Archives 2022

Raspberry PI in displayless mode…

I recently got a question about if Z-LiveRec could be used on Raspberry PI but without a screen or monitor. (Headlessmode) The idea from the user was to be able to remote control Z-LiveRec running on Raspberry using a RealVNC terminal window (which is built in Raspberry)

So the challenge was to create a Raspberry PI to boot up, logging in to the pre-defined WI-FI network and create a remote server session which any device on the same WI-FI network could to attach to.

I liked the idea – so I had to try it out!

I first installed a Raspberry PI and also Z-LiveRec and got it working, using a hdmi screen attached. I have a post for this exactly how to make a nice Raspberian installation for Z-LiveRec in this linked post. I had both DL32S and XR18 built in WI-FI on my target list for these tests. I tried first to attach to the terminal session by using XR18s built in Wi-Fi network. I was of course able to attach to the network from my iPad running x-air and also from the Raspberry PI. (The multichannel recording handled by Z-LiveRec is going over USB to XR18)

But after many attempts trying run the VNC client on my iPad…it was totally impossible to get XR18S built Wi-Fi network to route/forward any other network information than just the X-Air network information – which have been said using port 10024. (It does not route/handle port number 5900 as VNC is using) – and you also have a limit on max 4 devices on the built in XR18 Wi-Fi. So the conclusion was if you want to use VNC against a Raspberry PI forget the XR18 internal wifi – it is not possible.

Ok, I changed to a external router and BAM!!! The VNC session showed up and worked immediately!

So was now able to start Z-LiveRec in a VNC session from my iPad.

I have made the same tests on my Mackie DL32S…and here the internal router forwards all ports – so on this mixer the internal Wi-Fi can be used – but is not recommended…always use an external router when out on gigs!

To create a system which will auto start a VNC Server Session, the following tasks needs to be done.

Edit the rc.local file by typing:

sudo nano /etc/rc.local

Insert the following line, just before the exit 0 line.

sudo -u pi vncserver -randr=1280x720

You can check if VNC Server is installed…by typing VNCSERVER. You will also see which IP address is used.


Note: You actually don’t need to enable VNC in the PI configuration hardware…the auto startup will take care about this. (If you also enable it in the configuration…dual VNC sessions will be created – eating more resources.

Now you can run the VNC Client on your iPad and attach to the Raspberry PI – 192.168.1.xx:1

The login screen in VNC on a ipad.

Check your username and password.

It normally takes about 30 seconds for the system to boot up.

If you have trouble with cannot currently show desktop messages…set the screen resolution to 1280×720 with sudo raspi-config command and choose display options.

Conclusion – you can indeed use a Raspberry PI in headless mode/black box – and run Z-LiveRec remotely from any network device that is supported by VNC. (You need to have done the homework with all settings for the mixer wifi…but after this – it will work just as good as with a touch display.

Z-LiveRec V2.25 launched!

V2.25 2022-04-18 – NEWS!

I must first confess that development always takes 4 times more than expected. But here you have a new fresh version of Z-LiveRec – The multitrack recorder for Raspberry PI! In this new version you will find many nice improvements and also some new nice tools and functions that will make Z-LiveRec to the Virtual Soundcheck Tool #1 for your digital mixer!

Have a look – and please check the new version out!

  • Feature to change the ”Quit” button to not only quit the application – but also added the function to able to completely shutdown the Raspberry PI OS. This features can be turned “on” in the License dialogue window and by checking the Quit Button option.
  • Added keyboard shortcuts ctrl + r(recording), p(playing), s(stop), x(quit app), (and F1, F2, F4 and F10 – see below)
  • Added more buffer sizes – smaller size 131072 and bigger sizes 4194304 – to try with if buffer overruns show up and when using slower USB Sticks.
  • Fixed so that sound files can be played/read from any sub directory. Recordings will still only be stored in the root of the selected storage device. (Except when exporting recordings)
  • Added a file split counter in the GUI when recording in *.wav type of files. (2 GB splits)
  • Virtual Soundcheck & Export tools – Added locators in the GUI. When in play mode – the new Virtual Soundcheck & Export tools shows up with some new buttons. Left & right locator will set play area of an existing recording. Pressing “Play” will replay the recording between the locators. Pressing “loop” will keep playing the selected area between the locators forever. (Keyboard shortcuts are also added to set left/right locator by pressing ctrl F1 and ctrl F10. Ctrl F2 will start playing between the locators. Ctrl F3 will turn on ”loop” replay – Ctrl F4 will turn off loop replay)
  • Virtual Soundcheck & Export tools – by pressing “export” when replaying sound files in locator mode – the selected area between the locators can be exported to a new wave file. (This can be done from any file format like *.wav, *.W64 or *.caf and these can be exported to *.wav format. The exports can be done to both to a single multitrack file or be split by channel to separate wav files. See button “Separate tracks”) This function is extremely useful when been recording a complete concert with 32 channels and you want to export a part, song to a new separate file. By splitting all channels to separate files – any DAW on the market can be used for post-production tasks.
  • Virtual Soundcheck & Export tools – when in main window – an export function is available to export a complete recording from any file format like *.wav, *.W64 or *.CAF to *.wav format – both to a single multitrack file or been split by track/channel to separate wav files. See button “Separate tracks”. Note – Free storage space is needed on the same drive as the original file.

Performance and bug fixes:

  • Added some performance tweaks and fixed some hangs ups bugs.
  • Memory management using a garbage collector function to clean up the system after playing/recording – reports and stats can be found in the logfile.
  • Logging of CPU version and OS version when recording/playing in the Z-LiveRec.log.
  • Fixed a bug when in touch mode when the USB devices were more than 3, all devices did not report. Same with storage devices.
  • Hard test of doing large recordings – up to 64GB – without any problems or GUI shutdowns. Works great in Raspberry PI OS – 32bit Bullseye.
  • GUI clean up in the main screen/window.
  • Launched 64 bit support for Raspberry PI OS – Bullseye – this is delivered as a separate application – available to download for registered users of Z-LiveRec. Note: This version is still for experimental uses. (Please note: a 64 bit application will not run in a 32 bit OS and vice versa – and the auto update function will currently not work.)

Some Other notes

  • An USB Stick must have a proper set label name – before use with Z-LiveRec. (When using default or none label – errors will otherwise occur when recording)
  • Verified that 2GB wave splits (when using *.wav to not violate the format) does not generate any delay between splits. Checked and verified in Cubase 11 – no delays found between files.
  • If experiencing many buffer overruns problems when using exFAT and doing recordings with W64 and with many channels – a too slow USB stick could be the root cause. It looks like changing to NTFS file format can improve the situation. Another recommendation is to use Sandisk Extreme Go USB 3.2 Flash drives with 64GB – which has a read speed of 395 MB read/s and a write speed of 100 MB/s. Compared to the Sandisk Ultra Slim Fit – which has a read speed on 150MB/S and a write speed on 55MB/S – the Extreme GO USB stick can improve the situation with experienced buffer overruns a lot! (e.g Zero overruns!)
  • More details about Z-LiveRec 2.25 can be found in the manual for V2.25

A free update is available for registered users (Login to “My Account” and download the latest edition or use the e-mail download link from the original order acknowledgement) and free demo/trial version is also available for everybody else to try the app!

Please note: Using the auto update function in Z-LiveRec (for registered users) – You will find a zip file in the PI/Home directory – and you can just extract the zip file yourself – and the V2.25 version will show up.

The update process will try to unzip Z-LiveRec and overwrite the old version of the app – and a chmod r+x command can be required to get the V2,25 version to run again. See the manual for more information.

Best Regards

Anders /

Z-LiveRec V2.24 launched!

Some real improvements and bug fixes are included:

  • Multilanguage support – some country localizations captures some Unix commands and answers in local language when going from UTF-8 to something else. A change in Z-LiveRec made it possible to use the app with any localization of Raspbian OS. Tested and verified to work for English, French and German language settings.
  • A proper split function for wave files is now implemented – so if recording wav file formats – a seamless file split will occur at each 2GB. The file names are autogenerated with xxxxx001.wav, xxxxx002.wav, xxxxx003.wav etc.
  • The new play “slider” have been improved to better handle several transfers and jumps back and forward in the playing file without any problems.
  • Minor fix when enabling auto update or auto start functionality in Z-LiveRec, will now request for PI password for sudo operations with hidden characters. (It does not store the password!)
  • Added auto update events and data in the Z-RecLive.log file.
  • Added replay operations data in Z-LiveRec.log file.
  • Update hard disk sizes when toggling between storage devices in touch mode.

A free update is available for registered users (Login to “My Account” and download the latest edition or use the e-mail download link from the original order acknowledgement) and free demo/trial version is also available for everybody else to try the app!

Please note: Using the auto update function in Z-LiveRec 2.23 (for registered users) – You will find a zip file in the PI/Home directory – and you can just extract the zip file yourself – and the V2.24 version will show up.

Z-LiveRec V2.23 launched!

Finally – a new version launched of Z-LiveRec! The goal with this edition was to “touch” enable the application to 100% so you don´t need a keyboard when running it on a 3.5″ touch screen. (This is the first step to create a new GUI) Another goal has been to close the gap for the app to become “The virtual soundcheck tool” – were we now added better functionality for fast forward & backwards using a slider to jump in the recordings when playing. More functionality will follow! And of course – some small changes and bugfixes.

Change list and new features in V2.23:

  • A transfer slider added to the replay function – you are now able to jump/transfer in the recordings when replaying and move forward and backwards to a certain play point – Perfect for virtual soundchecks! You can see time locator update when moving the slider forward/backward – the player will continue playing at the selected time when releasing the mouse button or pen.
  • A 100% touch based GUI (When enabled in the license dialog window – select the “Touch” checkbox). Perfect for Raspberry PI implementations with 3.5″ touch displays. The main page dropdown lists will is converted to label buttons instead in the touch mode showing the actual selection of setting – and by clicking on the button will toggle and increase the value – e.g. channels 2, 4 ,8 etc, storage devices and file format.
  • In the license dialog window – when entering e-mail address and also license key – a pop up onscreen keyboard is visible – just perfect for Raspberry PI implementations with 3.5″ touch display.
  • More information added to the log handling, (Z-LiveRec.log) when replaying sound files.
  • Added functionality to determine file information – when opening multitrack files for replay, Z-LiveRec now checks the amount of channels, bits deep and time length. Z-LiveRec always uses 24bit when recording to keep file sizes low. But when replaying multitrack files changed in popular DAW applications – most of them will save the multitrack files in floating 32bit format. Z-LiveRec can now automatically detect and read these files.
  • Added support for Raspberry PI Zero WH – a bit limited and slow – but it can handle up to 8 channels using Wav/CAF.
  • Added support for Raspberry PI Zero 2W can handle up to 32 channels in Wav/CAF file format. (Note: Can’t handle 32 channels in the W64 format which “eats” more resources.)
  • Fixed the open file dialog so it is centered to the Z-LiveRec app – not to the actual screen.
  • Performance optimization of threads
  • Fixed the Z-LiveRec logo so it points to
  • Checking license at boot.
  • Some bug fixes.

A free update is available for registered users (Login to “My Account” and download the latest edtion) and free demo/trial version is also available for everybody else to try the app out!

A small bug was found in a late stage of the launch of V2.23 and that is for the auto update function found inside Z-LiveRec – where it does not update the existing app exe. This is for both V2.21 and V2.23 – You will find a zip file in the PI/Home directory – and you can just extract the information yourself – and the V2.23 version will show up. This bug will be fixed in V2.24.

Have a look at the Z-LiveRec product page.