OctaMED 8 Channels and MIDI screw ups...

[Karlos]

It's not clear if you are, but as a warning do not, upon pain of death, use the old 5-8 channel mode, except solely play back old mods written for it.

If you are going to use more than 4 channels, use Mix mode. The old 5-8 channel mode has absolutely no advantages of any kind whatsoever (at least in 8 channel mode) and a plethora of annoying limitations.

In contrast, everything you can do in 4 channel mode continues to work just fine in mix mode, including synthsounds, MIDI and you also get support for 16-bit samples (with some volume limitations), stereo samples (ie stereo sample playback from a single channel), channel panning and so on.

I've managed 6 channel mix mode with MIDI on a vanilla 2MB chip only A1200. However, I can't stress enough the improvement you'll get just from few MB of fast ram added to the trapdoor. In mix mode especially, samples in fast ram speed up the mixing allowing more channels / higher mix rates.

As for the PCMCIA ram, I'd actually advise removing it. Accessing it is more than likely slower than accessing the chip ram and if code and sample data are loaded into it, it's going to cripple playback.

[Karlos]

Hmmm...

Sounds like I'm going to have to break down my OS to the bear essentials if I'm going to remove that RAM.

Don't laugh, but for a while I used to use custom-rolled floppies that contained the absolute minimum system resources to run SS, which resided on the disk.

Sadly, I have recently entered into the wide world of unemployment, so I won't be able to afford any upgrades for a while. Not even a small little RAM expansion board. :/

Ah, that sucks. I hope it's not for long.

On the other hand, my A600 is in New Jersey waiting for Sloopy to recap it. I've already paid for the work so now I just need to wait for him to find the time. When that is back, I can pop my 030 back on it and go to town!

Assuming the recap job resolves the issues I was having with it.


Anyhow, thank you.

BTW, that PCMCIA RAM expansion really doesn't seem to slow things down.

What is the best software to test its speeds with?

Any old benchmark software, I expect. Having said that, if it's your experience that it isn't hampering things, then perhaps it's OK. My reason for assuming the opposite is the slow 16-bit interface. ISTR you can read at best around 2-3MB/s from it, versus about 7MB/s for Chip RAM.

Even just 2MB of trapdoor fast ram will typically double the speed of a stock A1200.

[Karlos]

Oh, now that's rich!!!

I was in a similar position. With 2MB of chip RAM, disabling the HD drive to reclaim the buffers was justification enough :-) It would boot straight into OMSS without opening WB or running anything that might steal precious RAM. Those were the days. I'd spend hours editing samples to make sure there was no unnecessary fat and use synthsounds, particularly for bass instruments.

I got my first accelerator because I wanted to be able to get more out of OctaMED SS (that and a few other apps I used). It's one of those bits of software that no matter how many more recent applications I try or on how many platforms, I always come back to.

[Karlos]

OctaMED has always been the main driving point behind all my upgrades too!

I began on a stock A500 with 1Mb of Chip (if memory serves correctly) and 2Mb Fast, all running off floppy. All that time making cheap Tekno tracks with OctaMED.

When you do get your A600 back, another interesting option is available to you. If you have a spare serial cable, you can link your A600 to your A1200 directly and run MidiIn on the 030/A600 as a 8/16-bit (14-bit via AHI) multitimbral sampler with that authentic Paula sound, triggered directly from OctaMED SS your A1200. This takes the mixing load right off your A1200. You can, of course, still use the 4 channels on that too, provided you have some way of mixing the combined output of each machine.

You can get some particularly satisfying results that way. One reason being that MidiIn's 16-bit sample playback is rather less restricted than OctaMED's.

While a serial cable is all you need for this (old MIDI is just standard serial data), if you use a MIDI interface to each machine in, you can obviously hook more stuff together in tandem. I used this topology for quite a while:

[Karlos]

Really?

How does all that work through a serial cable?

Well, I was editing my post to explain

To be clear, traditional MIDI is basically standard serial data. Amiga MIDI interfaces use optical isolation for safety when connecting to actual instruments, but if you are just going to control one Amiga pretending to be a MIDI device from another, a standard serial cable works just fine.

[Karlos]

I did not know that!

So if I set up two muffles, the one used for samples, would I then just configure each sample as a midi channel as well?

Yeah. However, MidiIn is multitimbral. Therefore, you can have it play back many samples over as many or as few MIDI channels as you wish. It can also do keyboard splits so you can create multisampled instruments (much better than the traditional 1 sample per octave) or drum kits and so on.

Obligatory screenshot: http://www.amiga.org/gallery/index.php?n=3232

In that particular case, I was playing a reproduction of the infamous mellotron "choir of the undead" from my controller keyboard. There were 12 16-bit AIFF samples in that set, taken over 3 octaves (one sample per three semitones, for A, C, D# and F#).

[Karlos]

I really need to freshen up on my musick vocabulary. You just lost me with part of that, but I think I get your meaning.

For the sake of clarity, I'll try and explain a bit better. As you already know, OMSS uses "Instruments" rather than samples as used by many contemporary trackers. In OMSS, An instrument can be a sample, synthsound or a MIDI output channel.

In your example video you showed how to use an external MIDI device from OMSS by defining successive Instrument slots in OMSS as output channels.

All GM compatible MIDI instruments will, by default, play normal instrument sounds on channels 1 to 9 and 11 to 16, with channel 10 playing different percussion instrument sounds for different notes.

MidiIn is a MIDI controlled software sample player. How it responds to MIDI input is pretty much up to you. The key points are that it is multitimbral (can play multiple different samples at the same time) and that it supports a variety of keyboard splits. Suppose you have couple of nice bass sounds, but they only sound decent in the low octave ranges. You may feel it's a bit of a waste to reserve a whole MIDI channel (as you only have 16) for each one. Instead, you'd like to play them all on channel 1. You could have them assigned to different MIDI preset numbers, but on OMSS, you'd either have to remember to send the MIDI preset change messages when switching them, or assign them to different OMSS instrument slots bound to the same channel. Both work, but can be a bit wasteful.

However, MidiIn will allow you create "keyboard splits", where you map different note ranges to different samples on the same input channel. For the scenario above, this is rather more convenient. You can play your first bass sound using octaves 1-3 and your second bass sound in octaves 3-5 and your third bass sound in octaves 5-7, all on the same MIDI channel and only using one Instrument slot in OMSS.

You can take the idea to it's logical conclusion and create keyboard splits where each note plays a different sample. That's great for creating custom drum kits.

Or you might have some sound libraries of real instruments that have been sampled at several different notes. The Amiga's traditional IFF instrument format supported a simple version in which you could have a discrete sample for each octave. Modern sample libraries tend to use a sample every few semitones. It was this that I had configured MidiIn for in the screenshot I linked. I had 12 samples taken over a 3 octave range from a real Mellotron, giving a sample every 4 semitones.

Consider just octave 3 for a moment. I had samples for C-3, D#3, F#3, A-3 and C-4. I split the keyboard around these notes as follows

B-2, C-3, C#3 -> use the C-3 sample
D-3, D#3, E-3 -> use the D#3 sample
F-3, F#3, G-3 -> use the F#3 sample
F#3, A-3, A#3 -> use the A-3 sample
B-3, C-4, C#4 -> use the C-4 sample

repeating this same pattern across several octaves, using a total of 12 such samples. All of which, were a single Instrument as far as OMSS was concerned.

BTW Muffles = Miggies. Damn iPod spell correction! :/

And yet, somehow I understood it to mean that all along