I’m a fan of full voice Eurorack modules and have a few in my rig. While they can be pretty utilitarian, and not as flashy or exciting as having different modules from different manufacturers to play with, I like the fact that they’re self contained, and that whoever made it, did so with a vision of what they wanted it to be as a whole, not just part of an unknown mixture of modules. Looking at the features that the Manther Growl boasts on its faceplate–which is quite a lot in a relatively compact space–I couldn’t wait to get it powered up to see what makes this module, um. . . growl.

A pared down version of the Manther desktop synth, the Growl uses the much revered CEM3340, an IC that was brought out of retirement in 2016 by the original manufacturer, Curtis Electromusic. This is the same chip that gave voice to vintage synths such as the Sequential Pro-1, OB-Xa, and the MemoryMoog, among others. Growl puts the CEM3340 to good use, having simultaneous Square, Triangle, and Saw waveform outputs, each with their own level controls, and CV in. You can get pretty crazy using LFOs and envelopes to modulate each waveform, and there’s also a Waveshape control with its own level control, as well as CV in for that, with a switch to select either Triangle wave only, or all waves to be affected by the Wavefolder. All of the wavefolding happens after the signal passes through the filter, and speaking of the filter. . . according to the Manther manual [manthual?] the filter is “based on” an SSM2044 chip, and sounds great. Frequency cutoff has CV in as does Resonance control. There is an ADSR for the VCA [with an invert switch] and the VCF, and both ADSRs have their own Gate inputs, and the ability to control the amount of the envelope in the outputted signal via their respected LED Level sliders. I like being able to mix the envelopes into the overall sound, something that is common enough, but still not found on every envelope generator. With the Level all the way up, the ADSR is bypassed on both, and each ADSR also has its own output to hook up with other modules.

An onboard LFO [choose from Sine, Square, Ramp, Saw, or Random] further increases the amount of modulation the Growl can do without ever leaving its own neighborhood, and is normalled to and has Level controls to modulate Pitch, Pulse Width, and Filter cutoff. There’s also an LFO output for syncing up to external sources. Bringing external audio into the Growl to process through the Growl’s filter is done via the Ext in, and along with selectable octave range, a fine control and a 1v/oct input rounds out all of the functions this module advertises on its front plate.

As you can see, the Growl’s got a lot to offer, and everything that’s on there makes sense; there’s nothing wasted and nothing superfluous, which is important because with all of these features, the Growl’s controls could have become really crowded, really fast. For the most part the layout is perfect: There’s plenty of room for fingers and cables; the knobs aren’t flashy but have a good feel; and the LED enhanced sliders at the bottom help break up what would otherwise be a monotonous onslaught of said knobs. I’m a fan of using sliders for ADSRs anyway, so it was and is a welcome sight. I’m not such a fan of having jacks in the middle of a module, something that the Manther Growl has, and I’ve heard people complain about this fact on other modules, which makes sense until you realize that in a 6/9/12U [and more] system—basically any system that has more than one row in it—every module has cables in front of it from other modules, not to mention modules that have jacks lined up vertically, etc., so it turns out to be neither here nor there. Still, I probably would have opted to put the jacks at the bottom, below the sliders, but either way, it wasn’t an issue and didn’t hinder my playing or enjoyment of the Growl in any way.

As for how it is in play, I liked the Growl. A lot. The combination of the CEM3340 and the filter was pretty easy to get, umm. . . growly and aggressive, and adding the waveshaper into the mix, the sonic possibilities are awesome and endless. There are so many options to tweak, change, modulate, etc., that I exhausted almost all of the outputs from my XAOC Devices Batumi patching into it while using the Growl’s internal LFO on random patched into the 1v/Oct to give it some pitch movement. The 1 V/oct tracked well, and Growl does excellent formant acid-y leads with a tiny bit of modulation on the VCF cutoff. Patching out of the VCF’s ADSR and into the Waveshaper was cool and yielded a lot, from 70s Heavy Metal backwards LP satanic messages to LPG type stuff, depending on the ADSR’s settings. Patching the Growl through with Sonocurrent’s M T2D that I was testing at the same time [see the review in this issue], I had a really killer squashed techno lead like a coked-up roller derby Wolfman Jack pitched high through a vocoder. While turning every knob and looking in every crevice, I noticed that when nothing external was patched in, and the EXT input knob was turned all the way, it would introduce harmonics into the voice. It added a little something extra and was kind of a fun trick to add a little extra meat to the sound. I usually kept that cranked.

The sounds of Growl really got me; however, there are a couple of things that I wish the Growl had: the first being that the LED enhanced sliders would change intensity in relation to voltage, as that would have been nice to have a visual indicator of the outgoing envelope cycle/s. Also, an LFO speed input [and visual indicator as well] would be nice so that you could use an external clock to control the Growl’s LFO speed. This is something that constricted my patching as I had to use the Growl as a master clock if I wanted to have the LFO synced with other modules.

Either way, I’ve thoroughly enjoyed my time with Growl, and this module is a powerhouse. I really liked its sound, and with the onboard waveshaper, and the two ADSRs. . . Again, there are so many options for control/modulation, you can patch it into itself in a ton of ways. Really flexible, really great sounding, and really intuitive? Sounds good to me.

26HP 300mA +12V 200mA -12V

Price: $499

malekkoheavyindustry.com