Best Filter Modules for Intermediate 2026
So, you're past the basic oscillator and envelope setup and starting to crave some serious tonal sculpting? Filter modules are the key to unlocking that character, that grit, that warmth - or icy bite, depending on what you're after. But wading through the Eurorack jungle of filters can be overwhelming. This guide is for the intermediate player who wants to move beyond the basics and really start shaping their sound.
Last updated: April 11, 2026
⚡ The best filter modules in 2026 are Doepfer A-121d (top pick), Doepfer A-108 for tighter budgets, and Erica Synths Black LPG for pros — selected from 15 options across 7 brands, priced $119–$240, ranked by brand, price and popularity.
#1
⭐
3.0/5
AudioFu Score
Specs:
6/10
Detail:
5/10
Value:
8/10
Doepfer A-121d
by
Doepfer
Tonal Character
Classic Synthesis
Sound Shaping
Key Feature:
The A-121d is a workhorse filter module for Eurorack systems. Its dual filter design and delta control make it ideal for creating evolving textures and complex tones – a great choice for experimental sound designers and those seeking classic, resonant filter character. It's a fantastic value and a solid foundation for any modular setup.
PROS
- • Dual filters offer incredible flexibility for complex sound design.
- • Delta control provides unique and evolving timbral shifts.
- • Solid Doepfer build quality ensures long-term reliability.
- • Integrated mixer simplifies routing and signal management.
CONS
- • 8HP footprint can be limiting in smaller Eurorack cases.
- • Filter resonance can get quite aggressive, requiring careful control.
- • Limited filter modes compared to some more modern designs.
⭐
3.0/5
AudioFu Score
Specs:
6/10
Detail:
5/10
Value:
8/10
Art. 596074
$175
#2
⭐
3.0/5
AudioFu Score
Specs:
5/10
Detail:
10/10
Value:
8/10
Doepfer A-108
by
Doepfer
Sound Shaping
Audio Processing
Frequency Control
Key Feature:
The A-108 is a fantastic entry point into classic Moog-style filtering within a modular environment. It's a workhorse module, delivering that warm, creamy character ideal for pads, basses, and evolving textures – perfect for anyone looking to add a serious filter voice to their modular setup without a massive investment.
PROS
- • Classic Moog ladder filter topology delivers warm, resonant tones
- • Multiple slope options (6, 12, 24, 48dB) offer tonal flexibility
- • Robust build quality characteristic of Doepfer's meticulous engineering
- • Excellent value for a filter module of this quality and character
CONS
- • Limited output stages restrict routing options slightly
- • Transistor ladder filters can be sensitive to component aging
- • Requires Eurorack format modular system for integration
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3.0/5
AudioFu Score
Specs:
5/10
Detail:
10/10
Value:
8/10
Art. 170862
$169
#3
⭐
3.0/5
AudioFu Score
Specs:
6/10
Detail:
5/10
Value:
8/10
Erica Synths Black LPG
by
Erica Synths
Audio Processing
Subtractive Synthesis
Tonal Character
Key Feature:
The Black LPG is a clever little module that gives you a lot of bang for your buck. It’s perfect for sound designers and experimental musicians who want a versatile filter/VCA in a small space—the resonance overdrive is a real highlight and adds a lot of character. It’s a great starting point for modular exploration, too.
PROS
- • Unique filter/VCA hybrid design offers incredible sonic flexibility
- • Resonance overdrive adds a satisfying grit and character
- • Compact 10HP footprint maximizes space in modular setups
- • Excellent value proposition for the feature set offered
CONS
- • Limited modulation destinations compared to larger filter modules
- • Offset control can be a bit finicky to dial in precisely
- • May not offer the pristine clarity of dedicated, high-end filters
⭐
3.0/5
AudioFu Score
Specs:
6/10
Detail:
5/10
Value:
8/10
Art. 509918
$208
#4
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3.0/5
AudioFu Score
Specs:
6/10
Detail:
5/10
Value:
8/10
Doepfer A-121d VE
by
Doepfer
Tonal Character
Frequency Control
Classic Synthesis
Key Feature:
The A-121d VE is a solid, workhorse filter module that nails that classic Moog-esque vibe. It's a great entry point into more complex filtering, especially for those wanting that vintage warmth and character without a ton of bells and whistles. Perfect for sound designers and experimental musicians looking for a reliable, space-saving filter pair.
PROS
- • Excellent resonance character, classic Moog-inspired sound.
- • Dual filter design allows for complex, evolving textures.
- • Compact 8HP footprint maximizes modular space efficiency.
- • Well-built, sturdy construction characteristic of Doepfer quality.
CONS
- • Limited filter modes compared to more modern, complex filter designs.
- • Normalization can be confusing for beginners to modular synthesis.
- • Input level controls lack fine-grained adjustment for subtle shaping.
⭐
3.0/5
AudioFu Score
Specs:
6/10
Detail:
5/10
Value:
8/10
Art. 596076
$186
#5
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2.9/5
AudioFu Score
Specs:
6/10
Detail:
5/10
Value:
8/10
NANO Modules ST-FONT
by
NANO Modules
Sound Shaping
Frequency Control
Classic Synthesis
Key Feature:
The ST-FONT is a seriously cool little module for adding stereo movement and character to your patches. It's perfect for sound designers and experimental musicians who want a compact, versatile filter with a bit of edge. It’s a great starting point for exploring stereo filtering without a huge investment.
PROS
- • Stereo filtering dramatically widens soundscapes, adding real depth.
- • The 'Wild' resonance mode delivers satisfying, gritty textures.
- • CV offset control offers nuanced filter modulation possibilities.
- • Compact 14HP footprint maximizes space in tight Eurorack setups.
CONS
- • The drive control can easily overload, requiring careful gain staging.
- • Limited filter modes compared to some higher-end filter modules.
- • The attenuators feel a little plasticky, not the most premium feel.
⭐
2.9/5
AudioFu Score
Specs:
6/10
Detail:
5/10
Value:
8/10
Art. 604124
$215
#6
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3.1/5
AudioFu Score
Specs:
6/10
Detail:
6/10
Value:
9/10
ADDAC 607 Crossover
by
ADDAC
Subtractive Synthesis
Audio Processing
Frequency Control
Key Feature:
The ADDAC 607 Crossover is a surprisingly versatile little module for refining your sound. It's perfect for sound designers and experimental musicians wanting precise band separation and shaping without a huge commitment. The clean filter character and compact size make it a great addition to any Eurorack system.
PROS
- • Excellent Sallen-Key filter provides a clean, musical tone.
- • Flexible crossover frequencies allow for precise frequency shaping.
- • Compact 6HP footprint maximizes valuable rack space.
- • Individual band volume controls offer nuanced tonal sculpting.
CONS
- • 6HP is quite cramped; patching can be challenging in tight racks.
- • Limited crossover frequencies might restrict advanced processing needs.
- • Analog design means potential for drift, requiring occasional calibration.
⭐
3.1/5
AudioFu Score
Specs:
6/10
Detail:
6/10
Value:
9/10
Art. 618345
$120
#7
⭐
2.9/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Endorphin.es Squawk Dirty To Me Silver
by
Endorphin.es
Audio Processing
Classic Synthesis
Sound Shaping
Key Feature:
The Squawk Dirty To Me is a fantastic character module for Eurorack. It’s a surprisingly versatile stereo filter with a real edge – perfect for sound design, experimental music, or adding grit to more conventional patches. This is a great option for anyone wanting a unique sonic signature without needing to commit to a full modular system.
PROS
- • Exceptional filter character, uniquely aggressive and musical.
- • Integrated VCA streamlines patching and sound shaping.
- • Meta-CV scanning provides evolving, dynamic filter textures.
- • Compact 6U panel saves valuable rack space.
CONS
- • Limited filter type control compared to a full Grand Terminal.
- • 120mA draw can be significant for power-constrained racks.
- • Serial HP filter might be too aggressive for subtle filtering.
⭐
2.9/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Art. 536289
$197
#8
⭐
2.9/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
7/10
Befaco BF-22 Sallen Key Filter
by
Befaco
Subtractive Synthesis
Tonal Character
Audio Processing
Key Feature:
The BF-22 nails that classic MS-20 filter vibe without the full modular commitment. It's a great way to add some grit and character to your Eurorack, especially if you’re after that raw, aggressive sound, and it's an excellent entry point into more complex filter designs.
PROS
- • Authentic MS-20 filter character, surprisingly warm and musical
- • Versatile 12dB/6dB modes offer broad sonic shaping
- • Link switch creates complex, evolving filter textures
- • Solid build quality with robust pots and reliable switching
CONS
- • 17HP footprint can be limiting in smaller racks
- • Limited input gain range requires careful level matching
- • Resonance can get quite aggressive, demanding careful modulation
⭐
2.9/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
7/10
Art. 466964
$241
#9
⭐
2.8/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
9/10
Doepfer A-120 Vintage Edition
by
Doepfer
Classic Synthesis
Frequency Control
Tonal Character
Key Feature:
This A-120 VCF1 is a solid choice for anyone wanting that classic Moog-style filter in their modular setup. It’s a straightforward, workhorse filter that nails the vintage vibe, and it’s a great starting point for exploring filter modulation – ideal for experimental sound design or recreating classic synth tones.
PROS
- • Classic Moog filter emulation delivers a warm, resonant character.
- • Robust construction with discrete transistors for reliable performance.
- • Vintage edition offers a distinct sonic signature compared to later models.
- • Compact size integrates easily into dense modular systems.
CONS
- • Limited filter modes compared to more modern designs.
- • Vintage components may exhibit slight inconsistencies in performance.
- • The 'vintage' designation can imply slightly higher noise floor.
⭐
2.8/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
9/10
Art. 383620
$127
#10
⭐
2.8/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Tiptop Audio Forbidden Planet Analog Filter
by
Tiptop Audio
Sound Shaping
Frequency Control
Tonal Character
Key Feature:
The Forbidden Planet nails the Synthacon’s character, offering a raw, vintage filter sound perfect for experimental sound design and gritty basses. Its compact size makes it easy to integrate into smaller modular rigs, but be prepared to dive in and really explore its possibilities – it’s not a plug-and-play experience.
PROS
- • Authentic Steiner Parker Synthacon vibe delivers unique, resonant character
- • Excellent self-oscillation capabilities for aggressive sound design
- • Compact 8 TE module fits well in most Eurorack systems
- • Flexible multi-mode operation opens creative sonic possibilities
CONS
- • Limited filter modes compared to more complex filter modules
- • Power draw could be a factor in power-constrained systems
- • Steeper learning curve for mastering all operational nuances
⭐
2.8/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Art. 449219
$152
#11
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2.7/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Endorphin.es Squawk Dirty To Me
by
Endorphin.es
Classic Synthesis
Tonal Character
Subtractive Synthesis
Key Feature:
The Squawk Dirty To Me is a seriously fun and creative filter module. It’s perfect for experimental sound design and adding unique movement to your patches, especially if you’re already familiar with the Grand Terminal’s sonic character. It's a great way to add some unique character without a massive commitment.
PROS
- • Exceptional filter variety; Grand Terminal sounds in a compact module.
- • Integrated VCA cleans up signal routing considerably.
- • Meta-CV scanning introduces evolving, unpredictable textures.
- • Serial high-pass effectively cleans up muddy low-end frequencies.
CONS
- • 6HP is tight; space is at a premium in most racks.
- • Limited modulation destinations beyond cutoff and resonance.
- • Filter types, while diverse, might feel overwhelming for beginners.
⭐
2.7/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Art. 471567
$197
#12
⭐
2.6/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Erica Synths Black Polivoks VCF V2
by
Erica Synths
Frequency Control
Tonal Character
Audio Processing
Key Feature:
This Erica Synths Polivoks VCF V2 is a fantastic little module for recreating that gritty, Russian synth vibe. It’s a no-frills design, but it nails the aggressive character of the original Polivoks filter, perfect for industrial, experimental, or anyone craving a raw, analog edge in their modular patch. A great choice for those seeking a specific, iconic sound without a huge commitment.
PROS
- • Authentic Polivoks character with original K140UD12 chips
- • BP mode delivers aggressive, resonant sweeps and textures
- • Compact 10HP footprint ideal for space-constrained modular systems
- • Simple, direct controls allow for immediate sonic exploration
CONS
- • Limited filter modes compared to more versatile options
- • Can be quite aggressive and noisy at higher resonance settings
- • No attenuators on CV inputs; signal levels require careful management
⭐
2.6/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Art. 420027
$218
#13
⭐
2.6/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Erica Synths Black Multimode VCF
by
Erica Synths
Sound Shaping
Subtractive Synthesis
Classic Synthesis
Key Feature:
The Erica Synths Black is a fantastic, character-rich multimode filter that's a real workhorse. It's a great entry point into more complex filtering, especially if you’re chasing that vintage Moog vibe, and its small size is a huge bonus for Eurorack users. Perfect for sound design, experimental music, and adding warmth to synths.
PROS
- • Gorgeous, warm filter character with genuine germanium overdrive tone
- • Excellent resonance sweep provides screaming, musical feedback possibilities
- • Compact 10HP footprint makes it ideal for dense modular setups
- • Well-implemented attenuators offer precise CV control and shaping
CONS
- • The lowpass mode can be a bit muddy with extreme resonance
- • Limited filter modes compared to some pricier, more complex options
- • Depth (35mm) might be restrictive in shallow Eurorack cases
⭐
2.6/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Art. 506132
$197
#14
⭐
2.6/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
9/10
Doepfer A-124-2 SE
by
Doepfer
Tonal Character
Frequency Control
Audio Processing
Key Feature:
The A-124-2 SE is a fantastic, compact filter for adding some gritty character to your modular system. It's a great entry point into Doepfer’s filter design philosophy, perfect for those seeking a classic, aggressive sound without a huge footprint or premium price tag – especially useful for techno, industrial, and experimental sound design.
PROS
- • Excellent filter character – wasp-like aggression and warmth.
- • Slim 4HP footprint maximizes space in tight Eurorack cases.
- • Robust construction with Doepfer's signature quality components.
- • Versatile multimode options offer a wide range of tonal possibilities.
CONS
- • Limited resonance control compared to some higher-end filter modules.
- • Attenuation on one CV input can feel restrictive for complex modulation.
- • The SE designation doesn’t represent a massive sonic leap over the original A-124.
⭐
2.6/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
9/10
Art. 595775
$131
#15
⭐
2.5/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Erica Synths Black 3109 VCF/VCA
by
Erica Synths
Classic Synthesis
Frequency Control
Sound Shaping
Key Feature:
The Black 3109 is a seriously punchy filter – it nails that classic Moog vibe. It’s a great entry point to Erica Synths' Black series and a fantastic choice for anyone wanting that aggressive, resonant low-pass sound without needing a massive patch bay. Ideal for techno, industrial, or anyone wanting a raw, gritty edge.
PROS
- • Aggressive, Moog-inspired filter character delivers classic analog warmth.
- • Level compensation avoids volume drops at high resonance, a genuinely useful feature.
- • Built-in VCA simplifies patching and offers a convenient all-in-one solution.
- • Compact 10U width optimizes space in dense modular setups.
CONS
- • Limited filter modes compared to more complex, higher-priced offerings.
- • The attenuators could benefit from finer resolution for precise CV control.
- • While versatile, its single filter type restricts broader sonic exploration.
⭐
2.5/5
AudioFu Score
Specs:
6/10
Detail:
4/10
Value:
8/10
Art. 543643
$204
How to Choose the Best Filter Modules
1
Filter Type
Moog-style ladder filters are your bread and butter for that fat, warm, resonant low-pass sound. State Variable filters offer more flexibility with simultaneous high and low pass outputs. Knowing what you want-a creamy pad, a searing lead, or something in between-will guide your choice.
2
Resonance Control
This isn't just about screaming feedback; it's about adding character and movement. A good resonance control offers a wide range, from subtle thickening to self-oscillation, and should respond predictably to modulation.
3
Modulation Capabilities
Can you modulate the cutoff frequency with envelopes, LFOs, or even velocity? This is what breathes life into your filters, allowing for dynamic movement and expressive textures. Look for CV input jacks and ideally, attenuators to dial in the modulation depth.
4
Steepness/Slope
The slope determines how quickly the filter attenuates frequencies. A steeper slope (24dB/octave) is more aggressive and useful for dramatic filter sweeps, while a gentler slope (12dB/octave) is smoother and more subtle.
5
Drive/Overdrive
Many filters offer a drive stage that adds harmonic distortion. This can be used to add warmth, grit, or outright fuzz, but be mindful of how it affects headroom and overall mix clarity. It's easy to get carried away and muddy the sound.
Buying Guide
At this level, you're probably willing to spend a little more for quality. Avoid the absolute bottom-tier clones - they often cut corners on component quality, leading to noisy operation and unpredictable behavior. Focus on modules with solid build quality, a responsive control panel, and a clear, defined sound. Don't chase the 'latest and greatest' - classic designs often have a reason for their popularity.
How This List Is Built
We don't play these instruments — we're a catalog, not a review desk, and we'd rather say so than pretend otherwise. This page ranks 15 filter modules from the Thomann catalogue, which is the largest single source of specification data in this category.
Position is computed, not curated. Four signals, in order of weight: how completely the manufacturer documents the instrument (number of published specifications), where it sits in the price range, how specific the model designation is — which filters out generic accessories — and whether a product image exists. The same inputs always produce the same order, so nothing here is shuffled to look fresh.
What this list is good for: narrowing a category down to a shortlist by spec and budget. What it isn't: a substitute for hearing an instrument. Before you buy, read hands-on reviews and, where you can, play it. Full methodology.
Frequently Asked Questions
Moog-style filters are known for their creamy, resonant low-pass character - think classic synth basslines. State Variable filters offer more flexibility, with simultaneous high and low pass outputs, making them great for complex filtering and stereo effects.
Mutable Instruments Shifting Pattern Generator is a surprisingly versatile option, offering multiple filter types and modulation capabilities for a reasonable price. Just be aware it's a bit more complex to learn initially.
Noise can be caused by a number of factors - cheap components, improper grounding, or excessive resonance. Try adjusting the resonance, reducing the drive, and ensuring your power supply is clean and stable.
It's not just about the filter type; it's about the entire signal chain. Experiment with overdrive, EQ, and subtle modulation to recreate the vibe of classic synths. Also, old filters often had limitations in headroom - pushing them closer to clipping can help emulate that characteristic sound.
Absolutely! Many filter modules can be used as external effects processors by sending audio from other sources through them. Just be mindful of input levels to avoid distortion or clipping.
