Thibault Le Meur and others, and recorded in the kernel documentation, is to reload the ALSA USB module with some device specific instructions:

  1. Turn off your M-Audio Audiophile USB sound card
  2. At the command line, remove the usb module: sudo modprobe -r snd-usb-audio
  3. Reinsert the module with explicit information about Audiophile’s location and setup, e.g. sudo modprobe snd-usb-audio device_setup=0x01
    1. Note: I used to specify both the index value index=0 and a different device_setup =0x09, but I found that the index wasn’t necessary with only one USB and that 0×01 worked way better than 0×09—in fact it answers the questions about noisiness in the comments below.
    2. Note the different possibilities are:
      1. device_setup=0×01 (this is the one I use now)
        1. 16bits 48kHz mode with Di disabled
        2. Ai,Ao,Do can be used at the same time
        3. hw:1,0 is not available in capture mode
        4. hw:1,2 is not available
      2. device_setup=0×11
        1. 16bits 48kHz mode with Di enabled
        2. Ai,Ao,Di,Do can be used at the same time
        3. hw:1,0 is available in capture mode
        4. hw:1,2 is not available
      3. device_setup=0×09 (This is the one I originally recommended, but it creates a lot of background noise).
        1. 24bits 48kHz mode with Di disabled
        2. Ai,Ao,Do can be used at the same time
        3. hw:1,0 is not available in capture mode
        4. hw:1,2 is not available
      4. device_setup=0×19
        1. 24bits 48kHz mode with Di enabled
        2. 3 ports from {Ai,Ao,Di,Do} can be used at the same time
        3. hw:1,0 is available in capture mode and an active digital source must be connected to Di
        4. hw:1,2 is not available
      5. device_setup=0×0D or 0×10
        1. 24bits 96kHz mode
        2. Di is enabled by default for this mode but does not need to be connected to an active source
        3. Only 1 port from {Ai,Ao,Di,Do} can be used at the same time
        4. hw:1,0 is available in captured mode
        5. hw:1,2 is not available
  4. Turn your M-Audio Audiophile USB sound card back on.

You are now able to record and playback audio files. You can test it out by plugging a microphone into the one of the two ¼” (unbalanced) input plugs on the right hand side of the back and making a recording from the command line using arecord; if you have a mixer, plug your microphone(s) into the mixer and connect the mixer’s audio out/line out plug to the Audiophile’s RCA Input jacks (second from the right when you are looking at the back):

arecord -D hw:1,1 -c2 -d 10 -t raw -r48000 -fS24_3BE test.raw

(this command uses the following options: -D hw1:1,1, the likely hardware address of your Audiophile USB card; -c2, two-channel recording [required for this card]; -d 10 duration of recording in seconds [default is infinite and is stopped by sending a break signal to the program]; -t raw, a .raw file type; -r48000, sampling rate; -fS24_3BE, number and order of bits).

You can then use aplay to play the recording back

aplay -t raw -r48000 -fS24_3BE test.raw

(the above command will output to your default sound card [i.e. probably the one that drives your speakers]; if you want to hear it in the headphones through your Audiophile, add -D hw:1,0 to the command).

Getting the M-Audio Audiophile USB recognised by JACK

update: I’m not sure the following is necessary any more. I was able to record well within Audacity without going to this step.

Command line recording is not a particularly user-friendly way of working, though knowing how to do it has its uses. For daily work, we are going to want to get the sound card working with the many excellent studio programs available for Linux, all of which (or at least all the most serious of which) work with the connection utility JACK. The fact that your Audiophile is recognised by ALSA, unfortunately, doesn’t seem to mean that it is recognised by JACK (actually your card does seem to be recognised by JACK without modification if you use the default module settings for snd-usb-audio; but it seems no longer to be recognised automatically by JACK or by the GNOME sound preferences manager after you add the device-specific options.

To get it recognised by JACK, you need to modify the JACK settings. You do this using jackctl (also known as qjackctl). While you can work from the command line with jackctl, Ubuntu Studio comes with a graphic version (Applications > Sound & Video > JACK Control).

  1. Once JACK Control is open, choose the “Setup” button;
  2. In Setup click on > beside “Input Device”;
  3. Choose the device that matches the hw: address you used above with arecord: probably hw:1,1 USB Audio #1
  4. Close the setup and start (or restart if you had already started) JACK.

Open up another JACK device (e.g. Ardour, the sound recording program, or even Meterbridge, the sound meter), and see if you are getting an audio signal from your microphone through your Audiophile USB sound card. If things are working, the audio will be available from system/capture 1 or capture 2 (if you used a microphone directly) or system/capture 1 and capture 2 (if you used a mixer); if these inputs are connected to something in the “Connection” button on the Jack Control, you should be able to record audio. If they or JACK are not working, you may need to play with some settings. I found, for example, that I basically was unable to record anything at under 1024 frames/period, and I got the best results by setting the frames/period to its maximum value of 4096. Unfortunately, this brings with it the cost of a very high latency (the time between a signal being triggered and its reception at the computer end): 171 msec. Many people, in contrast, seem to be working with latencies of <10 or even <5 msecs.

Since others appear to be able to get reliable functioning with much lower frames/period (and lower latency), I assume I still need to play with the various JACK settings and perhaps even some of the hardware connections. For the specific type of projects I have in mind at the moment, however—making single voice, spoken word recordings of sounds and words for my classes and converting tapes and records I have used in classes in the past to digital format—I suspect this is a relatively minor issue. I would appreciate any tips, however!

Examples

My first examples, recorded with a good mike, the mixer mentioned above, but otherwise unprocessed and recorded with my computer fan roaring in the background are available here: http://people.uleth.ca/~daniel.odonnell/Teaching/english-3450a-the-pronunciation-of-old-english

Problems

In addition to the latency issues mentioned above, I’m aware of/suspect there may be some additional issues.

  1. I’m not sure how the Audiophile USB card, or the special device specific instructions required to set the module up for it will affect other USB sound cards I use, particularly the USB headset I use for audio conferencing.
  2. Setting the JACK input to the Audiophile USB card looks like it may disable your ability to use other inputs in Jack without changing things back: I did a quick test with Hydrogen (a drum machine), for example, and it looks like I need to change the input back to get it to record in Ardour (though I’m not 100% certain this is true, since none of my spoken word requirements—at the moment!—require a drum track or other instrumentation).
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