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wiki:cadence_introduction [2013/10/22 15:33] – [JACK Status] danboidwiki:cadence_introduction [2013/10/22 15:48] (current) – [JACK Bridges] danboid
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 **Xruns** For JACK to operate smoothly and without drop-outs it requires that its buffers (the memory used to transport audio) provide a continuous stream of data. Whenever this data fails to arrive in time to satisfy the requests of a JACK app it causes an xrun which is often accompanied by a disruption to the sound output. The key to success with JACK is to eliminate (or at least minimize) xruns. **Xruns** For JACK to operate smoothly and without drop-outs it requires that its buffers (the memory used to transport audio) provide a continuous stream of data. Whenever this data fails to arrive in time to satisfy the requests of a JACK app it causes an xrun which is often accompanied by a disruption to the sound output. The key to success with JACK is to eliminate (or at least minimize) xruns.
  
-**Buffer** size is measured in frames per second. It determines the latency between the audio being received by JACK and being sent to the output device. The smaller the buffer the lower the latency and, as a result, the higher the accuracy when monitoring audio for multitrack recording. 1024 is the default and is usually a safe value but smaller buffer sizes have less latency, i.e. less delay between the input and output. Try different settings to see how low you can go when recording without getting xruns. The functioning of lower size buffers depends on the power of your CPU and the specifics of your audio device. The lowest buffer most devices can handle well is 64.+**Buffer** size is measured in frames per second. It determines the latency between the audio being received by JACK and being sent to the output device. The smaller the buffer the lower the latency and, as a result, the higher the accuracy when monitoring audio for multitrack recording. 1024 is the default and is usually a safe value but smaller buffer sizes have less latency, i.e. less delay between the input and output. Try different settings to see how low you can go when recording without getting xruns. The functioning of lower size buffers depends on the power of your CPU and the specifics of your audio device. The lowest buffer size most decent quality audio devices can handle well is 64.
  
-**Sample rate** is the frequency JACK will run and record audio at. 44.1kHz is the CD audio standard, but 48kHz is more common to go with video or for other typical audio. Higher sample rates allow for higher quality but take more disk space. Even for professional purposes, 48kHz is usually fine as the default.+**Sample rate** is the frequency JACK will run and record audio at. 44.1kHz is the CD audio standard, but 48kHz is more common to go with video or for other typical audio. Higher sample rates allow for higher quality but require more disk space. Even for professional purposes, 48kHz is usually fine as the default. Additionally, 48 and 96Khz allow for lower latency than using 44.1 or 88.2 due to the way it is calculated.
  
 **Latency** is the JACK capture latency which measures the time taken to fill the audio capture buffer. This value is determined by the buffer, period size and samplerate settings used to start JACK. **Latency** is the JACK capture latency which measures the time taken to fill the audio capture buffer. This value is determined by the buffer, period size and samplerate settings used to start JACK.
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 =====JACK Bridges===== =====JACK Bridges=====
  
-Cadences main window integrates the control of a few 'JACK bridges' -services which enable alternate Linux sound systems to run seemlessly atop JACK.+Cadence's main window integrates the control of a few 'JACK bridges' -services which enable alternate Linux sound systems to run seemlessly atop JACK.
  
 The ALSA audio bridge enables one or more ALSA audio applications to access your JACK device when it is started. Most everybody will want to ensure this is kept running alongside JACK as it enables audio for non-JACK apps such as Firefox. If you have chosen for JACK to start at boot then the ALSA audio bridge also gets started automatically. The ALSA audio bridge enables one or more ALSA audio applications to access your JACK device when it is started. Most everybody will want to ensure this is kept running alongside JACK as it enables audio for non-JACK apps such as Firefox. If you have chosen for JACK to start at boot then the ALSA audio bridge also gets started automatically.
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 The ALSA MIDI bridge needs to be running if you want to use any MIDI hardware. The ALSA MIDI bridge needs to be running if you want to use any MIDI hardware.
  
-PulseAudio is not included by default with KXStudio, and so the PulseAudio bridge will not function without PulseAudio.. Most applications which use PA also use ALSA directly so there is then no need for PA or the bridge. If needed for some reason, you can use PA with JACK via the bridge if PulseAudio is installed first.+PulseAudio is not included by default with KXStudio and the PulseAudio bridge will not function until it has been installed. Most applications which use PA can use ALSA or JACK instead so there is often no need for PA and its bridge.
wiki/cadence_introduction.1382448793.txt.gz · Last modified: 2013/10/22 15:33 by danboid