Comparison

GSDSP Quantum Delay vs VAPolyMkII

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

VAPolyMkII

This virtual analog synthesizer offers a 16-voice bitimbral polyphonic sound engine with two distinct filter models and extensive modulation options. It includes a built-in sequencer, various effects, and supports AudioUnit Extension for integration with DAWs. Projects can be synced across iPhone, iPad, and Mac via iCloud.

Highlights
  • 16-voice bitimbral polyphonic synthesizer
  • Two analog-modeled filter types
  • Extensive modulation capabilities
  • Built-in piano roll sequencer
  • Multiple audio effects
  • AudioUnit Extension (AUv3) support
  • iCloud Drive project syncing
Features
Read full description

VAPolyMkII is a virtual analog bitimbral polyphonic synthesizer for iPhone, iPad and Mac. It features 16 voice synthesizer, effects, sequencer and audio visualization tools. It operates as a stand alone or as an AudioUnit Extension (AUv3). Stand Alone supports Ableton Link, MIDI and audio file export. The synthesizer consists of two 8 voice synthesizer, which features two oscillators, two ADSR envelopes, resonant high pass and low pass filter and an amplifier per voice. The oscillators features continuously variable wave shape and wide variety of modulation. The filters are modeled on the Sallen-Key filter circuit and cascaded OTA filter circuit for classic analog sound. The Effects include delay, chorus, flanger, reverb, eq and compressor. The sequencer features piano roll and parameter automation editor to program 16 bar pattern per clip. Project files can be saved in iCloud Drive, so that the project can be accessed from iPhone, iPad or Mac. - Main Features - Virtual analog 16 voice bitimbral polyphonic synthesizer Two type of Lowpass filter, cascaded OTA model and Sallen-key model. Patch points for modulation. Support MIDI 2.0 New User Interface built by SwiftUI for improved performance. Built-in Sequencer. 16 bar patterns per clip. Total 8 clips. Piano Roll and Parameter automation. Support Audio Unit Extension (AUv3) Works on iPhone, iPad and Mac. Support iCloud Drive to share project files between the platforms. Audio Export. Linear PCM format (AIFF, WAV and CAF) and compressed format (AAC) Support Ableton Link, Bluetooth MIDI, MIDI In / Out. - System Requirements - A13 Fusion or above is recommended. AudioUnit Extension (AUv3) requires host application which support AudioUnit Extension. AudioUnit Extension is supported by Apple Logic and Apple Garage Band on iOS and macOS. For any other DAW, it depends on the application and some of them don’t support AudioUnit Extension.

Screenshots

GSDSP Quantum Delay3 screens
VAPolyMkII4 screens

Verdict

The call

The clearest difference is review sentiment: GSDSP Quantum Delay at 100% against VAPolyMkII's 67%. GSDSP Quantum Delay also leads on rating (4.8 vs 4.5) and iOS requirement (12.0 vs 16.6). VAPolyMkII's advantage is update cadence (weekly vs every 5 weeks). On price, 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 VAPolyMkII $14.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

GSDSP Quantum Delay holds the better App Store score, 4.8 against 4.5. Both are backed by a comparable volume of ratings — 17 and 11 respectively. Written reviews point the same way: 100% of GSDSP Quantum Delay's written reviews are positive against 67% of VAPolyMkII's.

UpkeepUpdate frequency

GSDSP Quantum Delay ships an update every 5 weeks, VAPolyMkII weekly. The most recent releases landed on September 22, 2026 and September 20, 2026 respectively.

Scorecard4 real differences · 6 level
GSDSP Quantum Delay versus VAPolyMkII: the parameters behind the verdict, then further details
ParameterGSDSP Quantum DelayVAPolyMkII
Price$14.99$14.99
Rating4.8 (17 ratings) — better4.5 (11 ratings)
Positive reviews100.0% of reviews — better66.7% of reviews
Number of ratings17 — better11
Update frequencyEvery 5 weeksWeekly — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, Mac
Requires iOS12.0 — better16.6
Further details — not scored
Size94 MB16 MB
Age rating4+4+
DeveloperGustav ScholdaRyo Togawa

Customer experience

GSDSP Quantum Delay

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

VAPolyMkII

All ratings11 ratings
Positive90.9%
Neutral0.0%
Negative9.1%
Written reviews3 reviews
Positive66.7%
Neutral0.0%
Negative33.3%

In-app purchases

None

GSDSP Quantum Delay

No in-app purchases

None

VAPolyMkII

No in-app purchases

Questions

Is GSDSP Quantum Delay free?
GSDSP Quantum Delay costs $14.99, with no in-app purchases.
Is VAPolyMkII free?
VAPolyMkII costs $14.99, with no in-app purchases.
Which has better reviews, GSDSP Quantum Delay or VAPolyMkII?
GSDSP Quantum Delay is rated higher. GSDSP Quantum Delay averages 4.8 out of 5 from 17 ratings, while VAPolyMkII averages 4.5 from 11 ratings.
Do GSDSP Quantum Delay or VAPolyMkII have ads?
Neither GSDSP Quantum Delay nor VAPolyMkII shows ads.
Which is updated more often, GSDSP Quantum Delay or VAPolyMkII?
GSDSP Quantum Delay ships an update every 5 weeks, and VAPolyMkII weekly. Most recently, GSDSP Quantum Delay was updated on September 22, 2026 and VAPolyMkII on September 20, 2026.

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