Super Rare Vintage TBS-303 MKII Bassline Mono Synth (TB-303 clone+) SN 0399058 w/ Original Box

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via this auction

I've only seen one of these go up for sale back in 2007. Note the font under TBS in the upper left matches Sequential Circuits font.

Details form the listing: "What happens when you take the basic analog synthesis engine of Roland's classic TB-303 bassline, add MIDI control, and put it in a seriously heavy-duty tabletop housing?

You end up with TBS Musical Instruments TBS-303 MKII!

These are extremely rare. My guess is this is one of the very few of these that were ever sold to the US.

Per the creator's website--

The following list represents some of the main features of the TBS-303 MarkII :

Analogue circuitry is nearly equivalent to the original
Fully discrete oscillator and filter section
Build-in MIDI interface requires no external SYNC24 syncbox
Slides programmable via Note overlap
Accents programmable via MIDI note-ON velocity value (>100)
User selectable MIDI channel
Better that the original ; 'Heavy-duty' housing and professional potentiometers
The TBS-303 is on purpose build in a desktop type housing to make real time filter-control by hand easier.
Dimensions (WxHxD): 250 x 170 x 65mm

Additional cool features:

External audio input
Infinite accent button
Infinite slide/portamento button

Please check the website for additional info and audio samples.

The sound of this box is quite awesome. The top-mounted slide/accent buttons allow for additional realtime creativity. The external input lets you use this in ways that no original TB-303 can. Best of all, the MIDI implementation gives you all kinds of sequencing possibilities that you didn't have with the original.

Sure, you can make it sound just like a TB-303-- or you can use it in new and creative ways."