Toppobrillo TWF Update

Some more examples of the wonderful Toppobrillo Triple Wave Folder.



Self-running patch comprising two VCOs & VCAs, Maths & Wogglebug. One VCO is folded, the other modulates the TWF's Bias, WB is triggered by Maths' EOR, stepped out to pitch, envelope slopes and WB clock.

Recorded in response to Rechner7's Stockhausen-esque Noise Ring/ Pressure Points patch.

Wavefolders respond to dynamic changes, so I gated both the carrier and modulator before sending them to the TWF. This can have a dramatic effect and this patch would not have sounded the same had I gated the output post folding.

This is an example of using the TWF to achieve linear-FM-like sounds: tbtwf_doublebass

Again, the VCO was first sent to a VCA. An envelope modules the bias, manual tweaks to envelope times and DC offset. Pure sine first, then folded.

This sort of sound is normally quite tricky to achieve via analogue FM, because of phase and tracking issues.

Here's an evolving sound featuring a sine wave some light envelope modulation of bias and manual tweaks: tbtwf_evolve

The Triple Wave Folder has so many sweet-spots for this kind of tonal shaping and the output is clean enough so you don't need further filtering.

Lastly, here's an example of the TWF's saw to sine function: tbtwf_saw2sine and a PDF with software 'scope pictures.

As you can hear, it does a great job. I asked Josh about the rounding of the saw evident in the 'scope shot and he confirmed that this is normal. He also explained how he achieved the panning effect in his demo: the resulting sine is 90 degrees out of phase so all you need is a multi-output LFO/ oscillator. Thanks Josh!

PotD - Toppo Banjo & the Wonky Beat

Two patches/ applications featuring Toppobrillo's Triple Wavefolder: first as a traditional audio waveform multiplier, then processing an LFO to generate syncopated rhythms.

Toppo Banjo

Although the TWF is capable of creating more extreme sounds, especially when fed with polyphonic or FM'd material, in this first recording I've kept the settings fairly tame.

For the plucked banjo sound two stages of the TWF processed a single sine wave which was then filtered by a Wiard/ Malekko Borg. The bias was modulated with an envelope. The guitar sound was similar, with the exception that I modulated the DC offset with an LFO. The Hammond/ Leslie-like sound was the result of three stages folding an exp. FM sound from a Cwejman VCO-2RM, an oscillator the TWF seems to love.

In this second example I used the TWF to multiply an LFO to mess with an otherwise straight rhythm:

BeatFolder

The kick drum is triggered by the pulse out of a Doepfer A-147 VCLFO, the FM click sound by the folded signal and the FM klonk by a subdivision of the same (A-160). In the first 40 seconds I adjusted the bias settings of the three folding stages, thereafter I altered the DC offset. This was a lot of fun and the results are certainly useable.

The Toppobrillo Triple Wavefolder has been a revelation to me - despite having built my own CGS Lockhart Wavefolder and tried Doepfer's A-137 and the Bananalogue/ Serge WVX, I never quite 'got' wavefolding/ multiplying. The Toppo sounds fantastic - to my ears, the best of the bunch - and its open nature makes it a flexible tool: you could, for example, tap the output at stage two, send it to a resonant filter it and then return it to stage three for some final folding. I managed to coax subtle plucked harp sounds through to aggressive sync-like 'digital' basses from this module, all with minimal fuss. Its taken me a while to cotton on, but the Toppo has opened my ears to wavefolding and got me inspired.

Thanks to Herr Schulz at Schneiders for his almost missionary zeal in recommending the TWF!

Patch Tips #27 - An FM Equivalent

An analogue take on digital FM featuring the Toppobrillo Triple Wavefolder.



Today's Patch Tip is inspired by MitchXI's description of a digital implementation of FM:

" ... in a yamaha style set-up, an oscillator is simply a ramp that goes from zero to one for every cycle - a phase accumulator - that gets fed into a lookup table that converts zero to one values into a sine wave. if you add a second oscillator's sine output to the ramp wave before the sine wave function, you get an fm equivalent ... to have an fm modulation relationship, you simply add the output of one oscillator into the other oscillator's sine wave function. the only digital computations that need to happen are addition, multiplication (for mod index/amount), and a table lookup."

If, like me, you feel digital is cheating, here's an analogue solution:

For the look-up table we can use the TWF's saw-to-sine function. Patch your saw (carrier) to the TWF via a mixer and trim the bias on a single channel to achieve a clean sine. Apply your modulator via a VCA or directly to the mixer and trim the amount of 'FM' to taste. In this example I used two VCOs/ two TWF channels and one modulator. I start with just the one voice which I pan left when I introduce the second voice:

twf-fm-equivalent.mp3

At high modulator frequencies the result is pretty good. Because the saw-to-sine converter is analogue, it is sensitive to variations in amplitude and DC offsets. And, like Phase Modulation, this method has it's limits: If the modulator is too slow the 'FM' effect will be negligible.

This patch won't replace your thru-zero FM or phase modulation VCO - the maximum possible index seems similar to standard linear FM. But if your oscillators only have exponential inputs, the Triple Wave Folder offers another unexpected method of dynamically changing the colour of your sound.

Patch of the Day - Lagtyme

Featuring the Toppobrillo Sport Modulator as VC divider and Triple Wave Folder as VC Multiplier.



Today's PotD is based on the 'VC divider' patch with the added twist of a multiplied pulse train courtesy of the TWF. Mult your clock source to four destinations: the TWF, Env1, SM1 S/H and SM2 S/H. Set both sections of the SM to cycle in 'hold' mode, send the output to two VCOs (in this case for pitch and PWM) and the End Out to envelopes 2 & 3. Take the TWF's pulse output to trigger a fourth envelope. In the recording, the first sound you hear is paced by the source clock, the two VCOs by the divisions generated by the SM and the hi-hat by the TWF stream.

You might not want the pitch changes generated by patching the SM's outs to the VCOs, but in this case it allowed me to generate some noise bursts by flicking each section's mode button from S&H to lag and hold. I also added some variation to the patch by sending three CV variables from Pressure Points to the two Toppobrillo modules.

For more patch ideas, see the Sport Modulator page and manual here.

Schneiders London Testsalon Opening

Some pictures from the opening event at Rough Trade East last Sunday.









It's been a while since I've been down Brick Lane and I was amazed at the buzz on the streets. Rough Trade East is a great location for the Testsalon and I wish Andreas and the lads every success with the venture. Thanks to everyone who came along - it was great to meet you!



TOP: Cwejman RES-4, MMF-1, Toppobrillo TWF, A-132 VCA, Harvestman Hertz Donut, VCA-4MX; BOTTOM: A-147 VCLFO, A-160/1 clock divider/ sequencer, Fonitronik Attenuverting Mixer, Analogue Solutions SH-NZ, Make Noise Wogglebug & Maths, Bananalogue/ Serge VCS.

Above is a picture of the 6U case I took with me. I can happily confirm that it met Easyjet's carry-on luggage regulations. There was a sharp intake of breath from the passengers behind me as I opened the case at security in Berlin - the people at Luton didn't even bat an eyelid. I asked Easyjet about taking a 9U as carry-on: unfortunately, it's too big.

Putting together a 6U performance case was a real challenge. My normal approach is to ensure that I have all eventualities covered e.g. VCAs, polarizers, mixers etc., but this time the solution was to think in terms of the set I wanted to play and populate the case accordingly. Anything I hadn't used in rehearsal (mults, logic, sound-shaping filters, complex envelopes etc.) was easily left out.

My set comprised of three sections and relied on re-patching & repurposing the modules e.g. filter as oscillator, envelope as trigger delay etc. Rather than using LFOs, a joystick or keyboard/ Pressure Points, I made all changes manually.

Section one: white noise tuned by the RES-4 to provide a pad, the MMF-1 randomly pinged by the Wogglebug (the Allen Strange 'tail-chasing' patch); section two: my faux binary zone patch (MMF-1 through TWF as bassline), RES-4 pinged by clock divider for 'Berlin-style' stabs, high-pitched waveform discontinuity sound from Hertz Donut principal as high hat, modulator as kick drum and, section three, the RES-4 excited by the VCS and run through the TWF for some distorted klonks, with the HD providing some 'stupid' accompaniment and the MMF-1 rumbling the subs.

Part workshop, part gig, this was an interesting experience - despite rehearsing, the one thing I wasn't prepared for was shaky patch-hands. On more than one occasion, I missed the jack and hit the face-plate! Self-contained instruments like Maths, the Wogglebug & Hertz Donut are perfect for small systems (although the latter's secondary CV inputs, which need to be activated, are hardly performance-friendly!). The biggest lesson, though, was to bring your own monitoring: if you can't hear your music properly, you can't respond. Next time, I'll be wearing headphones!

Release: Best of Patch of the Day

I've just released The Best of Patch of the Day Vol. 1, which is available from my bandcamp page for three Euros.



The EP contains some patches from the past plus one new recording. Prebloom is a live performance featuring a Cwejman RES-4 & CTG-VC, Toppobrillo TWF, Doepfer A-143-1, Plan B Model 15 & Harvestman Hertz Donut VCOs, Makenoise Pressure Points and f(h) Choices joystick. I'll leave you to figure out the patch configuration from my previous examples!

PotD - Swings & Roundabouts

How to patch a thru-zero frequency shifter with two quadrature VCOs and ring modulators.



I love my Cwejman FSH-1 for its wide range and smooth analogue tone. The one thing it lacks is thru-zero capability. At slow settings, frequency shifters yield beautiful spatial effects. Thru-zero is the icing on the cake as it allows the up & downshift channels to 'swap sides'. Heard in stereo, this can sound great - or disconcerting, depending on the amount of shift!

So, how to go about patching one?

James Clark's Nord Modular tutorial on spectrum shifting explains the workings of a frequency shifter but stumped me on the need for all pass filters/ Hilbert Transformers. A post by Matt Jones at the Synthedit Yahoo Group offered the necessary clue:

"Out = (Input) * (Sine oscillator) + (Input shifted by 90 degrees) * (Cosine oscillator)
Changing the + sign to a - switches the amount of the shift from up to down …"

Here's the proof of concept:



In the recording you can hear me manually sweeping a DC voltage from positive to negative, biasing the modulator and causing the shifts to move from left to right.

My patch (see below) has three caveats: one, you need a Zeroscillator or similar to provide the thru-zero shifts (!). Two, unless you have the means of generating a cosine from your complex input signal, you're limited to simple sines. Three, it's fiddly and not 100% precise. That said, the results sound great:



The patch details: the ZO is used as the modulator. Set its bias to zero and patch the 0 & 90 degree outputs to the CV inputs of two ring modulators (e.g. A-133). I used the Doepfer A-143-9 QLFO as my signal as it provides the necessary outs. The 0 & 90 degree outputs were patched to the respective ring mods. The Toppobrillo TWF can be used to generate a cosine from another source, but I wanted to keep the patch as simple as possible.

To generate the upshift, I mixed the result of the 0 and 90 degree multiplications. To get the downshift, I subtracted the 90 from the 0 degree via an external inverter. The Cwejman VCA-4MX was used as the output to my final mixer. It's perfect for this task as it allows you to independently tap the mix of channels 1&2 and 3&4, which you can then pan left and right.

The fiddly bits: to bias the ZO correctly in both directions, I had to tune two voltages (+ve & -ve, Maths or Fonik's mh-01) and send them to the linear FM input via a sequential switch. It would have been easier to use the pulse output of the clocking LFO, but this didn't give me equal positive and negative bias i.e. the side-swapping effect was compromised. You can hear this in the first recording where I apply the bias manually. The second detail you have to watch is the mix/ subtraction balance to ensure clean up & down shifts, but this isn't too tricky. Just use your ears for both.

The ZO makes this patch possible. With zero bias, the oscillator comes to a stand-still. Any voltage you apply to the linear input will cause it to jump into action. Reverse the bias voltage and the ZO changes direction causing the shifts to swap sides. You could use a second A-143-9 as modulator, but would then lose this ability. Still, two QLFOs, an A-133 and mixer/ inverter offer an inexpensive single-sideband-modulation patch.

Buy Swings & Roundabouts.