Plugin Boutique has Soundtoys FilterFreak on sale for $39, which is 73% off the regular price of $149. The deal runs until April 28th.

FilterFreak is still one of my favorite filter plugins for sound design. There are plenty of newer filter modulation plugins around, but I keep coming back to this one.

I love the sound, and although the modulation is fairly limited, it feels good, and the plugin is simple to use overall. It’s perfect for quickly getting some nice-sounding filter modulation.

I lean on FilterFreak a lot on synths to add movement to pads, and on textured or ambient sounds to make them more interesting. With a bit of modulation, you can turn a static drone into something much more interesting, whether you need something percussive or a short musical sequence.

FilterFreak recreates the sound of classic resonant analog filters. You get highpass, lowpass, bandpass, and band-reject modes with 2 to 8 poles, plus seven analog saturation styles that range from warm distortion to pumping compression.

The filter sounds fantastic. If you push the resonance hard enough, the filter self-oscillates. And if you drive it harder, it breaks up in a lovely, super crunchy way, just like hardware.

Rhythm Mode adds tempo-synced motion, with pre-made patterns, a Rhythm Editor for designing your own, and a Groove knob for swing or shuffle. Envelope and ADSR modes let the filter follow incoming audio for auto-wah and similar effects.

The bundle includes both FilterFreak 1 (a single filter) and FilterFreak 2 (two filters running in series or parallel).

Overall, I think this one is almost a must at this price if you’re looking for an analog-style modulated filter for sound design and jamming with your favorite synths.

By the way, I found two more awesome deals on Plugin Boutique.

73% OFF Soundtoys SuperPlate

SuperPlate is also 73% off, down to $39 from $149 (until April 28th). It models five classic plate reverbs (EMT 140, EMT 240, Audicon, Stocktronics RX4000, and EcoPlate III) and offers three preamp options (Tube, Solid-State, and Clean).

What’s pretty cool is that you also get infinite decay, built-in pre-delay, modulation controls, a 4-band EQ, and a decay ducking feature that shortens the tail when the input is loud.

Oh, and another nice touch is that the Soundtoys’ Little Plate is included with the purchase.

78% OFF Softube Transient Shaper

Softube Transient Shaper is down to $19 from $89 (78% off until April 30th). It’s a dual-band transient processor that lets you sharpen or soften attack and sustain across the full spectrum or only the high or low frequencies.

The crossover is user-selectable, and there’s a Clip section for output distortion. I love using this one on drums, but it’s also handy on vocals, piano, bass, and guitar.

All three plugins are available in AU, VST, VST3, and AAX formats for macOS and Windows, and they require a free iLok account (no physical USB iLok needed).

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Get the deals:

Deal of the day 🔥: Get the Softube Transient Shaper for only $19 (80% OFF)!

Last Updated on April 21, 2026 by Tomislav Zlatic.