john12ax7

AES Digital 4x1 switch
« on: January 02, 2018, 01:51:55 AM »
Do any digital switch projects exist? I need something to select from 4 AES signals to go into 1 output.

Do any considerations need to be made to avoid pops and clicks when switching?


Michael Tibes

Re: AES Digital 4x1 switch
« Reply #1 on: January 02, 2018, 08:36:55 AM »
You could probably try a simple break before make switch. I assume that 'clicks and pops' in the data stream should be suppressed, depending on the receiver. If there are 'clicks', the data stream becomes 'faulty' and the receiver should mute. Anyway, it is easy to try out.

That would be the simplest version. of course it can be made a lot more complicated ;)

Michael

squarewave

Re: AES Digital 4x1 switch
« Reply #2 on: January 02, 2018, 02:10:02 PM »
Presumably a professional solution would use an IC that understands AES framing and switches at the right moment. But a logic IC w/ 4 tactile momentary buttons and output buffers might work well enough. I would think it would be better than a conventional switch anyways.

john12ax7

Re: AES Digital 4x1 switch
« Reply #3 on: January 02, 2018, 04:08:53 PM »
Anyone have a  Dangerous dbox schematic? Essentially looking to make an add on unit to get more digital ins. It's possible the aes receiver suppresses errors already which makes switching easier.

ruairioflaherty

Re: AES Digital 4x1 switch
« Reply #4 on: January 02, 2018, 11:20:02 PM »
Anyone have a  Dangerous dbox schematic? Essentially looking to make an add on unit to get more digital ins. It's possible the aes receiver suppresses errors already which makes switching easier.

I've never seen a Dangerous Schematic in the wild. 

If it's only for this very specific use case then it's super easy to test, monitor your dbox output on headphones and plug out an AES source and plug in a new one while running audio.  What happens?  It should just mute and be a benign transition if it's designed right.

I know of at least one commercial product that hard switched AES this way and I never heard reports of an issue.
« Last Edit: January 03, 2018, 12:45:58 AM by ruairioflaherty »

Rochey

Re: AES Digital 4x1 switch
« Reply #5 on: January 03, 2018, 08:43:44 AM »
Most AES Receivers will auto mute on signal loss.
Therefor, hard switching should be fine.
Your only other option will be to integrate 4x AES recievers, and switch on zero crossing. (Which is nuts)
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