macbeth studio systems x-series 'backend' filter price : $1,295.00

this module comprises of an 3 way audio input mixer, a control voltage input mixer, a 24db/octave voltage controlled filter with 4 tapped outputs, 2 voltage controlled amplifiers and control envelope generators. bar one 'buffer' ic- the circuits are all discrete transistor, resistor and capacitor based. just like the x-series dual oscillator- the resistors are all half watt carbon types and the capacitors are a mix of ceramic/mylar types. the result of this design is an extremely warm and vibrant module. from the bass end up- the sound is consistently clean but full...this is down to pure discrete transistor design and pcb layout.

a response switch sends the filter output into the first vca and the choices in the final model are 6/12/18 and classic 24db/octave responses. a second vca can be externally controlled for the final output and lends itself to am applications and other voltage controlled volume applications.

as can be seen- all four responses can be tapped out via jack sockets and these are pre- vca outputs. each envelope generator provides control outputs- the vcf eg sports two outputs- both positive and negative. there is also a dual switch- providing both momentary trigger and hold.

why 'backend'? effectively this combo module is like the backend of a classic analogue synthesizer. it has all the functionality of a full synth but just lacks the sound sources- all this in a compact 42hp 3u size!

i have recorded some deomos using this protype module and you can here it in action with the x-series dual oscillator...

audio samples:
here we have 2 identical analogue oscillators. these have been designed optimally as tone sources although they lend themselves to low frequency applications too. these are 'classic' designs. they both feature 10 turn wirewound frequency potentiometers, i used them to great effect on the m3x synthesizer- they make accurate tuning simple and quick and they are also great fun to play with! i've included a 5 octave range switch for easy transposition of pitch.

there are 6 waveform output sockets on each of the oscillators-those being: sawtooth, ramp, fixed square, rectangular or pulse ( this waveform can be shaped manually or by a control voltage source), triangular and sinusoidal.

as said, i see the dual oscillator as a primary sound source- so i thought that it would neat to include both a ring modulator and a noise generator to complete this combo. the ring modulator is designed around the mc1496 balanced modulator ic which was commonly used as a ring modulator found in many early synthesizers. this is not an 'analogue multiplier' ic. it sounds fantastic and vintage!

sample one
sample two

the noise generator supplies any variation between clean white noise and rumbling pink.

sample two

there are facilities for both logarithmic and linear control of each oscillator as well as internal cross modulation and glide control. oscillator 2 has its sine waveform normalised into the oscillator 1 linear fm input control. oscillator 2 can be hard synched to oscillator 1 for screaming lead solos or sequences! provision has also been made for each oscillator to be synched to external sources.

dual oscillator linear cross modulation
dual oscillator logarithmic cross modulation 1
dual oscillator cross logarithmic cross modulation 2
dual oscillator cross modulation and ring modulation

if you liked the sound of the m3x and m5/n series- you'll love these...now! click on the links below for some audio tracks!

not that old skeleton again!
harrys march of obsession
x-series 1
groovy jazz!
slippery squares
brit prog from hell
endgame