Re: [Line6linux-user] HD300 and Jack

[Cristiano A. <cri...@ti...>]

ok, after some more testing I have understood the problem!
It seems that Jack does not recognize the audio card of my PC. In the 
Setup window of QJackCtl I select duplex, and I can see the interfaces 
of both the POD and the built-in audio card. Thus I select the POD as 
input and the audio card as output device. However, when I open the 
Connection window, the built-in card does not show up. In the audio tab 
I can only see the menu for ardour and a menu "system" that refers to 
the POD (yes, I am sure...if I disconnect the system output to the 
system input I cannot hear sound from the headphones attached to the 
POD, and if I disconnect system out to ardour input, ardour does not get 
the guitar signal).

Any help would be highly appreciated!

Thanks
Cristiano


On 05/28/2014 08:22 PM, Cristiano Alessandro wrote:
> Hi Stefan,
>
> thanks for your reply.
> I have followed your suggestions and everything seems to be running. I 
> can start the Jack server, and I can even define different audio cards 
> for input and output. It works!
>
> However nothing comes out of the speakers. I have checked Alsa mixer 
> and all the lines are in maximum volume. I am sure that the signals 
> arrives to the PC, because I can record in Ardour and I can see the 
> waveform, but I cannot hear anything. Not even if I play the track 
> recorded in Ardour.
> Any idea?
>
> Thanks
> Cristiano
>
>
>
> On 05/28/2014 10:42 AM, Stefan Hajnoczi wrote:
>> On Wed, May 28, 2014 at 9:47 AM, Cristiano Alessandro
>> <cri...@ti...> wrote:
>>
>> Great, the driver is working and the sound card is available.
>>
>> First, launch pavucontrol and disable the HD300 in the Configuration
>> tab.  This ensures that PulseAudio will not interfere while JACK is
>> using the device.
>>
>> If you wish to hear the guitar on your PC speakers, also disable your
>> PC sound card in pavucontrol.
>>
>> Now launch qjackctl.  If you want to use the HD300 for playback and
>> capture, select HD300 as the Interface and make sure Audio is Duplex.
>> Set Frames/Period to 128, Sample Rate to 48000, and Periods/Buffer to
>> 2.  Now click click Start to launch the JACK daemon.  This is the
>> configuration that I use.
>>
>> But it sounds like you want to use the HD300 as the capture (in)
>> device and your PC soundcard as the playback (out) device.  In that
>> case you need select the Input Device and Output Device separately.
>> I'm not sure how great JACK is at using two different sound devices -
>> the reason is that they have independent sampling clocks which will
>> drift apart over time.
>>
>> In my setup where everything goes through the HD300 I connect either
>> headphones to the HD300's headphone socket or a PA speaker to the
>> HD300's L/Mono socket.
>>
>> Hope this helps,
>> Stefan
>