Ok, after giving it some thought, I decided to post this to see how much (and how far) we've come since Grand Daddy. This is an expandable list, so please present your thoughts or opinions on each tracker's classification (1st, 2nd, 3rd or 4th). I'd love to hear them, as well as learn more obscure trackers out there throughout history.
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1st Gen: First of its Kind
This marks the start of the tracker era. Primitive yet simple to work with, it serves the purpose of creating video-game music with its low filesize and respectable list of effects. Along the way, the base format .MOD got extended to 8 channels with 7-bit panning. Other (later) formats include .OKT, .MED and .STM, all of which are usually an extension of .MOD with a twist meant for its native trackers.
1st Gen trackers include:
Ultimate Soundtracker (Grand Daddy)
Protracker
NoiseTracker
Oktalyzer
OctaMED
Soundtracker Pro II
FastTracker
Scream Tracker
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2nd Gen: Upping the Ante
Trackers evolved into the 2nd Gen, where capabilities are expanded even more. Computers are faster and stronger...its the DOS age! Soundcards are all the rage: SB or GUS? The list of channels, effects and instruments are extended further than ever before. Formats that sprout from this gen are .S3M, .XM and .IT. While .XM expanded on .MOD's effects set, .S3M decided to modify it into its own and .IT followed suit.
2nd Gen trackers include:
FastTracker II
Scream Tracker 3
Impulse Tracker 2
Schism Tracker
CheeseTracker
Soundtracker
MilkyTracker
Protrekkr
MED Soundstudio
X-Tracker
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3rd Gen: Bridging the Gap
Developers realise that trackers can do more than what Impulse Tracker 2 could. They got inspired mainly by its New Note Actions (NNAs) and low-pass filter capability, to make their trackers VST-compatible! Not only that, the capabilities of the previous formats are also expanded further. Formats that are born from this gen include .MPTM, .SKM and .MT2. .MPTM follows behind .IT, while .SKM and .MT2 follow behind .XM.
3rd Gen trackers include:
OpenMPT
Sk@leTracker
BeRoTracker
MadTracker 2
MIDITracker
However, another group decided that keeping samples as its main source for instruments is not the way to go, and went another route: modular synthesis! By focusing on building instruments via "modules", they open up a new door for the tracking community to explore.
3rd Gen Modular trackers include:
Jeskola Buzz
Buzé
BuzzTrax
Psycle
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4th Gen: Bringing it to Commercialisation
This is the peak for trackers currently. Having GUI influences from DAWs, as well as the focus to bring tracking to a new paradigm, they spearhead the 4th Gen. Although focus on full compatibility with the previous formats are dropped, this proves to be more of a pro than a con as they are not restricted to just traditional concepts such as Ticks and Samples.
4th Gen trackers include:
Renoise
Radium
4th Gen Modular trackers includes:
Sunvox
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