Feature request: hot swop


I have a feature request: would it be possible to handle USB-soundcards in hot-swop mode? In detail: it would be extremely helpful if cantabile would be able to detect a vanishing and more important a re-connected soundcard and restart engine.

Atm this is not the case: if I pull the usb cable and reconnect it the soundcard isn‘t remembered by cantabile.

On the other hand turning off and on engine after reconnection by hand solves this problem. Probably it „only“ would need a small detection-routine to automatise this?

For me I‘d see 2 big advantages:

  1. Quick restart after a „disconnect-accident“ on stage (simply plug the USB-cable in)
  2. Very simple and cheap backup-solution using a 2nd Laptop & a small usb switch to connect soundcard to one of the laptops. In case of a crash one push gets me online again. If the soundcard is power-supplied by an active USB-hub I don‘t even hear a „click“ from my babyface.

Thanks and regards, humphrey

The problem with this is that there’s no notification from an asio driver that the sound card has disappeared so it’d have to be some heuristic to try and guess. The most Cantabile would see is the audio callbacks stop coming in, but attempting to restart the drive could cause more problems than it solves at this point.

Hi Brad,

thanks for responding.

Regards, humphrey

I’m having a second thought about the “ignore” behaviour… For example after soundcheck it is not so rare that technicians mess with supply power - this means that the audio interface will disconnect and reconnect.
Now the gig starts and everything looks nice and green but notes will not sound until manual engine restart.
Any other way to handle these situations than to always manually restart the engine before first song? I think it would be helpful if there was a hint or warning so I could maybe anticipate trouble and restart the engine.
I’d rather not always restart if not needed and I cannot always afford to sound a “test note” before start.

Hi Matej,

well, after my idea turned out to be a cul-de-sac I decided to start from scrtch.

I agree that situations as you described can happen. It was not only a single situation I had where someone of the technical stuff cut my mains. Besides I also had few situations where the quality of mains was so terrible that the OS crashed (I have to confess I was not the only one having trouble at this point: the bass player had lots of hum and hiss on his outs, the digital amp of the guitar player had to be restarted during the show.

All this isn‘t really helpful to do a proper job. So I decided to realize a „bullet proof“ mockup for my keys part.

Everything starts with a multiple socket outlet with integrated overvoltage protection. This is useful to cut high energy voltage transients and to protect the next component in the row. This is a UPS which is used to supply all of my keys, soundcards, effects and laptops. It is capable of supplying about 700W for 20 minutes - more than enough for any situation I can think of. This solution has additional advantages:

  • All components are supplied independantly from anything that‘s happening on mains
  • Outputvoltage is aleays super stable and sinusoidal
  • Bursts, sags, radio frequencies no longer make their way to my instruments
  • Protects the equipment

I stii use my 2 laptops but now with two separate soundcards. The main advantage is there is a second identical audio signal available in case of a crash.

To make all this handy I built up a hardware midi-manager (4 Ins / 4 Outs) that can control everything even if one of the laptops should fail. This lttle gem can do several things:

  1. By sending program change 1 or 2 on the lower keyboard the midi manager can change the audio routing in one of my soundcards (fireface ufxII RME). This one is controlled by an adfitional midi in and able to change the routing even if the laptop it is bound to should fail!
  2. Control midi in of my Voice Live 2
  3. Merge midi signals from 2 keyboards if necessary
  4. Control monitor signals of my in ears for monitor band (everything but keys), keys, sequences/backingtracks and my vocals by 4 faders of my lower keyboard
  5. Some more little tricks to be able to use cantabiles webserverinterface for both laptops

This way I got rid of all the mess. Switching from one laptop to the other is so fast and precise that it is next to „not noticable“. I don‘t need to explane anything to the FOH mixers (in most cases they don‘t even know about this.

I agree: this is definitely more expensiv than a standard setup and took me quite some hours to make it happen. Is it really necessary? Probably not. Do I like it? Yess!

My 2 cent, regards, humphrey