MAM MB 33 / MB 33 mkII

MAM MB-33 Image

MB 33

The MB 33 is a rack-mounted TB-303 clone released in the mid-nineties by German synth maker MAM (Music And More). It's basically identical to the Freebass 383 (which had a different front-panel design). It is a true analog monophonic bass synthesizer with MIDI implementation so you can create 303-like bass lines from your sequencer. Its single VCO offers the same two basic waveforms as the TB-303: a sawtooth and square wave. But in the MB 33 they can be mixed together for a more interesting tone than the 303 could originally produce.

Additional knobs control the VCO tuning, filter frequency cutoff, resonance, envelope mod amount, envelope decay time and accent intensity - the same controls found on the TB-303! The 24dB lowpass filter can also produce the characteristic sound of the 18 dB filter used in the original 303. There's also an auto-slide function (4 octave range) for producing those 303-style slides and a separate input for filtering external signals through it. Unfortunately there is no program storage.

MAM MB-33 II Image

MB 33 mkII

The MB 33 mkII (pictured above) released in 1998 adds a few more features. The 24dB filter has been replaced by an 18dB filter just like the original TB-303 used. A new sub-oscillator was added and can be mixed with the other two waveforms for even meatier mono-bass sounds. A new distortion effect is also present and can be dialed-in to dirty things up - sounds great when resonated at high frequency cut-offs! MIDI can send/receive controls for the cutoff, resonance, ENV mod, accent, decay, distortion, and autoslide on/off.

Whereas the original MB 33 and Freebass 383 before it sounded very much the same as the TB-303, the newer MB 33 mkII adds even more possibilities for creating your own unique 303-like sounds - and at a fraction the cost of an original 303!

Lookup MAM MB 33 / MB 33 mkII Prices

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12 Visitor comments
February 2, 2014 @ 3:56 am
Bought the original MB33 new and loved it. Sent it off to MAM and thy put a knob in for controlling the portamento rate, sonce its way too long for authentic 303. Sold it a few years ago and now I´m sad. Thing is that I just found a nice mkII and it has the same problem. I don't think MAM is around anymore to help me. My hope is that some of you know what the pots inside of the MB does. I would like to tweak the porta down a little. There are lots of little potentiometers inside.
August 14, 2012 @ 5:11 pm
Hello i have had a MB33 MK 11 for about 6 years now i paid £100 and it is still mint .Personaly i cant tell the differance between a real 303 and the mb in full swing .it has never responded to more than 3 octaves on the keyboard (Not a Problem) ,the manual says 4 octaves (49 keys i presume)
Has anbody else found this ?
Brian One
October 19, 2011 @ 9:25 pm
Cant believe how cheap these are going (the mk2 model) considering how good they are. 85% 303 sound with 200% of the sound capabilities, midi cc for most parameters, small footprint & knobs per function. win win win!
May 10, 2011 @ 5:33 am
IT IS NOT A re-packaged Freebass 383. The FAT Freebass is a repack made to Turnkey UK by MAM! MAM germany is the original firm behind all MAM and Freebass items.
April 24, 2011 @ 2:54 am
picked one up about 2 years ago... I have really only used it for bass... which it is great for indeed.The sub octave mix and env PWM give it some variety on timbre. With the filter open and resonance up sounds tweezy doesn't give the same squelch as a tb303 even with that screwdriver adjustment, but on anything from lows to mids I can get it to do something I'll agree with. The distortion is ok up to about 50%, then it starts stealing all the low end grunt, but in bits and pieces it helps sculpt the sound. Glad I own it as it does have its own character.
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  • Check Price
  • The link above will take you to an eBay search for this synth to see active listings. If you don't find it there, try looking in our forum marketplace or post a wanted classified.
  • Specifications
  • Polyphony - Monophonic
  • Oscillators - 1 VCO with mixable sawtooth and square waveforms.
    MK II adds a sub-oscillator
  • LFO - None
  • Filter - MB 33: 24 dB/oct lowpass filter (MK II uses an 18 dB/oct filter) with cutoff-frequency, resonance, ENV-modulation controls
  • VCA - Decay-time (200 ms - 2,5 sec.) VCA separate ENV-generator with non controllable voltage assignment. ACCENT pot for accent-intensity; can be activated at velocity parameters greater than 120.
  • Keyboard - None
  • Memory - None
  • Control - MIDI, CV IN to VCF
  • Date Produced - 1996 (MB 33)
    1998 (MB 33 mkII)
  • Resources & Credits
  • Images from MAM.

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