[LAU] MIDI to USB latency problem

[Janina Sajka]

Hi,

I've not been active here for quite some time. So, I've tried something
simple to get my toe back in, as I need to distribute MIDI files to some
musician colleagues.

So, I've wired an old Yamaha 49-key keyboard into Fluidsynth using a
Textech MIDI to USB cable, and provided the aconnect command.

I have sound, but it's about 300 ms latent--effectively unusable.

Fluid synth did complain: "Failed to pin the sample data to RAM." Could
that possibly explain this much latency?

I'm loading Fluidsynth for alsa_seq because I don't believe I need the
complexity of jack just yet. But, might jack do better?

Any suggestions most appreciated.

Janina


Len Ovens writes:
> 
> 
> On Tue, May 21, 2013 11:31 am, Robin Gareus wrote:
> > [message re-arrange to avoid top-posting]
> > On 05/21/2013 04:52 PM, Axax wrote:
> >> On 05/21/2013 09:30 AM, Abhayadev S wrote:
> >>> Hi,
> >>>
> >>> Anybody had tried using the Focusrite Scarllet 8i6 on Ubuntu Studio
> 13.04?
> >>>
> >>> So far it was not supported under ALSA but from 13.04 it seems it is
> been detected and the JACK is able to list out couple of I/Os.
> >>>
> >>> Last day i just booted up a live version of the 13.04 and was bale to
> do couple of i/o routing. Jack lists 8 inputs and 12 outputs. It seems
> the Inputs 1 to 4 (analog mic/line-ins) are listed as Inpiuts 1 to 4
> and 2 SPDIF are 5 and 6. But i am not sure about the 7 and 8. I am
> getting the same SPDIF signal on these inputs too !
> >>> The output 1 to 4 are Monitors output (1&2) and extra outputs (3&4) on
> the backside of the box. And 5&6 seems to be SPDIF outputs. Still have
> 6 more outputs to be listed/clarified.
> >>>
> >>> Just going ahead with further analysis and if anybody out there has
> any thing to add on please do so..
> >>>
> >>> Regards,
> >>> Abhayadev S
> >>> http://sites.google.com/site/abhayadevs
> >>> http://sites.google.com/site/astudioindia
> >>>
> >
> >> Hi,
> >>
> >> I've the same audio card. It's working as you described, but I can't
> figure out hot to change the input mode for the channels 1-2 from MIC
> to LINE/instr!
> >> Anybody have a clue?
> 
> Just a quick addition. The below describes how to change the
> line/instrument inputs back and forth. Mic to line is automatic. If you
> plug into the XLR it is mic mode and into the 1/4inch TRS (or TS) it is
> line/instrument mode.
> >>
> >> A.
> >>
> >
> > see
> > https://focusritedevelopmentteam.wordpress.com/2012/04/23/linux-and-focusrite-novation-products/#comment-51
> >
> > https://github.com/x42/alsa-driver/tree/s18i6  adds full mixer support
> for the 18i6. According to Focusrite the same will also work for the 8i6
> -- but I lost interest in Focusrite devices for various reasons.
> >
> >
> > Short of patching the alsa kernel driver or using another OS to change
> device config, you can use https://github.com/x42/scarlettmixer to
> change the config on GNU/Linux. It's not a ready-to-use app, however:
> >
> > 1) rmmod snd_usb_audio  # so that python script can access the device 2)
> change the python script line 31 to detect the 8i6
> > 3) tweak the "example code" line 492..
> >   the "line/inst" switch is there as sw_impedance()
> > 4) modprobe snd_usb_audio # ...
> >
> > best,
> > robin
> > _______________________________________________
> > Linux-audio-user mailing list
> > Linux-audio-user at lists.linuxaudio.org
> > http://lists.linuxaudio.org/listinfo/linux-audio-user
> >
> 
> 
> -- 
> Len Ovens
> www.OvenWerks.net
> 
> 
> 
> -- 
> Len Ovens
> www.OvenWerks.net
> 
> _______________________________________________
> Linux-audio-user mailing list
> Linux-audio-user at lists.linuxaudio.org
> http://lists.linuxaudio.org/listinfo/linux-audio-user

-- 

Janina Sajka,	Phone:	+1.443.300.2200
			sip:janina at asterisk.rednote.net
		Email:	janina at rednote.net

Linux Foundation Fellow
Executive Chair, Accessibility Workgroup:	http://a11y.org

The World Wide Web Consortium (W3C), Web Accessibility Initiative (WAI)
Chair,	Protocols & Formats	http://www.w3.org/wai/pf
	Indie UI			http://www.w3.org/WAI/IndieUI/