Jan 8 2018, jonetsu has written: ... JACK sits ontop of ALSA (or another hardware driver). No. ALSA is the hardware driver for your audio/MIDI interface(s). It implements a communication between the Linux kernel and the hardware or firmware on the soundcard. Then it offers an API to programs using audio. So there are specific functions that you can call in a C/C++ program. You can use the same functions for any soundcard, without worrying what the soundcard really needs to do to fulfill your request. You can just say: give me two audio channels at 17bit and 44.1kHz for recording. This will work for any soundcard that can give you those two channels. If not it, the ALSA API will return a standard error. JACK sits ontop on an even higher level. It does its best to give you lowlatency and some guarantees. It also gives you the software patch system with all those JACK ports that you can connect as you please. This allows you to connect software to hardware, hardware to hardware or even two programs. That's a very rough answer, possibly false in many respects, but unless you need to really delve into all that, it is true enough from the user's point of view. :) HTH, best wishes, Jeanette ... -------- * website: http://juliencoder.de - for summer is a state of sound * SoundCloud: https://soundcloud.com/jeanette_c There must be another way Cause I believe in taking chances But who am I to say - What a girl is to do <3 (Britney Spears)

On Mon, 8 Jan 2018, jonetsu wrote: Jackd requires some sort of back end. Most of us use ALSA, but jackd can also use the ffado for firewire devices, or net for talking with a remote jackd. There is dummy backend that talks to nothing but provides sync and makes jackd feel like it has all it needs. Aside from the backend, jackd can talk with audio devices as clients. I know of four clients like this (there may be more) alsa_in and also_out which come with jackd allow jackd to talk to an audio device that may be out of sync with it's backend, zita-ajbridge is similar but features better quality with less cpu use. Zita-njbridge connects jackd over the net to another jackd. The last one I know are a set of utilities that allow jackd to be connected over the network to an AVB box. I am sure I have not covered everything... -- Len Ovens www.ovenwerks.net

On 08/01/18 22:57, jonetsu wrote: I have some home-grown MIDI devices which are based on Arduino processors. The USB port on an Arduino insists on appearing in Linux as a TTY device. I have written my own TTY -> Jack handler. I still use ALSA for 'normal' audio/MIDI devices in parallel. Bill -- +----------------------------------------+ | Bill Purvis | | email: bill(a)billp.org | +----------------------------------------+