Saturday, January 13, 2018

G-Storm Jupiter-6 VCF vs. Jove vs. SE 8106 modules

I get asked quite a bit what makes the Jupiter-6 VCF different from modules like the Jove by System-80, and the the Studio Electronics 8106. The Jove and 8106 circuits are a similar topology using readily available OTA chips, their PCBs are mass-produced, their boards are probably automated assembly for SMT parts. Mine uses the expensive/rare/original Roland OTAs, my PCBs are currently copper etched and tinned by hand, and fully assembled by hand as well. I'd love to build a Jove for myself, alas - no time (and PCBs are currently sold out). The demos of the Jove sound nice. I haven't checked out any demos of the 8106 yet, but everything SE makes is fantastic. I also suppose this is as good a time to announce my Jupiter-6 VCF is also undergoing a front panel re-design and will be very similar to my Delta VCF version 2.

Thursday, January 11, 2018

My Delta VCF Version 2 is Here!

My first video of 2018, I know it's been a while. I have been busy working on this little beauty! Today I introduce my Delta VCF version #2. You will remember the Delta VCF is my fully analog filter adaptation of the Korg Delta/Poly-61 synthesizers with the addition of a 2-Pole mode. My version #2 is exactly the same sound, functionality, and circuit as the version #1. It has a revised panel layout that makes the trimmers available from the front, is 12HP, and is now skiff-friendly. While we're at it, I audition some sound examples - starting with some PWM bass sweeps. I have trimmed the resonance for the module I am showing today so that it could self-resonate, I modulate that with an LFO. Audio recorded direct to Tascam DR-05, no effects or EQ added.

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Monday, December 18, 2017

The Keys To Huge Synthesizer Bass [Tonus VCF Demo #4]

Today in this demo I show some of the keys to getting huge bass sounds. I’m doing this on the Eurorack, but these ideas should work on most any synthesizer.
#1 Choose a quality low pass filter. I’m using my Tonus VCF module, a clone of the ARP 2600 filter. It’s a 4-pole low pass bass that uses a transistor ladder design similar to Moog.
#2 Cobble together as many oscillators as you can. Here, the Pittsburgh Synth Box wields a Tri, Saw, and Pulse along with a Sub-oscillato. Then I add another saw and square wave from the DNA Symbiotic Waves.
#3 For short basses use a punchy VCA/decay combo like the Bastl Skis. If you’re using a hardware synth, route a single envelope to affect the filter amount AND the amplitude at the same time.
#4 Modulate the filter with negative key tracking so that as you play higher on the keys, the higher notes will have reduced frequency cutoff. To do this I am sending the pitch CV to the signal inverter on my Pittsburgh Toolbox. Remember, a signal inverter just mirrors your signal across zero volts. For example, pitch CV goes from 0v to 5v. If you run that through an inverter, the output goes from 0v to -5v.
#5 Modulate the filter with a small amount of LFO to make your bass sound growl.
#6 Bass pads need a longer/slower Attack-Decay-Release envelope to evolve over time.
No effects used, audio recorded direct to Tascam DR-05

Wednesday, December 13, 2017

Happy Holidays from the studio

Quick update. Just added a couple more units of my Tonus VCF euro module adaptation of the ARP 2600 filter (4012 module) to my Reverb Store. They are now having the waterjet cut panels.

My Delta VCF module is sold out currently, I am taking this opportunity to re-visit the panel layout. I would like the jacks to be all at the bottom of the module like on the Tonus VCF. Using surface mount would make the builds go quicker as well. Hoping the Delta VCF will be available again before the year is out, we'll see. There will be a more official announcement and panel render when time comes.

Tuesday, December 5, 2017

Tonus VCF (X3) Filter Gets An Onslaught of CVs Eurorack Synthesizer

This being my THIRD video of my new Tonus VCF module, and therefore I must punish THREE of them, in a line up, with an onslaught of control voltages. For those living under a rock, Tonus VCF is my all-analog Eurorack adaptation of the righteous ARP 2600 filter - the early version 4012. Module #1 (left) is belting out a big ol' kick drum using self-resonance only. Module #2 (middle) is being grass fed whole grain digital bliss from the DNA Symbiotic Waves. Module #3 (right) is squeaking out stupid little astrodroid noises using only self-resonance. Varigate 4 and Beatstep Pro are micro-managing other things: Bastl Skis dual VCA, Pittsburgh Synthesizer Box, Toolbox Sample/Hold, 4MS RCD, sequential switch. All 3 filters mixed using my Infusor module. No filters were harmed in making this demo.

Wednesday, November 29, 2017

ARP 2600 Filter Adaptation - Tonus VCF Eurorack 4012 Module

G-Storm Electro is now on Facebook

G-Storm announces a new all-analog eurorack module, the Tonus VCF. For a long time I wanted a vintage ARP 2600 synthesizer. Then it dawned on me, all I really wanted was a faithful adaptation of the filter in my eurorack. I'm calling it the Tonus VCF on account that the Tonus ARP logo design was used on the earliest 2600s. Without any further adieu, let’s listen to the Tonus VCF in action!

Great care was taken to keep the Tonus VCF design as close to the original as possible including component selection and transistor pair matching. My modules are painstakingly hand-crafted in the USA in limited quantities. The first units are planned to be available on next week, but my parts suppliers are dealing w/ holiday shipping volumes this time of year. Asking price $200 USD, international shipment available. Full details and specs at Modular Grid.

Saturday, November 25, 2017

G-Storm Electro Now On Facebook

Check it out here and now. You know it's all about synthesizers, modular, and everything electronic music production. Like, comment, share, and review my hand-crafted modules as well.

Tuesday, November 21, 2017

Tonus VCF Module First Look [ARP 2600 4012 Filter Eurorack Adaptation]

Details are now available at Modular Grid. Yes it's real, and it's spectacular. Should be available for $200 usd in the next week or two on
In my previous video I showed a breadboard circuit of a classic analog synthesizer filter. The identity of the filter was left a mystery. Today in this video I not only reveal that it is a faithful Eurorack adaptation of the 4012 module from the early ARP 2600 synthesizers, you will get a sneak peek at my hand-crafted prototype design - the Tonus VCF - and hear it in action!

I jump right in and see how the Tonus VCF sounds by sending the resonance into self-oscillation. Be warned, demonstration of resonance self-oscillation can be shrill. Then I cut the resonance and send a sawtooth to the audio input, then a square wave, then a complex digital waveform from the Pittsburgh DNA Symbiotic Waves. After that I remove the audio inputs, return to pure resonance self-oscillation, and this time send the Sawtooth into the CV input to make the filter go berserk with some Filter FM. These are the kinds of sounds the ARP 2600 was known. Last I use an LFO and Sample-Hold as CV inputs. Audio recorded direct to Tascam DR-05, no effects.

Monday, November 20, 2017

Classic Filter Module Coming Soon - Photo

In my last video post I showed a breadboard circuit of a classic filter module. I have been hard at work developing this into a Eurorack module, a photo can be seen here. More info coming soon.