Who becomes silverware first? - 10 minute LFO filter sweep and semi-generative Eurorack jam

video upload by thesrabbit

"This sonic experiment was inspired by the Dreadbox Erebus LFO having a whopping 10-minute long cycle time. Therefore, I thought it might be fun to run that LFO into every single filter I have with a CV input, including big analog polys with a VCF control input on the back intended for expression pedals. The honorary VCFs include: 2x Roland System-500 521, G-Storm Electro SH-2 and SH-5, Dreadbox Erebus, Oberheim OB-X8 (OB-X SEM LP mode), Sequential/Oberheim OB-6, Roland Juno-6.

Interestingly the filters on the big polys don't open all the way. I assume this has something to do with the inputs being calibrated for expression pedals rather than Eurorack CV. According to my oscilloscope, the Erebus LFO range is -5v and +5v. This is pretty typical for Eurorack. I set the cutoff at about 50% for all the filter modules. This seemed to work perfectly. But I was not able to do that with the polys. With the cutoff at 50%, the filters would open up all the way, but they wouldn't close nearly enough. I had to bring the cutoff completely down, and as a result, the filters on the polys wouldn't open up all the way. I did alternate takes where I walked around and tried to smoothly nudge each one up in order to get the filters fully open, but that was a disaster. In retrospect, I could have set up a one-shot MIDI LFO to do this and triggered it once at the right moment, but I already had enough things to worry about.

One of my audio interfaces is dead or dying, and it keeps ruining takes and sometimes crashes Logic. I finally turned it off and went with my lone Focusrite Scarlett 8i6, which has always been solid. But now I had an extra synth without an input and I wanted to have the polys on their own tracks so that I could blend them in with the Eurorack stuff to taste. And there's no possible way I could overdub since the whole point is to have one LFO sweeping all of the filters at the same time. I ended up resorting to an old 1989 JVC cassette deck to record the OB-6. So that shot at the opening of the video is legit. There's such a big wall of sound here that it's impossible to tell if it ended up adding any saturation. It definitely added some hiss and crackles but that's fine in this context. The cassette itself is ancient, cheap consumer grade, 60 minutes per side. I ended up recording over some 90's black metal that had been there since, well, the 90's.

To add to the grit and grime, I intentionally ran the filters from the Eurorack straight into the audio interface, bypassing the typical flow through VCAs. Ok, fine, I totally forgot about the VCAs, but it sounded extra dirty, so I didn't stress out too much. I certainly wasn't going to power everything back on, tune everything up and do another take because of it.

Obviously when the filters are closed or nearly closed for several minutes, there needs to be something to fill that gap. That's where the generative stuff comes in. There's 3 different sample and hold circuits feeding different things, including back into themselves in one case. Some voltage is running through different logic gates in conjunction with other, steady LFOs. Since I'm out of filters, the sound consists of pink noise through a VCA, triggered at random by a very short decay envelope. This runs into a recovery tape delay module, that gives sort of a slapback effect.Then there's a single oscillator, pitch controlled by another S/H circuit run through a quantizer and then running into the spring reverb tank. It's also triggered by the same random voltages triggering the noise hits. Then there's the Mutable Instruments Plaits, making the plinky plonky sounds, again everything triggered at random. It's running into the majestic Calsynth Typhoon.

The last thing to note is that the Erebus LFO also acts like an automated fader to increase and decrease the level of the VCA where all the rhythmic sounds are running through. I simply inverted the signal of the LFO output to do this. As the filters open up, the VCA level diminishes. When the filters fully close, the VCA level increases to maximum.

Last last thing. That knob twisting near the beginning isn't for sci-fi FX, though that's an added bonus. I was simply trying to get the LFO back to its "starting position." I didn't quite succeed. I don't believe the Erebus has any sort of LFO triggering mechanism to help with this. All good though.

FX: Audiothingies DoctorA delay and reverb, Boss DM-101 delay

No post processing other than a 30Hz low cut and slight limiting on the master"

G-Storm Electro SH-5 VCF

Note: Auction links are affiliate links for which the site may be compensated.

via this auction

"Amazing filter clone of the famous Roland SH-5 synthesizer! Bought a couple months ago from the G-Man along with some other stuff, everything he makes is excellent. I really like the sound and functions of this dual filter on its own, but I’m not sure it fits into my overall sounds and the overall tone of my half dozen other filters, so I’m listing it, but keeping his ARP 2600 filter clone!"

Check out demos in previous posts here.

SH5-VCF: Beauty & Terror [Demo #3] (no jibber-jabber)

video upload by gstormelectro

G-STORM ELECTRO SH5-VCF posts

http://reverb.com/shop/gstormelectro


"Audio + Video by G-Storm Electro c. 2021

Some Darkscape Eurorack patches featuring the SH5-VCF.
Exploring some near-oscillation resonance sounds.
And frequency modulation of the VCF which this diode filter is so good at.
This time around using Big Sky Reverb and Timefactor Delay.
If you want to hear the naked filter alone the first two demos I made were bone dry no effects :D

I used different colored patch cables, so maybe you can glean what is going on.
If there are questions about that go ahead and pepper me in the comments.

SH5-VCF is all-analog eurorack adaptation of the Roland SH-5 Synthesizer Filter and Mixer.

As per usual, listening w/ headphones or quality monitors is the best audio experience.
Watch your levels, this is a filter demo w/ some resonance ahead.
Be sure to check out SH5-VCF Demo 02 to see how I made the patches in this video!

Oscillators | Pittsburgh Primary Oscillator B, Cre8audioCapt'n Big-O
Modulations | Batumi, 2xADSR, Delta Soundlabs Mobula Ring Mod
Control + Sequencing | Keystep Pro"

G-Storm Electro Introduces Roland SH5-VCF Dual Filter Eurorack Module Adaptation

video upload by gstormelectro

SH5-VCF Dual Filter Patches + Sounds [Demo #2]

video upload by

"In this video I will show some cool patches with SH5-VCF Dual Filter.
As per usual, listening w/ headphones or quality monitors is the best audio experience.
Watch your levels, this is a filter demo w/ some resonance ahead.


Check my Reverb store for SH5-VCF, 101-VCO, 2xVCA, 2xADSR availability

Currently I only sell exclusively on Reverb, I hope one day to sell in stores outside the USA.

Timestamps
0:00 Sounds and Intro

0:16 Patch 1 | Fat Liquid Bass
2:44 Patch 2 | Series Cascading the Dual Filters
3:01 Patch 3 | Evolving Sequence
3:47 Patch 4 | Analog Percussion
5:20 Patch 5 | Supersaw! Unison Stack
6:33 Patch 6 | Complex Analog Thing

Oscillator | 101-VCO
Modulations | Batumi, 2xADSR
Control + Sequencing | Keystep Pro
No added effects, EQ, Compression, nor other post-processing."

via this listing

"Time to get a little more serious.

SH5-VCF is an all analog Eurorack adaptation of the Roland SH-5 mixer and Dual Filter. There are no filters-on-a-chip here. The SH5-VCF uses all discrete components and quality op-amps to work its special mojo. Like on the original, the Low Pass circuit is comprised of open-collector matched transistor pairs arranged in a diode ladder configuration. The lack of temperature compensation was also respected, so while the resonance can self-oscillate the v/oct keyboard tracking is about 3 octaves at best. This same configuration used in the Roland SH-1000 and the earlier System 100 (not 100m).

The Dual Filters: VCF + BPF
| VCF | The VCF (Voltage Controlled Filter) comprises one HP (High Pass) and one LP (Low Pass) circuit in series. VCF Select switch can choose 1) HP, 2) LP, or 3) BP (Band-Pass) configuration. Due to the unique design, the HP resonance is actually derived by overdriving the LP circuit.
| BPF | The dedicated BPF (Band Pass Filter) has its own discrete circuit distinct and apart from the VCF. The original BPF circuit has been respected, but greatly expanded upon using a proprietary voltage controlled feedback path to enable frequency control via external signals. This feature wasn’t available on the original design. The original did not have a buffered output jack for the BPF neither, as the SH5-VCF does. The BPF Level attenuator will affect the main output only.

The MIXER
There are four audio signal inputs, each with its own fader pot and filter routing switch. Each routing switch can send each audio line to either VCF, BPF, or both VCF + BPF.

The 3 CV MODULATIONS – Choose Wisely
Incoming CV signals can be used to modulate any filter frequency cutoff. Signals can be up to +/- 10Vpp DC polar or AC bi-polar at the inputs.
| CV1 | has inverting and non-inverting behavior where zero is at 12:00.
| CV2 | has non-inverting behavior for both filters, and inverting available to VCF only
| KB | is a non-inverting V/OCT Keyboard Tracking control available to both the VCF and BPF, typically a Keyboard Voltage – but can be any kind of polar or bi-polar signal.

A Eurorack power connection ribbon cable is included. To get the most out of the filter experience follow your filter with a VCA. The filters require startup voltages on the low end to avoid audible thump, so there will be sub-frequency audio seepage. A post-filter VCA (sold separately) is recommended to gate the filter. Be sure to check out the G-Storm Electro 2xVCA when available.

The SH5-VCF pairs well with (sold separately)…
GSE 101-VCO + 101E output expander
GSE 2xVCA
GSE 2xADSR
Xaoc Batumi Quad LFO

Specs
Width | 16HP
Depth | 35mm
Weight | 6.3 oz
Inputs | 4 audio, 3 control voltage
Outputs | 1 main output, 1 BPF output
CURRENT DEMANDS (measured)
+12V: 48mA
-12V: 48mA
+5V: 0V *not used*"

G-Storm Electro Reverb Shop