Zimaboard 2 Recording Rig

For the second unit I will be aiming to provide a central point to take my recorded audio and work on it across different machines at home.

In previous builds getting into the innards of the recording box to remove the portable SSD was difficult, as was getting at the lattepanda to connect it to my network.

In addition to this I also found myself mixing across different devices depending on where I was and what I was doing. Currently I have a laptop, mac mini, MS Surface and Windows gaming machine that I have Reaper installed on. Hopping between devices is a nightmare; each instance must be kept identical, which involves ensuring all instances have the same VST plugins and effects used in each project. I've tried centralising my content before on my home NAS, but that has given poor results as WiFi proves a bottleneck.

The proposal for the second unit it to turn the Zimaboard into a dedicated music server, complete with everything every device could need to edit.

I will create two fileshares:

Audio Projects - this will host the audio and project files for Reaper

VST plugins - this will be a central folder for all VSTs and plugins I use in my projects.

I will add both of these shares to all my machines so they can use them as a source.

I'd like to take advantage of the Zimaboard's dual 2.5G ethernet ports here, and connect via ethernet (using the device's ethernet ports or USB>2.5G ethernet dongles) to work from this central network setup without suffering from the problems I had with WiFi. All devices I use for mixing and editing connect to my home network via WiFi so all have that free ethernet port to use.

I will also create two VMs:

one will be a lightweight Debian headless VM for monitoring the network/s the unit is connected to. Upon detection of the other Zimaboard's MAC address being connected to it a sync will be triggered, ingesting any new projects and audio to the Audio Project fileshare.

For the second VM I'd like to create a full Windows/Linux desktop with Reaper installed, with access to the fileshares; I'd like to test whether remoting into the device and using the VM to mix and edit is feasible, as if it is it means I can remove my many instances across my machines and use the attached box as an all in one device.

Future improvements

The projects I edit aren't usually that VST-heavy; I tend to mostly prepare the recorded audio, comp together final takes, then send them to an audio engineer for mixing for release. However, for my own personal recording where I record guitars and vocals in addition to brass and use drum plugins it can get quite plugin-intensive.

One concern is how much the intel N150 CPU can handle before it would struggle with larger projects.

In order to help the CPU as much as possible I have been looking into DSP (Digital Signal Processing). Universal Audio create a fantastic array of Audio interfaces and PCI-e cards that work exclusively with their plugins and offload their processing to their own interface or PCIe card. The devices are expensive, as would be repurchasing Universal Audio versions of the effects I like to use, but doing so would be a great long-term investment. 

I believe this project would be great to demonstrate the power of this on-device DSP processing, so I have reached out to Universal Audio to see which of their interfaces or PCIe cards would be best for this. I believe the PCIe card may be the best fit, as it could fit in the footprint of the NAS enclosure and hopefully keep the audio coming from whichever device is running the VM. 

The purpose for this setup to be taken out into the field to record rehearsals and gigs, store the raw audio and return it to be edited and mixed at home. 

The hope is that with a quick and easy recording setup it will not be a chore to mic up our rehearsals and gigs and yield a lot of raw audio, with that audio potentially being releasable. This will mainly be used with my 8-piece brass group, Small Town Brass, but will also be used with my other bands such as the Welfare Collective. The rig can also be used to record other band performances too on a freelance basis.

Hardware Outline

The Zimaboard will be mounted in its NAS Kit case, allowing two SSDs to be mounted in some 2.5" to 3.5" adaptors. In the future when looking to encase the Zimaboard and the mixer I may opt to move away from the kit's chassis and swap the two SSDs for a single external drive to keep space consumption down. I do hope to keep it on the chassis though, as the mounted bracket for PCI-e use is a great touch, and could be handy for future expansion.

The Behringer XR18 has two points of connection to the Zimaboard; firstly via USB to record the audio over, and secondly is via ethernet to allow for the mixer control software to interact with the mixer. The Zimaboard lacks native WiFi and I also do not want to waste resources on running a software Access Point on the SBC, so I will add a mobile router to the build. The mobile router has 2 ethernet ports so allows for the two devices to be connected. It also adds WiFi, so I can connect to the setup from my laptop, tablet or even phone to operate.

Software Outline

The Zima OS allows for VM and container use out of the box, so I am going to try using a combination of the two rather than wiping the OS and putting Windows or Linux on, although that remains an option should performance be impacted by using ZimaOS almost like a hypervisor.

Firstly I will setup a RAID array using the two mounted SSDs, and use these to store the captured audio. Secondly I will use ZimaOS to set up an Ubuntu VM and install my recording software of choice, Reaper, and the Behringer's mixer control software. Remoting into this VM will give complete control over the mixing and the recording all from one spot.

Reaper offers the ability to run a web interface with custom html, so I will aim to create controllers set to sit nicely on phone or tablet screens. 

In addition OSC is a fantastic protocol that can be used to control various aspects of the software too. There are several OSC apps (and an app for controlling the mixer called Mixing Station) available for android and iOS, so fully remoting into the VM may not be required.