GRN vs Output Portal: Which Granular Plugin Should You Buy? (2026)

Quick Answer (TL;DR)

Price Comparison: GRN vs Portal

Let's start with the most obvious difference. GRN costs $29.99 as a one-time purchase. Output Portal costs $149 at its regular price, though it occasionally goes on sale for around $75 during promotions. Portal is also available through Output's subscription service, Output One, at $14.99/month.

At full price, Portal costs roughly 5x more than GRN. Even at its best sale price, it's still more than double. For producers on a budget — or anyone who doesn't want to spend over $100 on a single effect plugin — GRN is the clear Output Portal alternative at a fraction of the cost.

Both plugins are one-time purchases with lifetime updates for their respective major versions. GRN is currently at v1.9.5 and includes lifetime free updates. GRN also offers a 14-day money-back guarantee if it doesn't work for you.

Core Granular Engine

Both GRN and Portal are real-time granular FX plugins. They capture incoming audio into a buffer, slice it into tiny grains, and let you manipulate those grains to create new textures. Both can produce shimmering pads, glitchy stutters, pitched textures, and ambient soundscapes.

GRN uses a 2.73-second circular buffer with up to 16 simultaneous grain voices. Its grain engine includes controls for grain size (10–500ms), density (up to 50 grains per second with tempo sync), stereo spread, spray (position scatter), pitch shift (±2 octaves), and dry/wet mix. All six core controls are visible on the main interface at once.

Portal's grain engine offers similar core functionality — density, size, pitch, stretch, delay, and pan — but adds a randomness parameter for several controls (indicated by a diamond icon beneath each dial). Portal's grain sizes range from 0.50ms to one second, and density can sync to tempo from 64th note triplets to one bar. Portal also includes a time stretch feature and a "humanize" control that adds natural envelope variation.

Both engines produce high-quality granular output with minimal artifacts. The core granular sound is comparable between the two — the differences come down to the additional features wrapped around that engine.

Features Only GRN Has

GRN includes several features that Portal does not offer. These aren't minor extras — for many producers, they're the reason GRN fits their workflow better.

• Randomizer: One-click randomization with musical profiles (Ambient, Shimmer, Glitch, Subtle, Deep). 70% of randomizations use musical profiles, 30% are wild cards. Portal has no randomizer.
• Scale Quantization: Three pitch modes — Free, Chromatic, and Scale. In Scale mode, pitch is quantized to Major, Minor, Major Pentatonic, or Minor Pentatonic scales with a selectable root note. This keeps granular output musical without manual pitch management. Portal offers scale-based pitch modulation but lacks GRN's dedicated per-grain quantization with jitter snapping.
• Harmony Mode: Adds per-grain pitch intervals — Octave Up, Octave Down, Fifth, or Random. This creates instant harmonic richness from a single audio source. Portal doesn't have an equivalent feature.
• Feedback Engine: A full feedback loop with delay (10–2000ms), three saturation modes (Warm, Tube, Crunch), stereo width via Haas effect, wobble (tape-style pitch drift), plus highpass and lowpass filters. This is a complete delay/saturation section, not just a simple feedback amount.
• Freeze Mode: Locks the circular buffer so grains keep replaying the same captured material. Creates evolving, infinite textures from a single moment of audio.
• CLAP Support: GRN supports VST3, AU, and CLAP on Windows, macOS, and Linux. Portal supports VST, VST3, AU, and AAX on Windows and macOS only — no Linux, no CLAP.

Features Only Portal Has

Portal is a more feature-rich plugin overall. It has more parameters, more presets, and more modulation options. Here's what Portal offers that GRN doesn't.

• 250+ Factory Presets: Portal ships with over 250 professionally designed presets. GRN includes 10 factory presets plus a user save/load system. If you rely heavily on browsing presets for inspiration, Portal has a significant edge here.
• XY Macro Pad: Portal's main interface features an animated XY pad that controls two macro parameters. You can drag and drop to assign any parameter to the X or Y axis, creating complex real-time performance controls.
• Modulation Envelopes: Two modulation envelopes that can be connected to any parameter. Envelope shapes can be simple, complex, randomly generated, or user-drawn. This gives Portal deep sound design capability that GRN doesn't match.
• 7 Built-in Effects: Portal includes 7 FX processors plus a master compressor and filter. GRN's effects are limited to its feedback engine (delay + saturation + filters).
• Grain Delay: A dedicated delay section that feeds output back into the grain engine based on a feedback amount. This is different from GRN's feedback engine — it's specifically integrated with the granular processing.
• Time Stretch: Slow down and stretch sounds with optional tempo sync. GRN doesn't have a dedicated time stretch control.
• AAX Support: Portal supports AAX for Pro Tools users. GRN does not support AAX.

Sound Quality: GRN vs Output Portal

Both GRN and Portal produce high-quality granular output. The core granular engines in both plugins use overlapping grains with smooth windowing to minimize artifacts, and both handle pitch shifting cleanly across a wide range.

GRN uses Catmull-Rom cubic interpolation for grain playback, which provides smooth pitch shifting without noticeable aliasing. It processes internally at 32-bit float and supports sample rates from 44.1kHz to 192kHz. The automatic gain compensation system uses a peak-weighted RMS measurement to keep output levels consistent as you adjust parameters, with a soft clipper to prevent harsh digital clipping.

Portal also delivers clean granular processing. Its "humanize" feature adds subtle envelope variations that can make the output feel more organic and less repetitive — something GRN doesn't specifically offer (though GRN's spray and jitter parameters serve a similar purpose).

In my experience, the raw granular sound of both plugins is very close. The difference is more about workflow and what happens around the granular engine. Portal's built-in FX chain means you can shape the sound further without leaving the plugin. GRN's feedback engine adds a different dimension — the delay-into-saturation loop creates textures that Portal doesn't replicate as easily.

Neither plugin is going to sound noticeably "better" to your listeners. The quality gap, if any, is in the tools around the engine, not the engine itself.

User Interface and Workflow

This is where GRN and Portal diverge most sharply. GRN was designed for speed and simplicity. All six core controls (Size, Density, Spread, Spray, Pitch, Mix) are visible on the main screen. Pitch mode selection, filters, jitter, and output controls sit alongside them. The feedback section expands below the main controls when activated. The total parameter count is 27.

GRN's interface is resizable from 75% to 200% and includes a real-time waveform visualizer showing the buffer contents and grain positions, plus a grain timeline visualizer. The randomizer and preset browser are in the header bar. You can go from opening the plugin to hearing interesting granular textures in seconds.

Portal's interface is more complex. The main page features the XY macro pad, grain controls, and a modulation section. An advanced mode reveals the full parameter set. There's a value readout panel, built-in tooltips, and a favorites system for presets. The FX chain adds another layer of controls.

If you want to get results fast with minimal friction, GRN's six-knob layout is hard to beat. If you want deep parameter access and complex modulation routing, Portal's interface supports that level of detail. It comes down to whether you value speed or depth in your workflow.

CPU Performance

GRN is lightweight by design. It uses a maximum of 16 grain voices with efficient Catmull-Rom interpolation and has zero samples of latency. The plugin is built in JUCE with careful CPU optimization including fixed-size grain pools and minimal memory allocation during processing.

Portal is generally reported to use more CPU, particularly when multiple FX are active and grain density is high. This is expected given that it has more processing stages (7 FX + compressor + filter + modulation). Some users have noted CPU spikes with complex patches.

For most modern studio computers, neither plugin will cause issues. But if you're running a large session with many instances, GRN's lower CPU footprint gives you more headroom.

Platform and DAW Compatibility

GRN supports VST3, AU, and CLAP formats on Windows 10+, macOS 10.13+ (Intel and Apple Silicon native), and Linux (Ubuntu 22.04+, Debian 12+). It works with all major DAWs including Ableton Live, FL Studio, Logic Pro, Cubase, Studio One, Reaper, and Bitwig. Each purchase includes a 3-computer license.

Portal supports VST, VST3, AU, and AAX formats on Windows 7+ and macOS. It does not support Linux or CLAP. If you use Pro Tools, Portal's AAX support is an advantage. If you're on Linux or prefer CLAP, GRN is your only option between the two.

Who Should Buy GRN?

GRN is the right choice if you want professional granular synthesis without a steep learning curve or a steep price tag. At $29.99, it costs less than a single month of many plugin subscriptions, and you own it forever.

It's ideal for producers making ambient, lo-fi, experimental, or electronic music who want to add granular textures quickly. The randomizer means you can find interesting sounds in seconds. The scale quantization ensures those sounds stay musical. The feedback engine adds depth that goes beyond basic granular processing.

GRN is also the right choice if you're on Linux, if you need CLAP support, or if you simply prefer a focused plugin that does one thing well without burying you in parameters. If you're not sure whether granular synthesis is for you, GRN Lite (free) lets you try the core engine before committing.

Who Should Buy Output Portal?

Portal is the right choice for professional sound designers who need the deepest possible control over their granular processing. If you regularly spend hours designing individual sounds, Portal's modulation envelopes, XY macro pad, and 7-effect chain give you tools that GRN simply doesn't have.

It's also worth considering if you need AAX support for a Pro Tools workflow, if you want a massive preset library to browse (250+ vs 10), or if you're already invested in the Output ecosystem and want to add Portal to your suite through Output One ($14.99/month).

Portal makes sense when budget genuinely isn't a factor and you need every parameter exposed. For professional studios billing clients for sound design work, the $149 investment pays for itself quickly.

GRN vs Portal: Full Feature Comparison

Conclusion

GRN and Output Portal are both capable granular synthesis plugins, but they serve different producers at different price points. Portal is the more feature-rich option — it has more presets, more effects, deeper modulation, and an XY macro pad. If you need that level of control and budget isn't a concern, Portal delivers.

But for the majority of producers, GRN offers the better value. At $29.99 vs $149, you get a focused granular engine with features Portal lacks — a dedicated randomizer, scale quantization across four scale types, harmony mode, a full feedback engine with three saturation modes, and freeze mode. It runs on Linux, supports CLAP, and uses minimal CPU.

The core granular sound is comparable between the two. The question isn't which one sounds better — it's which workflow and feature set matches how you actually make music. If you want instant, musical granular textures without navigating deep menus, GRN is the better tool. If you want a granular workstation with every parameter exposed, Portal is worth the investment.

Not sure yet? Start with GRN Lite for free and see if the granular workflow clicks for you.

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