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Roland GR-55 USB Audio

Posted: Thu Jul 18, 2019 10:08 pm
by merlyn
Using Drumfix's quirk-table.h addition my GR-55 now appears in arecord -l.

I can select it to start JACK and JACK starts using 1024 frames and 3 periods.

The sample rate is always 44.1k regardless of what I choose in Cadence > Configure.

There is a steady stream of Xruns -- they just keep ticking up. JACK won't use the GR-55 as an output -- the output always falls back to my PCI soundcard, which is working, I can use the GR-55 MIDI to trigger Ninjas2 in Ardour. That makes sense -- I wouldn't want the GR-55 as an output.

I connected the GR-55 audio ins to a stereo track in Ardour and unfortunately there is nothing.

Re: GR-55 USB Audio

Posted: Fri Jul 19, 2019 1:49 am
by merlyn
I got it working! Thanks Drumfix!

It works when the GR-55 is the input and the output. So at the moment my guitar synth is my soundcard. :!: That means in a live setup you could plug the synth into a laptop and have the laptop audio come out the synth into the amp you're using for the synth.

The sample rate is still always 44.1k.

Re: GR-55 USB Audio

Posted: Fri Jul 19, 2019 6:12 am
by tavasti
If you want, you can use your laptop as default interface, and use alsa_in / alsa_out to make additional jack interfaces, and route sounds like you desire in qjackctl / patchage / whateverappyoumayuse.

Re: GR-55 USB Audio

Posted: Fri Jul 19, 2019 10:33 am
by merlyn
Thanks @tavasti.

I've found alsa_in needs a large resampling buffer and therefore a high latency to work without Xruns.

Re: Roland GR-55 USB Audio

Posted: Mon Jul 29, 2019 10:03 am
by merlyn
I updated my kernel to 5.2.0-rt1-1-rt and my GR-55 is recognised as an audio device without recompiling snd-usb-audio.

Looking through quirks-table.h there is no reference to the GR-55, so it must be this generic Roland quirk :

Code: Select all

/* this catches most recent vendor-specific Roland devices */
{
	.match_flags = USB_DEVICE_ID_MATCH_VENDOR |
	               USB_DEVICE_ID_MATCH_INT_CLASS,
	.idVendor = 0x0582,
	.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
	.driver_info = (unsigned long) &(const struct snd_usb_audio_quirk) {
		.ifnum = QUIRK_ANY_INTERFACE,
		.type = QUIRK_AUTODETECT
	}
},
This could have gone into the kernel a while ago as I wasn't checking if the GR-55 audio worked every time I updated my kernel.

Using the GR-55 as a USB audio device is of limited use to me as it only works at 44.1k and I record instruments other than the GR-55. Still, good to know it's there as an option.

MIDI works and can be hotplugged. MIDI has worked since kernel 3.13 on KXStudio.

Re: Roland GR-55 USB Audio

Posted: Tue Sep 17, 2019 7:17 pm
by merlyn
My original reason for plugging my GR-55 into my computer was to use GR55FloorBoard :
GR-55FloorBoard27.png
GR-55FloorBoard27.png (221.21 KiB) Viewed 896 times
The native Linux version stopped working on Arch, so I'm now using it through WINE.

This software highlights Roland's questionable attitude. The menu system on the GR-55 is not user friendly, yet Roland don't provide editing software. This software was written by a GR-55 user. A few years ago I tried to install the GR-55 drivers with WINE. I got a message box from Roland that said 'You are using the wrong operating system'. Of course I thought 'No, you are.' :D

I'm used to workarounds with this -- originally I used two 5-pin MIDI leads to connect the GR-55. Then USB MIDI started working. Now USB audio works. So can I use just one USB lead for everything? Yes.

@tavasti had the right idea above when he suggested alsa_in. However, from the alsa_in / alsa_out walkthrough :
To obtain better results you must use a usb card as jacks native card and use alsa_out with the pci or internal card.
It's counter-intuitive -- using the less good interface as the master, but it works.

Finally zita-j2a works much better than alsa_out so my solution is to start JACK using the GR-55, then use my PCI card as an output through zita-j2a. For GR55FloorBoard to connect to the synth JACK must be started with the ALSA sequencer driver.
GR-55+PCISoundcard27.png
GR-55+PCISoundcard27.png (27.66 KiB) Viewed 896 times
Now I can connect the GR-55 with a USB lead, edit it with GR55FloorBoard, and hear it through my soundcard.