Stupidly useful, simple & small // Low Fat VCF from AJH Synth

video upload by DivKid

"Here's a fun one and something stupidly simple, really easy to use, small, affordable but way more useful than you might think. It's the Low Fat VCF from AJH Synth, which is a 2HP non resonant (it's supppppeeeer smooth) high pass filter.

I think my favourite thing is using it to pair with low pass filters and to make a variable width band pass filter. It's also nice as a simple "clean up the mix" tool, as a pseudo spectral sidechain, multiband ducking style device or just for performance sweeping low end out of things."

"The Low Fat filter packs a switchable 6dB and 12dB slope High Pass Voltage controlled Filter into a miniscule 2HP of rack space, with a very low power consumption of less than 12mA per rail.

Sometimes there is just too much bottom end in a patch and it swamps everything else, by feeding it through the Low Fat Filter we can remove some of this bottom end to balance things up.

It also makes a great companion to the MiniMod Transistor Ladder Filter and can be placed before or after this in a patch to create a Band Pass filter with a variable passband and a choice of a softly rolling 6dB slope or a stronger 12 dB slope.

It's a great way to populate one of those frustrating gaps in your eurorack modular case with something that is deceptively usefuI.

In Depth

The LOW FAT is a new 2hp Eurorack module by AJH Synth, it's a High Pass filter, with frequency control by either manual pot, and/or external CV with attenuator. It's intended to compliment other filters, particularly low pass VCF modules, in practical tasks such as removing excessive low frequencies, for example when the bass is swamping a mix. It can be switched between 6dB (1 pole) response and 12dB (2 pole) response.

By patching a CV signal to the FCV input it can be voltage-controlled and used musically as with any other VCF. When used in conjunction with a LP filter it forms a fully customisable band pass filter, allowing the range of passbands to be cherry-picked. Feeding in a 1V/Oct pitch CV and setting the FCV pot to a suitable level allows it to track an incoming pitch CV, so the amount of High Pass filtering remains constant as the pitch of the incoming VCOs traverse up and down the frequency range. This can be particularly useful in creating percussive sounds, such as snares and hats, but also on sequenced bass lines. Since it is only 2HP it's a great way to occupy one of those frustrating gaps in your eurorack modular case with something that is deceptively useful, and adds another dimension to the classic bass monster that is the Transistor Ladder Filter."