Comparison

GSDSP Quantum Delay vs Kalimba Keys

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

GSDSP Quantum Delay

This app offers a vintage-inspired stereo delay effect with advanced modulation, flexible filtering, and precise timing controls. It allows users to sculpt unique echo textures, from warm analog sounds to complex, evolving soundscapes.

Highlights
  • Vintage-inspired stereo delay
  • Deep modulation system
  • Flexible filtering (LPF, HPF, BPF)
  • Precise timing controls (BPM, ms)
  • Switchable stereo/dual mono modes
  • Advanced modulation sources (LFO, Random, Envelope)
Features
Read full description

A vintage-inspired delay supercharged with deep modulation, flexible filtering, and creative timing that pushes echoes into new dimensions. Classic Delay, Reinvented Quantum Delay takes the charm of a vintage stereo delay and fuses it with our next-level modulation system. Switch between the warm character of Tape mode and the pristine clarity of Fade mode, lock to BPM (including 5-tuplets) or dial in precise times in milliseconds. Use the Fine control for subtle push-and-pull micro-timing — or modulate your delay lines in ways traditional delays could only dream of. Sculpted Echoes Shape your repeats with switchable lowpass, highpass, and bandpass filters placed directly in the feedback path. Add modulation to create evolving tones, gentle movement, or drifting, frequency-shifting echoes. From warm analog-style rolls to shimmering, swirling textures, it’s all there. Feedback with Precision Control your delay tail behavior using either traditional % feedback or our modern dB-per-second decay system — ideal for predictable, musical decay even when the feedback path becomes complex. Enable Crossfeed for classic ping-pong stereo bounce, or push into Over-Feedback to create dense, self-building echoes that drift toward infinity. Stereo or Dual Mono Every section of Quantum Delay — delay, filter, and feedback — can switch between stereo and dual mono modes. Create tight, controlled stereo images or break them apart for wide, offset, unpredictable spaces. Dual mono modulation unlocks complex stereo interplay and beautifully asymmetric echoes. Modulation Without Limits Quantum Delay integrates our advanced modulation system, letting you modulate nearly anything: delay time, filters, feedback parameters, stereo controls, and more. Use LFOs, Random Generators, 2D modulators, Envelope Followers, Macros, and even chaotic systems to push your echoes far beyond traditional delay behavior. Or use our parameter randomisation feature to explore the plugin’s sound at random. Quantum Delay is an AUv3 audio effect plugin compatible with Logic Pro, AUM, Cubasis, GarageBand and many more. A Desktop version is also available for Windows and macOS (VST3 / AU / AAX). More information here: https://gs-dsp.com/products

About

Kalimba Keys

This app offers a realistic and expressive Kalimba instrument experience with studio-quality sound. It features detailed sampling, a variety of built-in effects, and cross-platform preset management for seamless creativity.

Highlights
  • Individually-sampled Kalimba notes
  • Multiple Kalimba sound variations
  • Modulation and Space & Time FX
  • Adjustable effects order
  • 35 included presets
  • Cross-platform preset sharing
  • Standalone app and AUv3 compatibility
Features
Read full description

Kalimba Keys is your gateway to expressive Kalimba sounds. Experience the richness of Kalimba Keys, the go-to Kalimba instrument app that brings studio-quality sound to your fingertips. Immerse yourself in authenticity with round robin and per-key sampling, allowing for genuine and nuanced playback. Elevate your compositions with essential effects, including tape-style delay, powerful stereo reverb, and versatile modulation FX (Chorus, Phaser, Flanger, Tremolo, Auto Pan). Unlock the simplicity of creativity as you save and load configurations with cross-platform presets, ensuring seamless compatibility across sessions. Enjoy the freedom of full automation control, sculpting your ideal sound effortlessly. AUv3 compatible for use with your favorite host apps like Cubasis, GarageBand, AUM, & more! Explore the world of expressive Kalimba Keys – where simplicity meets precision. Features - Individually-sampled Kalimba notes - 4X Kalimba Sounds (Original, Classic, Large, & Small) - Modulation Multi-FX: Multiple FX section with 6 modes including Chorus, Flanger, Phase, Vibrato, Tremolo, Auto Pan - Space & Time FX: Further customize your sounds with natural reverb and tape-style delay effects - Effects Pre/Post Mode: Space & Time and Modulation effects orders can be swapped. - 35 Presets include for instant playability and inspiration - Cross-platform support: presets can be shared between iOS and macOS & Windows - Preset Manager included for saving, editing, and loading different presets - Standalone app and AUv3 included

Screenshots

GSDSP Quantum Delay3 screens
Kalimba Keys3 screens

Verdict

The call

The clearest difference is price: Kalimba Keys at $4.99 against GSDSP Quantum Delay's $14.99. Kalimba Keys also leads on rating (5.0 vs 4.8). GSDSP Quantum Delay's advantage is update cadence (every 5 weeks vs every 6 months). On review sentiment, ratings volume, ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

GSDSP Quantum Delay costs $14.99 and Kalimba Keys $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Kalimba Keys holds the better App Store score, 5.0 against 4.8. Both are backed by a comparable volume of ratings — 17 and 14 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

GSDSP Quantum Delay ships an update every 5 weeks, Kalimba Keys every 6 months. The most recent releases landed on September 22, 2026 and September 7, 2026 respectively.

Scorecard3 real differences · 7 level
GSDSP Quantum Delay versus Kalimba Keys: the parameters behind the verdict, then further details
ParameterGSDSP Quantum DelayKalimba Keys
Price$14.99$4.99 — better
Rating4.8 (17 ratings)5.0 (14 ratings) — better
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings17 — better14
Update frequencyEvery 5 weeks — betterEvery 6 months
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS12.012.0
Further details — not scored
Size94 MB112 MB
Age rating4+4+
DeveloperGustav ScholdaOSC Audio

Customer experience

GSDSP Quantum Delay

All ratings17 ratings
Positive94.1%
Neutral0.0%
Negative5.9%
Written reviews4 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Kalimba Keys

All ratings14 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

GSDSP Quantum Delay

No in-app purchases

None

Kalimba Keys

No in-app purchases

Questions

Is GSDSP Quantum Delay free?
GSDSP Quantum Delay costs $14.99, with no in-app purchases.
Is Kalimba Keys free?
Kalimba Keys costs $4.99, with no in-app purchases.
Which has better reviews, GSDSP Quantum Delay or Kalimba Keys?
Kalimba Keys is rated higher. GSDSP Quantum Delay averages 4.8 out of 5 from 17 ratings, while Kalimba Keys averages 5.0 from 14 ratings.
Do GSDSP Quantum Delay or Kalimba Keys have ads?
Neither GSDSP Quantum Delay nor Kalimba Keys shows ads.
Which is updated more often, GSDSP Quantum Delay or Kalimba Keys?
GSDSP Quantum Delay ships an update every 5 weeks, and Kalimba Keys every 6 months. Most recently, GSDSP Quantum Delay was updated on September 22, 2026 and Kalimba Keys on September 7, 2026.

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