Bubblesound uLFO - Looking for similar DIY solution

Hello out fellow MI fans!

Yesterday, I took my Anushri and went to play with the two modular guys in town. It was very inspiring.
One person had a big Doepfer setup and the other had a smaller setup with hand picked modules of different brands.
One module in particular got my attention:

The Bubblesound uLFO.

That thing is amazing. It’s range for one LFO cycle goes from approx an hour and up way into the audible range, at 3,6kHz, making it a quite usable oscillator. All in all, this thing is a quite versatile module with many parameters and CV possibilities.

See it here: http://www.bubblesound-instruments.com/ulfo.html
And in action: http://www.youtube.com/watch?v=Zr2iVvYz6YE&feature=channel

The owner had two of them and especially when getting them to modulate each other, they produced some very impressive sounds that the big Doepfer rig with all its different modules couldn’t mimic.
I liked the sound of the uLFO as an oscillator much better than the Doepfer A110 even though being a VCO is not it’s main goal.

I crave that Bubblesound uLFO as a play pal for Anushri… but being a student, price is an issue, so I am looking for a way to build something similar instead.

I am no engineer and cannot design one myself. But maybe some of you know of advanced DIY projects for something similar?

Thanks for taking your time!


Looks like the cheapest way to get one of these is just buy one…

DIY versions of commercial products often end up much more expensive than the commercial version, (living in Denmark particularly, since ordering parts from fx the US is not really an option, unless you like paying a lot extra for tax & fee’s), although some eurocrack stuff could be built cheaper DIY, most of the DIY eurocrack community doesn’t do it, and frowns upon those that do(stealing each others modules and stuff is a big no-no)…

Still would be a cool option (student myself) :confused:

Direct link to the uLFO

249€ is an awful load for an LFO…

Whats the most interesting part about it? The different Waveforms?

it definitively looks like it’s a “standard” VCO with all kind of options, actually.

Well, yeah, it’s expensive for an LFO. But as MicMicMan comments, it’s got all kinds of options and works as a VCO as well.
And the sound of it as a VCO is really good!
Taste is a matter of… well, taste… but to my ears, when comparing either of the waveforms the uLFO could conjure up, to the same waveforms coming from the Doepfer, the uLFO just sounded much, much better.
But yes, fcd72 and V`cent, you are probably right. Buying the thing might be the best way to go.

As far as i can tell the DOEPFER Stuff sounds a bit boring just because it outputs very Clean Signals, at least thats what my DIY Synth does…

Yes, that might be it. Clean is no fun! :wink:

oh, doepfer can do dirty alright.

re bubblesound , they deliberately use OOP components from way back. It is an LFO that can behave like a VCO with waveshaping. I have one.
Not sure there is anything else quite like it. I certainly have not got the retro-engineering-fu to conjure up a copy.

there are some interesting diy solutions out there for lfos too. muff wiggler has an option atm, Taylor Livingston is in the process of making an 8x LFO and an 8x VCA for drone sounds with cycles of several minutes and into audio range. the over one hour cycle is ultra massive of course and i don’t know of something else that does this.
some other good stuff can be found at ken Stone’s site CGS
(psycho LFO for example)
and MFOS of course. also check out Thomas Henry’s Cucamonga VCLFO at Magic Smoke
LFO’s aren’t the most expensive modules and comparably easy to build.
you could always breadboard / stripboard a design and experiment with some really big cap values for longer duration times.

I’d start there . Indeed i did start there…

mic.w, sure, Doepfer too knows some tricks :slight_smile: I just really like how that uLFO sounds. It’s got something unusual about it.

Fitvideo, yes, I suspect it must be those OOP components that make a big part of the difference. Thank you for confirming that I’m not just imagining things… this module rocks :slight_smile:

rosch and fcd72, Thanks! Now I have plenty of new sites to learn from :slight_smile:

got my uLFO with a little discount a while back from Escape From Noise, I really like it too, it tracks octaves well when used as a VCO and sounds very good…

Sounds good!
Any tips when it comes to choosing a power supply? I guess too cheap is a bad idea when steady voltage is king, right? What did you guys get for your modulars and why did you decide on that one?

depends how big you want to go, doepfer and a few others make distro boards and psus , as a good start you can look at tip top uZeus (microZeus), you will at some point probably need 5v so that is worth checking a well. I like the uZeus stuff. I have one or two modules that need their own power, as they have valves in.

I use a simple 35€ Switching Power Supply and Rails i soldered myself on a simple PerfBoard. Works perfect for what i have right now (Anushri, Little Dieter + a bunch of ProtoTypes…)

Rolled my own, off a toroidal transformer and an old-school dual LM317/337 combo for /-15V and/-5V. It has some extra trickery from the classic Art of E book for lower ripple. The digital bits in the MIDIbox Seq v4 is fed from a simpler PSU running off an E-core transformer. All modules have ferrites near their power connectors.

This is very inefficient, but I was afraid of noise by-products from switching PSUs back then. This has no such issues, the entire thing sounds very clean and is noise-free unless I dial some in, or mangle the sound with the Germanizer distortion…

It sounds like it’s up to me to figure out my own needs before I decide. Thanks for sharing your info with me!

uLFO is a full-fledged VCO, just with lower frequency ranges of operation-only difference between that and the more orthodox VCOb in the oscillator core is that the VCOb has an expensive Analog Devices expo pair and a styro cap whereas the uLFO has the old japanese 2SA798 transistor pair and a mylar cap. My VCOb and uLFO track each other in audio range really well. A big part of the sound would be the triangle core design and the abundance of waveshaping options. They are extremely well-made and I agree it’s worth the price-would never get rid of mine.

f you want DIY VCOs/LFOs look at the various Thomas Henry 555 designs that Matthias (fonitronik) Hermann is currently offering on Muffwiggler-funky, unique and somewhat unusually for DIY they have options for board mounted jacks and pots (avoiding point-to-point wiring), and he also offers nice panels. Perfect for someone who’s cut their teeth on MI kits…