Index: jack.xml
===================================================================
--- jack.xml (revision 4434)
+++ jack.xml (working copy)
@@ -10,10 +10,183 @@
Before you can begin to use Ardour, you will need to get the audio
input/output capabilities of your system working and properly
configured. There are two aspects to this process: getting your audio
- interface (soundcard) working, and configuring it to work with the Jack
+ interface (sound card) working, and configuring it to work with the Jack
Audio Connection Kit (JACK).
+
+ Quickstart
+
+ To get audio in and out of your Computer, you need to run a piece of
+ software called JACK, which you can imagine as cables in a real studio.
+ Fortunately, Ardour can start JACK for you and then communicate with it
+ to connect to your sound card or to other software.
+
+
+
+ When starting Ardour, the "Session Control" window is shown and you
+ are asked to create a session or load an existing one. If JACK is
+ not running, the tab Audio Setup will appear.
+ If jack is already running (e.g. if you started it with
+ qjackctl), the tab will not show up;
+ skip to point 3 in that case.
+
+
+
+
+ In the Audio Setup tab you may change the
+ settings. However, the defaults should be ok.
+
+
+
+
+ Create a session or open an existing one (as described in ) and begin using Ardour! If you
+ encounter problems, e.g. if you are not able to hear something or
+ to record sound from your sound card, come back to this chapter and
+ read further.
+
+
+
+
+
+
+
+ Getting Your Audio Interface Working
+
+
+ Although Ardour runs on OS X as well as Linux, this section
+ describes only a Linux system. The issues faced on OS X tend
+ to be entirely different.
+
+
+
+
+ Getting your audio interface (sound card) working can be the hardest part
+ of setting your computer up to run Ardour, or it could be one of the
+ easiest. The level of difficulty you will face depends on the type of
+ audio interface ("sound card") you are using, the operating system
+ version you are using, and your own understanding of how it all works.
+
+
+
+ In general, your sound card has to be supported by Linux. You can check
+ the Alsa
+ soundcard matrix for which hardware is supported. Other
+ hardware may be supported by FFADO which is
+ a collection of drivers for FireWire connected devices. You can check
+ whether your sound card works by playing a CD, MP3 or whatever.
+ Getting the hardware running is not in the scope of the Ardour manual.
+
+
+
+ Selecting Capture Source
+
+ If your soundcard is working, you need to select the correct capture
+ source. Many audio interfaces, particularly the cheaper varieties that
+ are often found built into computers, have ways to plug in both
+ microphones and instruments or other audio equipment to be recorded.
+ This immediately poses a question: how does Ardour (or any software)
+ know which signal to record, the one coming into the microphone input,
+ or the one arriving at the "line in" socket? The same question arises
+ also for "high-end" audio interfaces, though in different ways.
+
+
+
+ The short answer is: Ardour doesn’t. Instead, this is a choice you
+ have to make using a program that understands how to control
+ the mixing hardware on the audio interface. Linux/ALSA has a number of
+ such programs: gnome-volume-control, kmix, gamix, aumix and alsamixer
+ are just a few of them. Each of them offers you a way to select which
+ of the possible recordable signals will be used for as the "capture
+ source". They also offer to adjust the level of the capture source
+ signal. How to select the preferred signal and its level varies from
+ program to program, so you will have to consult the help documentation
+ for whichever program you choose to use.
+
+
+
+ There are also a few programs that offer ways to control just one
+ particular kind of audio interface. For example, the
+ hdspmixer program offers control over the
+ very powerful matrix mixer present on several RME audio interfaces.
+ envy24ctrl does the same for a number of
+ interfaces built around the common ice1712/envy24 chipset, found in
+ devices from M-Audio, Terratec and others. Please note that this is
+ quite similar to the situation for Windows and MacOS users, where each
+ audio interface often comes with its own control program that allows
+ certain critical configuration choices to be made.
+
+
+
+
+
+
+ Can I use multiple sound cards?
+
+ It is no problem with having multiple sound cards built-in into your
+ computer, but for Ardour (more precisely: for JACK) you have to choose
+ which one to use. It is not possible to increase the number of hardware
+ audio channels by combining sound cards, and there are good technical
+ reasons why this will not be implemented in future. If you need more
+ channels, save your money for a while and buy yourself a properly
+ designed multichannel sound card.
+
+
+
+
+
+
JACK
@@ -43,173 +216,319 @@
of sample synchronisation you’d have in a properly configured
digital hardware system. This is a problem that has been solved at
least a couple of times (ReWire from PropellerHeads and DirectConnect
- from Digidesign are the two most common examples), but JACK is a new
+ from Digidesign are the two most common examples), and JACK is a new
design developed as an open source software project, and is thusly
- available for anyone to use, learn from, extend, *fix or modify.
+ available for anyone to use, learn from, extend, fix or modify.
+
-
- Getting Your Audio Interface Working
-
-
- Although Ardour runs on OS X as well as Linux, this documentation
- describes only a Linux (ALSA) system. The issues faced on OS X tend
- to be entirely different, and are centered mostly on JACK. There are
- also alternative audio device driver families for Linux but they are
- also not discussed here.
-
-
-
- Getting your audio interface working can be the hardest part of
- setting your computer up to run Ardour, or it could be one of the
- easiest. The level of difficulty you will face depends on the type of
- audio interface ("soundcard") you are using, the operating system
- version you are using, and your own understanding of how it all works.
+ JACK itself does not come with graphical user interface, it runs
+ entirely in the background and is used by so-called "clients", e.g. by
+ Ardour. The clients connect to JACK and can then ask which other
+ clients are present (i.e. connected to JACK) and which inputs and
+ outputs they have. The clients can then connect to each other, using
+ JACK.
- In an ideal world, your computer already has a working audio
- interface, and all you need do is to start up qjackctl and run JACK.
- You can determine if you face this ideal situation by doing a few
- simple tests on your machine. The most obvious test is whether
- you’ve already heard audio coming out of your computer. If you are
- in this situation, you can skip ahead to
- .
+ Ardour offers possibilities to connect its inputs and outputs to other
+ clients (or to its own inputs and outputs) or to the audio hardware, i.e.
+ your sound card. Another useful software is
+ qjackctl, which is also a JACK client and
+ allows to connect other clients to each other, see their actual
+ connections and even re-connect them automatically next time they are
+ started.
-
-
- Checking For an Audio Interface
- If you’ve never tried to play audio on your computer before, you
- should use a basic playback program such as play, aplay or possibly
- xmms. Find an audio file on your machine (locate
- .wav may help here), and try to play it. There are several
- possibilities:
+ To use JACK it must be started firstly. You can use
+ qjackctl to start/stop JACK, which is quite
+ convenient. Another way is using Ardour to start JACK, or you can start
+ JACK yourself on a console, using the command
+ jackd, which has no graphical user interface.
-
-
-
- You may get an error from the program
-
-
+
+ Controlling JACK using Qjackctl
+
+ You should be able to start qjackctl from the “application menu”
+ of your system, typically found on the panel/appbar/dock or whatever
+ its called that lives at the top/bottom/left/right of your screen.
+
-
-
- You may hear nothing
-
-
+
+ In the qjackctl window click
+ Start to start JACK. You can configure the
+ parameters in the preferences dialog, which you get by clicking
+ Setup. Most of the settings require restart of
+ JACK by first clicking Stop, then
+ Start.
+
-
-
- You may hear something, but its too quiet
-
-
+
+ You may see and modify the actual connections of the JACK clients in
+ the "Connections" window. You can show this window by clicking
+ Connect. Right after starting JACK, no clients
+ are connected, of course.
+
-
+
+ If you stop JACK, the connections you made in the last session are
+ lost. The JACK clients may choose to remember them and to reconnect
+ when JACK is started again. Ardour does not (at least not for all
+ connections), but you can configure qjackctl
+ to do so by using the Patchbay feature.
+
+
+
+ Click on the Patchbay button, then click on
+ New. Qjackctl will ask if you want to
+ create a patchbay definition as a snapshot of all actual client
+ connections. Clicking on Yes will bring in
+ a set of all ports available. Note that changes which you make here
+ will not change your actual connections.
+
+
+
+
+
+
+
+
+
+ Make sure you've got the connections you want to be restored in the
+ future and click Save... and choose a filename.
+ Once this is saved, you can close the Patchbay.
+
+
+
+ Note
- you may hear something from the wrong loudspeakers.
+ Changes you make to your connections after saving the Patchbay will
+ not be in the Patchbay and thus not restored in future. You can
+ create a new Patchbay file, overwriting the old one.
-
-
-
+
-
- Selecting Capture Source
-
- Many audio interfaces, particularly the cheaper varieties that are
- often found built into computers, have ways to plug in both
- microphones and instruments or other audio equipment to be recorded.
- This immediately poses a question: how does Ardour (or any software)
- know which signal to record, the one coming into the microphone input,
- or the one arriving at the "line in" socket? The same question arises
- also for "high-end" audio interfaces, though in different ways.
-
+
+ Next, click on the qjackctl Setup button,
+ then click on the Options tab.
+
-
- The short answer is: Ardour doesn’t. Instead, this is a choice you
- have to make using a program a program that understands how to control
- the mixing hardware on the audio interface. Linux/ALSA has a number of
- such programs: alsamixer, gamix, aumix, kmix are just a few of them.
- Each of them offers you a way to select which of the possible
- recordable signals will be used for as the "capture source". How you
- select the preferred signal varies from program to program, so you
- will have to consult the help documentation for whichever program you
- choose to use.
-
+
+
+
+
+
-
- There are also a few programs that offer ways to control just one
- particular kind of audio interface. For example, the
- hdspmixer program offers control over the
- very powerful matrix mixer present on several RME audio interface.
- envy24ctrl does the same for a number of
- interfaces built around the common ice1712/envy24 chipset, found in
- devices from M-Audio, Terratec and others. Please note that this quite
- similar to the situation for Windows and MacOS users, where each audio
- interface often comes with its own control program that allows certain
- critical configuration choices to be made.
-
-
-
-
-
- the wrong capture source selected in the audio interface’s
- hardware mixer (see above)
-
-
+
+ Starting JACK using Ardour
+
+ You can also use Ardour to start JACK. You will get less flexibility
+ (e.g. no Patchbay), but setup is easier and faster, which is good for
+ an ad-hoc session.
+
-
-
- the "capture" gain level in the audio interface’s hardware
- mixer is turned down too low. You will need to use a hardware
- mixer application (as described above) to increase this.
-
-
-
+
+ Start Ardour as usual. You will get the "Session Control" window. If
+ JACK was not started yet, the tab Audio Setup will
+ be visible. Click on it and make your choices. The defaults should
+ work for you, but you may choose to change them. Then go to the
+ New Session or Open Session
+ tab to begin a session as usual (see for
+ details).
+
+ Note
- You will notice in the mixer strip for each track in ardour that
- you can change the selection of the monitoring source between
- input/pre/post. Adjusting the fader while watching the ’input’
- levels will NOT have any affect on the levels. As mentioned above,
- ardour is dependent on external mixer settings for a source level.
+ When Ardour exits, it detects whether other clients (e.g. qjackctl,
+ jamin) are still connected to JACK and if not, it will stop JACK.
+ Thus, if you use Ardour as sole JACK client, it will start jack at
+ the beginning of your session and stop it at the end.
+
+
+ The following sections will provide detailed information about the
+ options found in the Audio Setup tab.
+
+
+
+ Note
+
+ Not all combination of parameters are meaningful or will even work.
+ You have to know what you are doing for taking full advantage of all
+ possibilities.
+
+
+
+
+
+ The Device tab
+
+ In the tab Device you may choose the driver and
+ tweak some basic parameters.
+
+
+
+
+ Driver
+
+
+ Here you can choose the driver to use. In most cases you will
+ choose ALSA to connect JACK to your sound
+ card. If your system uses OSS instead of ALSA, choose
+ OSS. If you have a FireWire sound card,
+ try FFADO. The driver
+ NETJACK connects to a running JACK on
+ another computer which is reachable by a fast network
+ connection. This way, it is possible to connect ardour to
+ applications and sound cards on another computer. The
+ Dummy driver connects JACK to no hardware,
+ so only audio data transfer between applications will be
+ possible.
+
+
+
+ Interface
+
+
+ Depending on the chosen driver you can choose the appropriate
+ Interface here, i.e. which sound card to use. If the field is
+ not meaningful (e.g. for the Dummy driver) it is disabled.
+
+
+
+ Sample Rate
+
+
+ You can choose the appropriate sample rate here. Typical values
+ are 48000Hz or 441000Hz.
+
+
+
+ Buffer Size
+
+
+ This is a technical parameter affecting operation of the sound
+ card. Smaller values lead to smaller latency, but too small
+ values lead to bad-sounding artefacts.
+
+
+
+ Number of buffers
+
+
+ This is also a technical parameter affecting operation of the
+ sound card. Smaller values lead to smaller latency, but too
+ small values lead to bad-sounding artefacts.
+
+
+
+ Audio Mode
+
+
+ You can choose whether your sound card can be used to playback
+ (output sound), record (input sound) or both. If you choose
+ Playback/Recording on 1 Device, the same
+ audio device (i.e. sound card "subdevice") is used for both
+ input and output. If you choose Playback/Recording on
+ 2 Devices, different audio devices can be used for
+ input and output. The devices can be chosen in the
+ Advanced tab, but must be part of the same
+ interface (sound card).
+
+
+
+
+
+
+
+ The Options tab
+
+ In the tab Options you have additional control
+ about how JACK runs. These options are specific to JACK and will
+ therefore not be documented here. For further information see the
+ manpage of jackd (open a terminal/console
+ and type man jackd, then press enter).
+
+
+
+
+ The Advanced tab
+
+ In the Advanced tab you have advanced control
+ about your sound card configuration.
+
+
+
+ Input device
+
+
+ Here you can choose which device you want to use to get sound
+ into your computer. The function of this field depends on the
+ chosen driver and Audio Mode.
+
+
+
+ Output device
+
+
+ Here you can choose which device you want to use to get sound out
+ from your computer. The function of this field depends on the
+ chosen driver and Audio Mode.
+
+
+
+ Input channels
+
+
+ TBD
+
+
+
+ Output channels
+
+
+ TBD
+
+
+
+ Hardware input latency
+
+
+ TBD
+
+
+
+ Hardware output latency
+
+
+ TBD
+
+
+
+
+
@@ -217,11 +536,11 @@
Monitoring Choices
Its unfortunate that we have to raise this issue at a point in the
- manual where you, the reader, may not even knoiw what "monitoring"
+ manual where you, the reader, may not even know what "monitoring"
means. However, it is such an absolutely critical aspect of using any
digital audio workstation that we need to at least cover the basics
here. The only people who don’t need to care about monitoring are
- those who will never use ardour to record a live performance (even on
+ those who will never use ardour to record a live performance (even
performed using a software synthesizer).
@@ -237,7 +556,7 @@
amp+loudspeakers? It can get a lot more complex than that: if you are
recording multiple performers at the same time, each performer needs
to hear their own playing/singing, but they also probably need to hear
- some of their colleagues’ sound as well. You might be overdubbing
+ some of their colleagues’ sound as well. Or you might be overdubbing
yourself - playing a new line on an instrument while listening to
tracks you’ve already recorded - how do you hear the new material as
well as the existing stuff?
@@ -250,41 +569,7 @@
-
- Can I use multiple soundcards
-
- There are really lots of great reasons why you should not even attempt
- to do this. But seriously, save your money for a while and buy
- yourself a properly designed multichannel soundcard.
-
-
-
- Qjackctl
-
- JACK itself does not come with graphical user interface - to start
- JACK and control it you need to have access to a command line and a
- basic knowledge of Unix-like operating systems. However,
- qjackctl is a
- wonderful application that wraps JACK up with a graphical interface
- that is both nice to look at and useful at same time. qjackctl is the
- recommended way of using JACK.
-
-
-
-
-
-
-
- You should be able to start qjackctl from the “application menu”
- of your system, typically found on the panel/appbar/dock or whatever
- its called that lives at the top/bottom/left/right of your screen.
-
-
-
- [ need screenshot of GNOME/KDE/OSX menus here ]
-
-