Roland GR-55 USB Audio

Talk about your MIDI interfaces, microphones, keyboards...

Moderators: MattKingUSA, khz

Post Reply
merlyn
Established Member
Posts: 639
Joined: Thu Oct 11, 2018 4:13 pm

Roland GR-55 USB Audio

Post 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.
Last edited by merlyn on Mon Jul 29, 2019 9:35 am, edited 1 time in total.

merlyn
Established Member
Posts: 639
Joined: Thu Oct 11, 2018 4:13 pm

Re: GR-55 USB Audio

Post 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.

tavasti
Established Member
Posts: 1080
Joined: Tue Feb 16, 2016 6:56 am
Location: Kangasala, Finland
Contact:

Re: GR-55 USB Audio

Post 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.
Linux veteran & Novice musician

Latest track: https://www.youtube.com/watch?v=ycVrgGtrBmM
More my music https://audiu.net/users/tawaste

merlyn
Established Member
Posts: 639
Joined: Thu Oct 11, 2018 4:13 pm

Re: GR-55 USB Audio

Post by merlyn »

Thanks @tavasti.

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

merlyn
Established Member
Posts: 639
Joined: Thu Oct 11, 2018 4:13 pm

Re: Roland GR-55 USB Audio

Post 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.

merlyn
Established Member
Posts: 639
Joined: Thu Oct 11, 2018 4:13 pm

Re: Roland GR-55 USB Audio

Post by merlyn »

My original reason for plugging my GR-55 into my computer was to use GR55FloorBoard :
GR-55FloorBoard27.png
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
Now I can connect the GR-55 with a USB lead, edit it with GR55FloorBoard, and hear it through my soundcard.
You do not have the required permissions to view the files attached to this post.

Post Reply