Zorx Electronics
Synthetic Sound Labs — Mini Sequencer Model 1650

Synthetic Sound Labs — Mini Sequencer Model 1650

by John L Rice

There is a well-known aphorism among modular synthesists that states, “You can never have too many VCAs!”, and while I might tend to agree, in my mind a more important pearl of wisdom is, “You can never have too many sequencers!” On a basic and obvious level, sequencers provide a means of automatically stepping through a series of predetermined voltages. Some sequencers just produce fixed high/low voltages which are most often used to trigger on/off events in other modules, while others can produce variable voltages which are most often used to coax melodies and bass lines from oscillators. Many sequencers can produce both fixed and variable voltages in parallel per each step. Things tend to get interesting when you have two or more sequencers at the same time being processed and cross interacting with each other like having them transpose, start, stop, reset, set position, and/or clock each other. Creating greater complexity out of many simpler elements is what modular synthesis is all about, so I’ll say it again: “You can never have too many sequencers!”

The SSL Model 1650 Mini Sequencer is an exciting and unique offering as there are no other 5U format sequencers currently available that are as powerful with a similar small size and low-price. It began life as a brilliant promotional item created by Scott Rise of Division 6 during Knobcon 2016 when he handed out little business card sized printed circuit boards to folks who were in attendance. With the instructions on his website it could be turned into an actual working sequencer and it has grown in popularity over the last few years with multiple versions existing, including complete kits with stand-alone case, a dual Eurorack module, and of course, the collaboration with Doug Slocum at SSL to create this new 5U Mini Sequencer!

On a basic level, the Synthetic Sound Labs Mini Sequencer is a 16 step CV/Gate sequencer, but once you get past spending long hours gazing at its gorgeous retro-modern panel [I had the privilege of discussing the panel layout and features with Doug at SSL and some of my ideas made it into production, so of course I might be slightly biased!] you may be surprised at all of the power that lies waiting underneath its oh-so-handsome hood!

The most obvious difference between this and just about any other sequencer is that instead of being programmed with a separate knob and switch for each step, or having a menu screen manipulated with just a couple knobs and switches, this sequencer is programmed entirely using a series of square clicky buttons with LEDs in them, like the kind that were used in some of the cool iconic synths and drum machines of the late 1970’s and early 1980’s. The two yellow Step buttons at the upper right select which step is to be programmed, and the combination of the blue Octave buttons on the upper left with the black and white ‘keyboard‘ buttons near the middle assign the desired Note within the available 5 octave range. The Step buttons also have a dual purpose and are used to change the speed of the internal clock.

There are the additional options of Accent, Rest, and Loop that can be assigned to each step with the three gray buttons, but a step can only have one assignment—except for Accent. Accent can be additionally assigned to any step regardless of other assignments and this is a useful feature, particularly for steps with a Note and sometimes even a Rest because Accents fire a gate out of a dedicated jack. Rest will prevent a gate from being fired but it will also cause the voltage from the previous step to be maintained, effectively tying the notes together. Loop will jump the position back to step one and the sequence will continue running.

The remaining two buttons are the green Run/Pause and red Reset, both of which perform their named tasks but do need additional explanation. Run/Pause will run or pause the sequence from or at its current position if there is an active clock pulse available, and when tapped, Reset will not only set the current position to step number one, but also stop the sequence from running. Additionally, when held down for about three seconds, the Reset button will force a ‘warm reboot’ of the sequencer and this is necessary if you want to use the internal clock after an external clock has been used. When the sequencer is paused, tapping the Reset button will toggle the sequencer between program and play modes, indicated by the current step LED being steady on or flashing, respectively. Play mode allows the sequencer to be played like a micro-controller without affecting any of the values assigned to the steps, and besides being fun, this is useful for sending transpose voltages to another sequencer of for live jamming.

While normally self explanatory, the jacks found at the bottom of the module deserve some explanation. You will notice that the Clock In, Gate Out, and CV Out jacks are in pairs. This is simply a space saving convenience feature for chaining multiple sequencers and/or for feeding two VCOs or parallel voices without the need of an external multiple. The End Out jack sends a gate on the last step of the sequence and the Start In jack needs to receive a gate to know when to start another run from the beginning. These jacks are internally connected so that the sequence continually loops when run. Inserting a plug into the End Out jack does not break the connection, so its output can be used elsewhere, like as a 1 to loop-length clock divider, but there are other uses also. If you happen to have two SSL Mini Sequencers you can cross patch these two jacks and the two sequencers will run in series, effectively creating an up to 32 step sequencer. Also, as an easy workaround to the lack of a reset input jack, just patch these two points to a multiple along with your reset signal source.

There a couple of things I wish this sequencer had:

Fixed 12 tone chromatic tuning

Assigned step values cannot be changed while running

Internal clock speed can only be set when running and speed change is unintuitive, left is faster/right is slower

Reset stops sequencer and sets CV output to zero volts

No dedicated reset input jack

Forward direction only, no reverse, ping-pong or random

I have had a great time being inspired by the Synthetic Sound Labs Mini Sequencer, and no matter which of my various setups large or small I’ve had it in, I recommend to anyone in the5U market for a sequencer to give it serious consideration.

To see more of, watch my Exploring The SSL 1650 Mini Sequencer YouTube video that can be found at:

2 MU +15V 16mA

Price: $295