1 (edited by Be.0 2021-05-12 09:15:12)

Topic: Babyface Pro on the go with PinePhone + USB hub + battery + speakers

After over 5 years of owning my Babyface Pro I have finally figured out a practical way to use it outside on battery power. iOS is no option for me. Despite the Babyface Pro being USB audio class compliant, it does not work with whatever Android puts on top of ALSA. I suspect that has something to do the alternate USB configuration which presents only 2 channels for iOS applications, but I have not actually looked into the problem. Anyway, I now have a solution with my PinePhone:

https://i.imgur.com/q0FSWAF.jpg

I am using the USB hub that comes with the PinePhone "convergence package" and plugging the Babyface Pro into it. I am plugging the battery into the USB-C Power Delivery port on the hub, which powers both the Babyface Pro and the PinePhone. The PinePhone charges really slowly from the hub, but importantly, it does not drain battery so it can keep playing for a long time.

Unlike many pocket computers nowadays, the PinePhone has a microSD card slot. I have my entire music collection, which is currently 174 GB of FLACs, on a 256 GB microSD card in the PinePhone. I set a fixed mount point for the microSD card in /etc/fstab so music players have a consistent path to scan for music (mounting from Profile or GNOME Files mounts to a different path each time and I'm not sure what determines that path). I have Elisa and Lollypop on my PinePhone. I prefer Elisa, which is what I use on my laptop, but it currently has an annoying bug with one time stuttering a few seconds into the start of tracks, so I am using Lollypop for now. There are several unrelated issues which prevent me from using the PinePhone as my daily driver phone for now, but I have figured out how to make it useful as a portable music player already so it's not just a fun toy.

The speaker is my trusty old Bose Sounddock Portable which is still working well after 10 years. This battery has a 20 V DC output so I can charge the Bose Sounddock Portable directly without needing an inverter and the bulky AC adapter that came with the Bose Sounddock Portable. Its capacity is huge with 266 Wh. I suspect I could use this setup over a whole weekend at a festival without needing to recharge the battery.

This whole setup fits in a normal size backpack and it isn't too heavy.

Notably, there is a faint high pitched ringing sound when everything is connected which goes away if I disconnect the battery from the Bose Sounddock Portable. I do not know what causes that but it is not too bothersome when music is playing. I would appreciate any suggestions to investigate or alleviate that.

Re: Babyface Pro on the go with PinePhone + USB hub + battery + speakers

I bet you hear the inverter in the Bose SoundDock. It's ten years old. Caps in such a PSU lead a hard life.

If you feel up to it, replace all electrolytics in the PSU section and you're probably good for another decade or so.

Re: Babyface Pro on the go with PinePhone + USB hub + battery + speakers

I figured out that the high pitched hum it is somehow an artifact of connecting all the devices to the same battery. If I power the PinePhone and Babyface Pro from a different battery pack while charging the speakers from that bigger Renology battery pack, there is no high pitched hum.

I got a ZMI PowerPack 20k Pro which is a battery pack that doubles as a USB hub. However the USB hub functionality is not working for me. It came with a short USB-C to USB-C cable and a long USB-C to USB-C cable for charging. When I switch it to hub mode and plug in with the short cable, either to my laptop (Lenovo Yoga 920) or my PinePhone, dmesg shows:

[170497.081229] hub 4-0:1.0: USB hub found
[170497.081252] hub 4-0:1.0: 2 ports detected
[170498.029555] usb usb1-port6: Cannot enable. Maybe the USB cable is bad?
[170498.029639] usb usb1-port6: attempt power cycle
[170499.293596] usb usb1-port6: Cannot enable. Maybe the USB cable is bad?
[170500.245545] usb usb1-port6: Cannot enable. Maybe the USB cable is bad?
[170500.245622] usb usb1-port6: unable to enumerate USB device

If I use the long USB-C to USB-C cable, dmesg shows:

[171365.862614] hub 4-0:1.0: USB hub found
[171365.862629] hub 4-0:1.0: 2 ports detected
[171366.489474] usb 1-6: new high-speed USB device number 119 using xhci_hcd
[171367.445565] usb usb1-port6: Cannot enable. Maybe the USB cable is bad?
[171368.397564] usb usb1-port6: Cannot enable. Maybe the USB cable is bad?
[171368.397659] usb usb1-port6: attempt power cycle
[171369.034534] usb 1-6: new full-speed USB device number 121 using xhci_hcd
[171369.034717] usb 1-6: Device not responding to setup address.
[171369.238657] usb 1-6: Device not responding to setup address.
[171369.446569] usb 1-6: device not accepting address 121, error -71
[171369.560525] usb 1-6: new full-speed USB device number 122 using xhci_hcd
[171369.560678] usb 1-6: Device not responding to setup address.
[171369.765593] usb 1-6: Device not responding to setup address.
[171369.973489] usb 1-6: device not accepting address 122, error -71
[171369.973606] usb usb1-port6: unable to enumerate USB device

Maybe I've stumbled into USB-C compatibility hell. I'll try getting different USB-C cables. I can already use the ZMI PowerPack 20k Pro by using it to power the Pine USB hub, but it would be nice to not need the Pine USB hub.

4 (edited by Be.0 2021-06-17 05:32:29)

Re: Babyface Pro on the go with PinePhone + USB hub + battery + speakers

It turned out that the issue I had with the ZMI PowerPack 20k Pro was a defective unit. I exchanged it for another and now it works great with my PinePhone. I can now power my PinePhone and connect my Babyface Pro with one device.