So I'm trying to figure out Guitarix but I'm stumped. Part of it is a lack of time to futz with it and part of it is just ignorance. So here is where I am. I'm using a presonus audiobox usb. In the Jack setup, it's the hw:USB under interface. In this image, you should be able to see the layout. When I go to connections in Jack, I don't see Audiobox in the Audio section. Only in the Midi and Alsa sections, but both of those say Midi and that's not what I want.
The capture and playback entries under “system” represent the ins and outs of your Audiobox. Also, it is typically better to use three periods per buffer when using a USB interface. I strongly recommend using Cadence and Catia to set up JACK.
So it looks like I have a soundcard issue of some sort. I tried to play a simple youtube video and there was no sound there. I'll have to sort that out first.
Slow down, mate. I am almost certain that the web browser you were using expected to use the PulseAudio sound system, and I do not see a PulseAudio bridge in your JACK setup. Do you understand what ALSA, JACK, and PulseAudio are and how they are used?
ALSA is the Advanced Linux Sound Architecture. It is the driver layer which makes your audio hardware accessible to Linux. JACK is the Jack Audio Connection Kit (a recursive acronym). It is a routing layer which can use various backends, such as ALSA, to manage connections to and from your audio hardware. It is primarily used by “professional” programs like DAWs and audio plugins, though various media playback programs (e.g. MPlayer and VLC) can be set to use it directly. Using JACK with “normal” audio programs requires that your either set them to use ALSA (the old way of doing things) or set up a JACK/PulseAudio bridge (the current way of doing things). JACK understands multichannel audio such that individual ins and outs can be routed. PulseAudio is a routing and mixing layer which uses ALSA as its backend, though it is not suitable for professional audio due to various shortcomings with regard to timing. It is the current standard for “normal” audio programs, such as web browsers and Steam. PulseAudio only understands multichannel audio with regard to consumer surround sound, thus your primary playback channels will always be mapped to your first two playback channels. I use Cadence to start JACK with a PulseAudio bridge (“ALSA -> PulseAudio -> JACK (Plugin)”), then use Catia to send my mixer's “Capture 1” channel to the PulseAudio bridge's “Capture 1” and “Capture 2” channels and my mixer's “Playback 11” and “Playback 12” channels to the PulseAudio bridge's “Playback 1” and “Playback 2” channels. This allows me to use my mixer setup with “normal” audio programs, forcing faux stereo for my mic (the way Skype automatically doubles mics in calls). Any JACK programs I use generate their own entries in Catia such that I can assign them to any of my mixer's capture and playback channels.
Ok, so starting off simply. After I plug in the Audiobox USB, I lose sound from Youtube through my headphone interface on the laptop. How do I fix that? KX Studio doesn't appear to have Pulse Audio in it's repositories so I'll have to hunt that down. Right now, all I see in Catia is system capture_1 and capture_2 into jack2alsa playback_1 and playback_2. Then I have the reverse. alsa2jack capture_1 and capture_2 into system playback_1 and playback_2. No matter how I connect them, I don't have any audio from the laptop.
That sounds like the Audiobox is being set as your default audio device when it is connected. I recommend connecting your headphones to your Audiobox: your sound quality will improve, and you will be able to monitor your inputs in real time. The correct search term to use is “pulseaudio” (in other words, do not include a space).
The problem I'm having is twofold. The first is that pulseaudio appears to be a part of Ubuntu's default install so nobody bothers to talk about the repo. Secondly, I use redhat at work exclusively and they have their own custom way of connecting to rpms (which I hate) so I don't know the arcane and back alley places to find things for Ubuntu. I'll find it eventually.
It could be that KXStudio does not use PulseAudio, as a way of avoiding its failings with regard to professional audio work. If that is the case, then setting “normal” programs to use ALSA should be all that you need to do. Has connecting your headphones to your Audiobox allowed you to hear YouTube playback, provided that the Audiobox was connected to your computer prior to starting the web browser?
So here is where I am now. The USB Audio is the Audiobox. I don't get sound out of it or out of the laptop when I play a youtube video. When I unplug the Audiobox, the only thing that disappears is the MIDI1 in and out boxes. The four blue boxes stick around and still don't have audio.
I think the Audiobox might be bad. I did pick it up used for $35 so whatever. I plugged it into my Windows system because I'm more comfortable troubleshooting there. I eventually got it so that the guitar would work in one side of my headphones from the windows soundcard. I then switched the output to the Audiobox to test that and my entire system ground to a halt. I switched back to the soundcard as the output and everything was fine. I wouldn't care if I had to use the onboard sound card so I then installed Amplitube 3 and 4. Neither of them would recognize the unit at all. I'd still hear the guitar on one side through the soundcard, but not through Amplitube no matter what I tried.
The attached screenshot illustrates your problem perfectly; look at your “JACK Settings” window: Notice that the “Input Device” and “Output Device” menus are not available. Notice that you have “0” input and output channels enabled. In short, that is why do you do not have any audio channels for the Audiobox in Catia. Try the following configuration (note that you should do this before starting JACK with Cadence): Check the box for “Duplex Mode.” Selet the Audiobox in both of the “Input Device” and “Output Device” menus. Enter “2” for both of the “Input Channels” and “Output Channels” fields.
Here is the log when I try to do that: p, li { white-space: pre-wrap; } Fri Feb 10 13:23:19 2017: ERROR: Cannot lock down 82274202 byte memory area (Cannot allocate memory) Fri Feb 10 13:23:19 2017: Acquired audio card Audio2 Fri Feb 10 13:23:19 2017: creating alsa driver ... hw:USB,0|hw:USB,0|1024|3|44100|2|2|nomon|swmeter|-|32bit Fri Feb 10 13:23:19 2017: configuring for 44100Hz, period = 1024 frames (23.2 ms), buffer = 3 periods Fri Feb 10 13:23:19 2017: ALSA: final selected sample format for capture: 24bit little-endian in 3bytes format Fri Feb 10 13:23:19 2017: ALSA: use 3 periods for capture Fri Feb 10 13:23:19 2017: ALSA: final selected sample format for playback: 24bit little-endian in 3bytes format Fri Feb 10 13:23:19 2017: ALSA: use 3 periods for playback Fri Feb 10 13:23:19 2017: ERROR: Cannot use real-time scheduling (RR/85)(1: Operation not permitted) Fri Feb 10 13:23:19 2017: ERROR: AcquireSelfRealTime error Fri Feb 10 13:23:19 2017: graph reorder: new port 'system:capture_1' Fri Feb 10 13:23:19 2017: New client 'system' with PID 0 Fri Feb 10 13:23:19 2017: graph reorder: new port 'system:capture_2' Fri Feb 10 13:23:19 2017: graph reorder: new port 'systemlayback_1' Fri Feb 10 13:23:19 2017: graph reorder: new port 'systemlayback_2' Fri Feb 10 13:23:19 2017: New client 'cadence-aloop-daemon' with PID 2814 Fri Feb 10 13:23:19 2017: New client 'jack2alsa' with PID 2820 Fri Feb 10 13:23:19 2017: New client 'alsa2jack' with PID 2819 Fri Feb 10 13:23:19 2017: ERROR: Cannot write socket fd = 14 err = Broken pipe Fri Feb 10 13:23:19 2017: ERROR: CheckRes error Fri Feb 10 13:23:19 2017: ERROR: Could not write notification Fri Feb 10 13:23:19 2017: ERROR: ClientNotify fails name = alsa2jack notification = 0 val1 = 0 val2 = 0 Fri Feb 10 13:23:19 2017: ERROR: NotifyAddClient old_client fails name = jack2alsa Fri Feb 10 13:23:19 2017: Client 'jack2alsa' with PID 2820 is out Fri Feb 10 13:23:19 2017: ERROR: Cannot write socket fd = 16 err = Broken pipe Fri Feb 10 13:23:19 2017: ERROR: CheckRes error Fri Feb 10 13:23:19 2017: ERROR: Could not write notification Fri Feb 10 13:23:19 2017: ERROR: ClientNotify fails name = jack2alsa notification = 1 val1 = 0 val2 = 0 Fri Feb 10 13:23:19 2017: Client 'alsa2jack' with PID 2819 is out Fri Feb 10 13:23:20 2017: ERROR: Unknown source port in attempted (dis)connection src_name [alsa2jack:capture_1] dst_name [systemlayback_1] Fri Feb 10 13:23:20 2017: ERROR: Unknown source port in attempted (dis)connection src_name [alsa2jack:capture_2] dst_name [systemlayback_2] Fri Feb 10 13:23:21 2017: ERROR: Unknown destination port in attempted (dis)connection src_name [system:capture_1] dst_name [jack2alsalayback_1] Fri Feb 10 13:23:21 2017: ERROR: Unknown destination port in attempted (dis)connection src_name [system:capture_2] dst_name [jack2alsalayback_2]
I just noticed that your user is not in the “audio” group; though it may not solve your current problem, you should add your user to the “audio” group and try again.
I added myself to the audio group and that didn't help so I tried something completely different. I noticed in another thread you said you used Ubuntu Studio so I installed that. Guess what? Everything works now. I used all of the settings you gave me in this thread, fired it up, bang. It works. Now I just have to figure my way around Guitarix.
So now I have a new thing to figure out. How to load a preset. When I go to preset selection there is no button to load. Double clicking on a preset in the Bank section doesn't appear to do anything. I downloaded a couple off of Musical Artifacts and I don't see any way to load them either.
I finally figured it out. I didn't find it very intuitive, but it's easy now that I know how. First off, you have to download the presets through Guitarix. There is probably a directory you can download them into but I didn't bother looking. After you've downloaded them, you click on the preset and then you have to click on the preset in the bank and then another screen pops up next to it for sub-presets. After you select one of those, it loads. I did not realize you had to select something in the sub-preset because there was only one option on there for particular bank I'd clicked on. I thought it would automatically load and it didn't.
