# DubFilter vs GSDSP Quantum Filter

The clearest difference is price: DubFilter at Free against GSDSP Quantum Filter's $14.99. DubFilter also leads on ratings volume (71 vs 3). GSDSP Quantum Filter's advantage is in-app purchases (none vs 1) and review sentiment (100% vs 73%). On ads and device support there is nothing between them.

DubFilter is free to download; GSDSP Quantum Filter costs $14.99 up front. DubFilter sells 1 one-off in-app purchase. GSDSP Quantum Filter asks for nothing beyond the download.

GSDSP Quantum Filter holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: DubFilter has 71 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 73% of DubFilter's written reviews are positive against 100% of GSDSP Quantum Filter's.

DubFilter ships an update every 6 months, GSDSP Quantum Filter every 5 weeks. Both last shipped on September 22, 2026.

## The numbers

| Metric | DubFilter | GSDSP Quantum Filter |
| --- | --- | --- |
| Price | **Free** | $14.99 |
| Rating | [4.7 (71 ratings)](https://appshunter.io/ios/app/dubfilter/id979648058/reviews) | **[5.0 (3 ratings)](https://appshunter.io/ios/app/gsdsp-quantum-filter/id6498711920/reviews)** |
| Number of ratings | **71** | 3 |
| Positive reviews | 73.3% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 6 months | **Every 5 weeks** |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 12 MB | 77 MB |
| Requires iOS | 17.0 | **12.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Amazing Noises](https://appshunter.io/developer/903336421) | [Gustav Scholda](https://appshunter.io/developer/1642323227) |

## What reviewers say

### DubFilter

[App page](https://appshunter.io/ios/app/dubfilter/id979648058)

This app provides a powerful dual filter with resonance and an exclusive overlap parameter. It also features a redesigned stereo sample player with LFO and scrubbing, along with extensive MIDI and file management capabilities.

**Highlights:** Dual low-pass/high-pass filter, Resonance and Overlap parameter, Stereo sample player with LFO, Scrubbing capabilities, Audiobus and Inter-App Audio support, MIDI control and file management, Preset morphing pad

**Features:** macOS Compatibility, Family Sharing, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Audio Unit Plugin Support | $1.99 | one-time |


### GSDSP Quantum Filter

[App page](https://appshunter.io/ios/app/gsdsp-quantum-filter/id6498711920)

This audio effect plugin offers analog-modeled filters with flexible routing and dynamic modulation for creative sound design. It provides extensive control over tone shaping and complex filtering with various filter types and configurations.

**Highlights:** Analog-modelled filters, 11 filter modes, Series and parallel routing, Dynamic modulation support, Stereo and dual mono modes, MIDI control integration

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is DubFilter free?

DubFilter is free to download, with in-app purchases available.

### Is GSDSP Quantum Filter free?

GSDSP Quantum Filter costs $14.99, with no in-app purchases.

### Which has better reviews, DubFilter or GSDSP Quantum Filter?

GSDSP Quantum Filter is rated higher. DubFilter averages 4.7 out of 5 from 71 ratings, while GSDSP Quantum Filter averages 5.0 from 3 ratings.

### Do DubFilter or GSDSP Quantum Filter have ads?

Neither DubFilter nor GSDSP Quantum Filter shows ads.

### Which is updated more often, DubFilter or GSDSP Quantum Filter?

DubFilter ships an update every 6 months, and GSDSP Quantum Filter every 5 weeks. Most recently, DubFilter was updated on September 22, 2026 and GSDSP Quantum Filter on September 22, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*