Saturday 30 April 2022

Cubase Re-Lited Part 1

In the mid-1980s my parents kindly bought me a Casio CZ-101. It was a great introduction to synthesisers and my way back into keyboard instruments. I had been introduced to synthesiser music thanks to some of  school friends lending me albums by Jean Michel Jarre (Oxygene and Equinoxe), Vangelis (L'Opera Sauvage, Apocalypse Des Animaux, Heaven and Hell) and Tomita (Pictures at An Exhibition, The Planet Suite).

At the time I'd been learning the trumpet, but my mum was well-known in the locality, for playing the piano and organ in primary schools and working-men's clubs, alongside teaching piano the music theory, but I was never able to pick it up - my sister did much better than me, getting up to grade 3 or 4.

The CZ series was largely dismissed since the 1990s, primarily because CASIO wasn't associated with professional instruments; the Yamaha DX series were more capable, but also because new synthesis techniques superseded this early digital techniques. However, in recent years, as artists have increasingly mined and revisited older technology, Phase Distortion and the CZ series has been re-evaluated, alongside the emergence of DAWless production.

Over time I acquired a few more instruments: a Yamaha SY-22; an early Sample and (FM) Synthesis, but capable of creating interesting dynamic soundscapes thanks to its vector synthesis feature. For a while I had a Roland MT-32, which could handle up to 8 parts + a drum kit channel.

Around the same time I bought a copy of Cubase lite (bundled, I believe with a MIDI interface) for my Macintosh Performa 400 and with it sequenced quite a number of pieces and songs. Cubase Lite was well within my needs and even when running on a Mac Plus, it could handle everything I threw at it.

Stupidly I sold it because I didn't think that its sounds were particularly interesting and I never took the opportunity to learn how to program it properly. Finally, I bought a super-ugly Yamaha TQ-5 (for £35 on Ebay); which is a superb 4-operator FM synth / sound module with a built-in sequencer (horrible UI) and an effects unit. It's badly underrated as it's better than a DX-11.

Over the past two decades though I've used Garage Band for my music creation - again, because although it's an entry level program, it's still within my needs What I did miss was being able to connect Garage Band to my earlier synths.

However, now that DAWless music creation has become more fashionable, I thought I'd have a go at trying to re-unite my current keyboards and sound modules with a cheap or free, but simple to use DAWless MIDI application.

And it turns out that's quite a rabbit-hole. It's not that nothing is available. For example, there's a Linux program called RoseGarden. Now, typically, the first question I ask about any application, whether it's for Linux, macOS or whatever, is what are the requirements in terms of RAM and CPU? RoseGarden says it's "demanding". What does that mean? A 1GHz Athlon? A 2.5GHz Core i7? A Raspberry PI 3? Muse looks good, but there's no description at all about the hardware requirements. And at this point I'm already turned off. Why make the effort if my hardware might not run it? Also, as software developers have shifted from producing sequencers to full Digital Audio Workstations, they've blurred the descriptions of what their software does. For example, obviously Garageband does handle MIDI input, but it doesn't handle MIDI output, so I've found it progressively harder to figure out whether a given application would support what I want, or even how to ask the right kind of search question that would provide an answer.

Also, it's such a pain even just finding out about trivial things. Consider part of the Support FAQ (which of course, doesn't even tell you what CPU performance you need):

“MusE requires a high performance timer to be able to keep a stable beat. It is recommended that your operating system be setup to allow at least a 500hz timer, MusE will warn you if this is not available.”

An 8MHz Mac Plus could do this! An Atari ST could do this! An Amiga could do this! A 1980s PC running MS-DOS Could. Do. This! 

So, in the end, I figured that if a mid-80s 16-bit era computer (yes, the 68000 is 32-bit) and emulators for these computers are available that run much faster than the original hardware, then surely it should be possible to get an emulation of a Mac to run my original Cubase Lite and communicate with a MIDI interface.

Picking An Emulator?

Mini VMac

My normal go to Macintosh emulator is miniVMac. It is great and and easy to install on a number of platforms. It's also not too heavy on hardware requirements as it makes efforts to maximise emulator performance.

Also, someone has tried to interface miniVMac to real Midi hardware.

“Hi, i've implemented a midi bridge for Mini vMac which exposes emulator modem and printer midi ports to the host OS. so far no stuck notes, and sysex seems to work both ways. there's systematic jitter though which needs to be resolved.”
The cause of the systematic jitter is fairly easy to understand. Mini Mac has a fairly simple emulation core, which aims to emulate execution in 1/60th of a second chunks. That is, it works out how many instructions can be executed in 1/60th of a real second, according to the emulator's requested speed and executes them all in one go. It's not quite that simple, within the basic emulation loop it actually executes instructions until the next interrupt, but the same principle applies. It means that mini vMac only synchronises every ≈16.67ms. The upshot is that mini vMac receives MIDI events prior to its time slice all at once; sends multiple events too quickly during its time slice and worse still, is unable to send events prior to its time slice, as that would mean generating events backwards in time.





This is why messages end up with jitter. Now, the jitter is often not very noticeable, because there often aren't that many events every 17ms, but for an application which requires sub-millisecond latency, it will be enough to mess up recording and playback.

The developer of MiniVMac is slowly making progress on this (see newsletters 9 and 13), but for me, it's a non-starter.

Basilisk II

Basilisk II isn't capable of emulating a Mac Plus, instead it aims to emulate 68020 to 68040 Macintosh computers. Well, at least the most significant ones. Unfortunately, one of the ones it doesn't emulate is my Performa 400 (a.k.a LC II). In addition, Basilisk II substitutes the emulation of real Mac hardware with drivers to the equivalent peripherals. This will work in most circumstances, but if I understand things correctly, applications like Cubase Lite actually addressed the real hardware, in this case the SCC serial communications controller; rather than go through the driver.

PCE/MacPlus Emulator

I'd come across the PCE MacPlus emulator because of the Javascript version:

https://jamesfriend.com.au/pce-js/

I had originally thought it would be rather sluggish, because it was in Javascript, but in reality it performs pretty well. It was only very recently that I actually followed the links and found out it was a conventional emulator written in C++ and ported to Javascript. Importantly, it's possible to browse through the source code, at which point I found this crucial line:

#define MAC_CPU_SYNC 250
With a comment to say that the emulator is sync'd to the emulating computer that many time per second. So, I reasoned that, if I increased it to 1000, then the emulator's serial I/O's latency would be  

Then I came across a ToughDev article about using the PCE emulator to develop classic Macintosh applications, which gave a decent walkthrough:


Building it shouldn't be that hard, you just need X11-dev and SDL (the Simple Direct Layer) libraries, which I tried to first brew the build on my Mac mini; and later used apt-get on a Linux PC, but unfortunately in both cases, the configuration stage said SDL wasn't there.

So, then I tried it on a Raspberry PI 3 I had to hand, but the Raspberry PI 3 had its own problems with the latest version of apt-get. It kept complaining with messages a bit like:

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://archive.raspberrypi.org/debian buster InRelease: Splitting up /var/lib/apt/lists/archive.raspberrypi.org_debian_dists_buster_InRelease into data and signature failed
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://raspbian.raspberrypi.org/raspbian buster InRelease: Splitting up /var/lib/apt/lists/raspbian.raspberrypi.org_raspbian_dists_buster_InRelease into data and signature failed
W: Failed to fetch http://raspbian.raspberrypi.org/raspbian/dists/buster/InRelease  Splitting up /var/lib/apt/lists/raspbian.raspberrypi.org_raspbian_dists_buster_InRelease into data and signature failed
W: Failed to fetch http://archive.raspberrypi.org/debian/dists/buster/InRelease  Splitting up /var/lib/apt/lists/archive.raspberrypi.org_debian_dists_buster_InRelease into data and signature failed
W: Some index files failed to download. They have been ignored, or old ones used instead.
I found that this was a common problem with libraries being updated to use the new Bullseye OS version, replacing Buster. Eventually I found couple [1], [2] of Raspberry PI forums that told me how to fix it. This meant typing in the following line:
sudo apt-get update --allow-releaseinfo-change
I was then able to follow the rest of the development installation as per the ToughDev web page on compiling PCE.
sudo apt update
sudo apt-get update
sudo apt-get install libx11-dev libx11-doc libxau-dev libxcb1-dev libxdmcp-dev x11proto-core-dev x11proto-input-dev x11proto-kb-dev xorg-sgml-doctools xtrans-dev
sudo apt-get install libsdl1.2-dev libsdl1.2debian
One problem I had was at the configure stage, I couldn't get it to acknowledge that SDL's configuration output supported SDL. It would always say things like:
Terminals built:         null x11
Terminals not built:     sdl

 To make it compile with SDL I had to type:
./configure -with-x --with-sdl=1 --enable-char-ppp --enable-char-tcp --enable-sound-oss --enable-char-slip --enable-char-pty --enable-char-posix --enable-char-termios
cp /usr/local/etc/pce/pce-mac-plus.cfg .

At this point I had a version of PCE that could actually run. In part 2 I'll describe the steps needed to get PCE to work as I'd intended.




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