SQ16 is a simple hardware sequencer made by German company MAM (Music And More). It offers 16 channel mono-timbral channels. 13 of these channels are for drumsounds only (each step always triggers the same note), the other 3 channels are note-tracks (each step can contain different notes).
It stores all data (64 patterns, 8 songs, chains and all conifiguration data) in so-called 'Blocks'. It offers 8 of those Blocks. Only one Block can be accessed at a time, so you cannot combine patterns from one block with a pattern that was stored in a different block. It is possible to dump data to its MIDI port by the way.
It was mainly created to make it easy to create drumparts (this is also mentioned in the manual), but I think adding the three note tracks was a very good idea. Each track features an Accent on/off track for each step. You cannot program velocity-values for each individual step, instead you can program only two different values. Each step always uses one of those two values (this depends on whether the Accent-step was turned on or off for a step). Keep in mind that you can assign two values individually for each track though.
The SQ16 only outputs note data (and MIDI-click data if you wish). It does not support any controllers (this was intentional according to the manual) and it also does not send or recieve program-/bankchanges.
The Rotate feature is very hard to explain. I have not really messed with it yet. The manual simply says "This function generates rhythmical variations by changing the Step Play Position; the original rhythm of the pattern (instrument tracks and note tracks) however remains unchanged.", but the examples are quite hard to follow IMHO. Each and every review I have read (SOS, FM...) mentions that it is extremely difficult to understand this section.
Lengths/duration of notes can be 100% (one step) or 50% (half step). Note-tracks also have a Hold on/off track though for each step. Patterns can have a steplength of 1/1, 1/2, 1/4, 1/8, 1/16 and 1/32, but patterns always have a length of 16 steps. You can manually set the latest step of a pattern (but not for each track individually as far as I know).
All by all, the MAM SQ16 may look like a very limited sequencer by today standards. I must say that I love to play with it though, probably because *of* its limitations. I am very happy with it. I love to combine the SQ16 with a softsequencer (I personally record SQ16's MIDI output in Cubase VST).
The first few days it seems quite hard to operate, but after a short time it will become second nature (well, if you exclude the Rotate-feature that is). It takes some time to master though.
I think the main thing that the SQ16 is missing is a Groove Quantize feature. It always sounds very strict. I have heard that MAM may be working on a new sequencer, and if this is the case I will recommend them to include support for sending MIDI-controllers individual for each step, like Seq303 software-sequencer could.
Released: 2000 | 
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