next! SPACEBASS 3.3 With Mods

via Circuitbenders.co.uk
Click through for demos. Details on the mods captured for the archives:

"This is the 'next! SPACEBASS 3.3' version (the exclaimation mark remains a mystery), which is exceptionally rare. As far as we know, this version was only ever available very briefly in the US and this is the only one we have ever seen in Europe. Most versions found in the US appear to be imported Freebass' or MB33's, so we'd suspect that very few of these models were ever produced.

Our mods add 5 switches, 2 knobs and a jack input round the back to allow a whole extra smorgasbord of sonic mayhem. A veritable 3 course breakfast of orgasmic analogue delight! Something along those lines anyway :) .

THE MODS INCLUDE:

VCO On/Off Switch: One of the most annoying problems with the Spacebass is the way that the VCO is removed from the mix when a jack is plugged into the VCF input. This makes it impossible to stick it in a rack without spending half your time reaching round the back trying to find the VCF in socket. We have solved this problem by preventing the VCO being automatically cut when a jack is inserted, and instead adding a VCO on/off switch to remove it manually if you chose to. This means you can now permanently wire the VCF input into a patchbay.

VCO Drive: In our experience onboard distortions tend to be rubbish and you'd do a much better job driving an acid line through an analogue mixer or a RAT distortion pedal so this isn't really a super distortion but rather just drives the VCO into the filter to add a little more bite and dirt to the acid sound.

Resonance Boost Switch: Another annoying issue with these machines is that the resonance never reaches self oscillation (but then neither did the TB303) and also drops off considerably when the cutoff is over 3/4 of the way up. We've solved this problem by adding the resonance boost switch. With this switch activated the filter starts to squeal with the resonance about halfway up and then just screams at any higher settings.

Filter Lock Switch: On a standard Spacebass if you want to use the VCF input to filter external audio signals you have to trigger the filter and VCA envelope using a midi note message, the filter then closes until it recieves another midi trigger. This also means that by default the external signal will have the VCA and VCF envelope applied to it, so regardless of what kind of sound the external signal actually is, it will have a TB303 filter and amp envelope. While this can be useful on some occassions, most of the time its just annoying so what this mod does is add a switch that locks the filter and VCA open at a constant level without having to use any midi input. The filter can then be adjusted in realtime using the cufoff and resonance knobs.

VCF FM Controls: These consist of three controls and a jack input. Essentially VCF FM allows you to modulate the filter cutoff at audio frequencies to create all kinds of clanging cross modulation and bizarre alien splatters & sweeps. This effect works best with the resonance cranked up into self oscillation which is where the resonance boost mod comes into play. The FM controls allow you to select one of four sources for the FM signal. The first is the normal VCF input socket round the back. This means you can run a sound through the filter section, but also use that sound to modulate the filter cutoff at audio frequencies at the same time. The second source is a new FM input jack on the back of the rack. Using this source allows you to run a sound through the filter from the VCF input, and at the same time modulate the filter cutoff with an entirely independent sound source at the FM in jack. The main VCO signal can be added to the mix at any time. The remaining two sources are the sawtooth and square wave signal from the main oscillator. These can be selected as sources completely independently of the setting on the VCO wave knob.

The last controls in the FM section are the VCF FM on/off switch, which, in line with common convention turns the VCF FM effect on and off, and the FM amount knob. This final knob controls how much the source signal modulates the filter cutoff.

VCF CV Input: One of the major drawbacks of these machines is the lack of any MIDI knob control. We have added a 1/4" jack round the back of the machine that will accept an external CV to control the filter cutoff. It is set up the input so that it will accept a CV input of 0-5V which will allow you control over at least 95% of the filter cutoff range. Certainly more than enough for a rushing acid builder!

This mod also adds a switch on the front to toggle between internal and external cutoff control.

Accent LED: The Spacebass triggers an accent on a note when its midi velocity is 120 or more. This a simple but useful mod that gives you an extra LED that flashes whenever the accent is triggered, regardless of the setting of the accent amount knob. This can be handy when programming sequences via midi, or in a live performance or recording situation where it might be useful to know where the accents are without turning up the knob and hearing the effect. We also probably shouldn't forget the main reason for this extra LED, i.e. extra flashing lights are always welcome on anyones rack!

The LED only flashes when an accent would actually be audible with the knob turned up. As with a real TB303, on the Spacebass you can put a glide/portamento on a note so that it slides/bends into the next note without the envelope retriggering. If you put an accent on the note being slid into (is slid a word?), then with the envelope decay turned down, you won't hear the accent peak and the LED won't flash. As you turn the decay up then the accent will start to produce a kind of slow attack punch in the bending note, and the LED will flash to show an audible accent is present. It also flashes on normally accented notes

We've also added a power switch so you don't have to keep unplugging the thing, and swapped the standard red power and midi activity LED's with some orange ones to match the front panel graphics..."