Make Noise QPAS: Quad Peak Animation System


I’ve owned Three Sisters, Belgrad, and Twin Peak. Comparing features and my impressions of them:

Three Sisters: Three filters with separate or mixed inputs and outputs. Can switch between triple bandpass and a lowpass/variable bandpass/highpass config. Controls are Freq and Span (adjusts the low and high bands’ distance from the center). Has negative Q, which is pretty interesting. The resonant sound of the filter can never really be dialed out. Nice for self-oscillation.

Belgrad: Two peaks, with switchable states and a single input and output. Frequency, span, and level balance control. Switchable cross-modulation between peaks. It’s flexible, has lots of variety in how it sounds with self-oscillation, but to me it felt harder to use than Three Sisters (maybe due to feeling like there were too many options selected in a discontinuous way) and the general sound for subtractive use isn’t as nice as Sisters.

Epoch Twinpeak: Morphs from a single peak lowpass to dual peak variable width bandpass (with a high Q it might as well be two bandpasses) – so it’s missing highpass unless you patch that externally via inverting and mixing with the dry signal. Two inputs (crossfaded manually), one output. There are knobs to set the two peaks separately, and each can be modulated separately, but there’s a single V/OCT input that applies to both. (Functionally, I prefer that setup because you can FM one peak while keeping the other clean and still tracking pitch.) Does not do sustained self-oscillation but pings amazingly well, and the crossfade input lets you hybridize between pinging and “traditional” use. I honestly don’t like the character of its resonance as a “normal” filter for a lot of purposes, but I do like it applied to a dubby delay.

QPAS: Obviously I don’t own it, yet :slight_smile: Like Twinpeak the resonance never goes into sustained self-oscillation, but I like its sound character a lot better than Twinpeak. Ringing out after the input has decayed sounds gorgeous IMHO, as does the “smile pass” as a phaser. It seems a bit unfortunate that it lacks a CVable frequency offset between channels, which would be helpful for serial or independent mono, or the FM-vs-no-FM trick I like with Twinpeak.


Very curious to compare this to the SSF Stereo Dipole when it comes out too, seems like they have different enough functionality to justify some serious digging. Both sound absolutely amazing in demos so far. Andrew posted this yesterday, thought it was pretty funny:

I think he’s also working on a super extensive stereo VCA module coming soon. We are all very spoiled with these incredible options, seems like 2019 will be a great year for new choices in eurorack.


for your consideration: another “multi-dimensional signal processor with stereo inputs and outputs” announced today


QMMF-4: Four discreet multimode filters that can either self-oscillate (conventional) or not (similar circuitry to RES-4); each provides its own V/OCT input and attenuverted FM input; each has it’s own VCA (post-filter), and indeed, each has its own input. Input and output buses are provided if you want to treat the entire unit as a filterbank. Not stereo, but you can patch it in a stereo manner. No macro controls (along the lines of SPAN or RADIATE) other than a master FM that affects all four filters equally. (It’s otherwise up to you to patch up whatever animation you want to each filter separately.) I would describe the QMMF-4 as a comparatively generalized studio tool. The QMMF-4 is not notably playable. It is notably good at pinging in RES mode (it is an elaborated RES-4) and independent pitching of each filter is a plus there. It’s decent at formants if you’ve got the time and persistence to set them up. It is capable of adding nice saturation, and it can certainly can do swishy/phasery-sounding stuff with moving peaks and notches.
Top-of-the-line components and stability/predictability with (staggering) price and size to match. Cwejman character (whatever that means, but it’s a thing… maybe a bit clinical).


Not to hijack the MakeNoise thread, but the best thing about all these stereo modules in my opinion is that its now way easier to route feedback around my rack :slight_smile:


I’m definitely more drawn to the SSF in this category. Seems like it has a broader range of musical uses. No way to know til I play either of them though.
And when it comes to buying more modules (when I’m really pretty well set) it always comes back to the question of what additional Mannequins unit(s) I could buy with the same money ;-). 3S included in this case.


After thinking about this alot, I think the comparison to Three Sisters is misplaced. The difference between 1-to-4-in 1-to-4-out and 1-in 4-out x2 is pretty massive.

I’m drawn to the QPAS and the Sisters mostly because I have only two hands. Sure CV control; but for my use, having thoughtful master controls that manipulate sound in complex ways is very desirable.

Prism seems to meet that need too in a different way I think, but I would need to hear more.


The Perfect Circuit presentation made me really happy… If anyone hasn’t watched it I urge you to.


I’m in …can’t wait


Anyone know why there’s two frequency CV controls? I can’t figure it out. Do the two filters have their own frequency? (One knob but two CV controls is confusing me).

The manual isn’t posted yet, and I don’t see anything in the 7 minute demo video that explains it. I haven’t watched the live stream…is this obvious and I’m just not seeing it?


One is probably calibrated for 1v/o while the other has an attenuverter for general frequency modulation.


what I (completely idly) wondered was if the attenuated frequency input was linear or exponential.


My assumption is that the main knob is a frequency offset applied to both filters, while there are CV inputs for each of the two filters, with the CV for the first normalled to the second if you want to CV them together.


My Sisters has almost always been patched in stereo in the past few months… I think this will be replacing it. Smile Pass in stereo is just magically liquid.


ahhh, the big winner of this video for me is actually the audio-rate modulation into the “chk-chk” input that sounds like a weird combo between AM and sample-rate reduction!

…I guess this probably joins Akemie’s Taiko, Rings and, you know, actual general-purpose VCAs in my hypothetical, never-to-be-realized second row :joy:


Yeah, that was another thing Walker Farrell explained in the chat – one unattenuated, one attenuated. Both of them apply equally to left and right sides.


How much does this thing cost, like $500 ?

if anything, it only makes me realize i can (should) be patching with my existing filter(s) more creatively


$379 of 20 characters.


As others have said, it’s most likely one with an attenuverter, one without (to make it easier to track 1V/oct).

IMO, filters should always have at least 2 CV inputs, and really 2 audio inputs too. In a typical “East-coast” style patch, you’re going to want to track the keyboard and add modulation to the filter frequency cutoff. Also, it makes feedback patching much more straightforward.

It’s even better if they have attenuverters on the CV input (and audio input, but that’s more unusual). Inverted audio out back into a frequency CV input is a particularly fun patch…


I was also in the stream chat, and re:1v/o, I recall not seeing a concrete response. Maybe I’m missing a step on this inquiry, but it’s apparently impossible to get it to self-oscilate even with feedback patching - which is something Walker did say. I recall the stream showing pitching the resonance around a bit, but I dunno if we should expect perfect pitch tracking? :thinking: I’m certainly looking forward to the manual!