Portabellabz Synthi Card for Buchla 208

Published on Feb 4, 2019 Todd Barton

"The new EMS Synthi (licensed) Card by http://www.portabellabz.be
be sure to checkout these audio files for best sound http://www.portabellabz.be/SYNTHI_Car...
Great to have this onboard.! Wonderful sounds and timbres. I will be making more videos -- hope you enjoy this teaser."

And via Brian Comnes, spotted on Muffs:

"I'm happy to announce the release of a new Portbellabz card for Music Easel and 208 under EMS Cornwall license.

This card expands the Music Easel or 208 with original EMS Synthi A and VCS3 circuits : an oscillator that produces simultaneous square and triangle waveshapes with wide range and features useful modifications (synchronization, shape CV, hi/lo range) and a noise generator with variable colour, together with my acclaimed Random Voltage Generator modification module that expands many original EMS Synthi A, AKS and VCS3, unlike the 208's one, it's true random.
The inputs and outputs voltages are adapted to match the ones used in the 208.


It will be available in late February / early March, pre-built (€460 + shipping, Rogans and rear edge connector in option) or as a DIY PCB set (€130 shipped) like the 208 ToolBox.

The prices include a commission for Robin Wood at EMS, that is the same for each pre-built unit or PCB set sold.

It works with 208p, 208r (not rev1) and BEMI / Buchla USA Easels. The tracking can be set to 1V/oct, 1.2V/oct or 2V/oct (or other, but who wants that ? :lol: ).

A very few privileged persons were lucky enough to already test a prototype and enjoyed it. Thanks to them for keeping the secret.

Hopefully a demo video of the great Todd Barton should pop up soon, thanks in advance Todd.

In the meantime, here are some (very basic) demo of the card with my own 208.
All sounds are coming from the card except the CO modulation track (208's CO modulated by the card). A 218r was used to demonstrate tracking. It's a bit high in the lowest notes but this is fixed.

http://www.portabellabz.be/SYNTHI_Card_demos_mp3.zip

[b]Oscillator[/b]
- 100% analogue discrete components
- square and triangle outputs, blue bananas are full range outputs for modulation, red knobs are outputs to the mixer
- wide range from very slow LFO to ultrasonic, switchable hi/lo range with fine tuning
- tracking good on about 5 octaves via the 208's keyboard CV in
- variable frequency CV input with attenuverter via black banana
- variable shape CV input with attenuator via black banana
- variable sync input with attenuator via black banana

[b]Noise[/b]
- 100% analogue discrete components
- white banana is full range output for modulation
- red knob is output to the mixer
- variable colour

[b]Mixer[/b]
- tinijax out to feed the 208's preamp
- banana out for mixed modulation

[b]Random voltage generator[/b]
- available on the white banana - a mini slide switch behind the panel selects noise or random, this affects the white banana only, the noise is still available in the mixer when random is used
- clock input via the 208's inverter "to card" socket
- noise colour changes the random voltage

Bill Sequeira kindly did this nice overview. Thank you Bill.
The pictured card is a prototype, the production one will look very similar.

[img]http://www.portabellabz.be/images/PortabellabzSynthiCard.jpeg[/img]

Thanks for your interest and more soon."