[LAU] Jack max ports question

Len Ovens len at ovenwerks.net
Sun Aug 2 16:05:02 UTC 2015

On Sun, 2 Aug 2015, Gene Heskett wrote:

> I've no clue how universal it could be made to work, but forget the chips
> designation by model/device type unless theres more than one detected by
> the system, and come right out and say its the blue jack that is the mic
> input, the orange jack is the line output. etc etc. I've no doubt played
> mix & match with the color of the jack since I don't have that
> memorized.
> But you get the point.

I had decided not to say anything more... I have also dealt with too many 
people on IRC who don't get it. You can take what Paul deals with on 
#ardour and multiply that but every distro that has an IRC channel.

However, I am not sure the colour labels in the GUI would help. The 
problem would seem to be identifying internal vs. external cards. A jack 
GUI might (with some work) put up a dialog box that says "external audio 
card detected, but internal audio is chosen. Is this what you want?" Then 
have a checkbox that says "Never show this again".

The solution many users expect is the Windows/Pulse solution of showing 
all audio devices and hiding the fact that sample rate conversion is 
happening. The profesional world is not that different, the number of 
cards that take a number of AES3 inputs with a resample stage is not that 
small (some even take mp3 streams in :P ). Certainly the whole AoIP world 
is based on the all i/o are visible and usable concept. (and in sync even)

How much work should the GUI dev put into making sure the user understands 
this not so? Or that this is not a good idea? In fact maybe the user 
understands this is not a good idea, but they have a USB input from their 
mic/guitar and can only use internal audio output to hear themselves. (why 
did they buy such a thing in the fist place?)

There are some very good sample rate converters out there that work with 
jack (well one anyway). Maybe it is time to automate connecting extra i/o 
through s/r blocks. Certainly the idea of being part of an AoIP network 
and having _all_ i/o connected to jack all the time does not make sense. 
Some kind of GUI that allows dis/connecting a remote i/o only when needed 
just makes sense. Most of us here, would want know and choose which AI is 
synced and which is s/r. But a number of others do not care. They just 
want to use guitar/mic in through a USB and audio out through internal or 
even the video conection.

The world of inexpensive PCI audio cards is gone (though I hope to get 
years of service from the one I have). The Linux tools we use need to 
reflect that. There is a difference between what should be and what is. 
Making the best use of "what is" is the way forward in my mind.

Len Ovens

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