# AudioKit Digital D1 Synth vs Spectrum Synthesizer Bundle

The clearest difference is in-app purchases: Spectrum Synthesizer Bundle at none against AudioKit Digital D1 Synth's 6. Spectrum Synthesizer Bundle also leads on ads (none vs shown) and review sentiment (93% vs 76%). AudioKit Digital D1 Synth's advantage is ratings volume (2.1K vs 135). On price, rating and update cadence there is nothing between them.

Both are free to download. AudioKit Digital D1 Synth sells 6 in-app purchases, starting at $4.99 per 7 days. Spectrum Synthesizer Bundle asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 4.8 for AudioKit Digital D1 Synth against 4.8 for Spectrum Synthesizer Bundle. That said, the two scores are not equally well evidenced: AudioKit Digital D1 Synth has 2.1K ratings behind it against 135, so its average is the more settled of the two. Written reviews are what separate them: 76% of AudioKit Digital D1 Synth's written reviews are positive against 93% of Spectrum Synthesizer Bundle's.

AudioKit Digital D1 Synth ships an update every 3 weeks, Spectrum Synthesizer Bundle every 4 weeks. The most recent releases landed on November 2, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | AudioKit Digital D1 Synth | Spectrum Synthesizer Bundle |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.8 (2.1K ratings)](https://appshunter.io/ios/app/audiokit-digital-d1-synth/id1436905540/reviews) | **[4.8 (135 ratings)](https://appshunter.io/ios/app/spectrum-synthesizer-bundle/id1467384251/reviews)** |
| Number of ratings | **2.1K** | 135 |
| Positive reviews | 76.1% of reviews | **92.9% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 3 weeks** | Every 4 weeks |
| Monetization | Subscription | **Paid** |
| Size | 636 MB | 13 MB |
| Requires iOS | 13.0 | **11.0** |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Audiobus Pty Ltd](https://appshunter.io/developer/672585101) | [Thomas Burns](https://appshunter.io/developer/522224284) |

## What reviewers say

### AudioKit Digital D1 Synth

[App page](https://appshunter.io/ios/app/audiokit-digital-d1-synth/id1436905540)

This app is a virtual analog and PCM synthesizer for iPad, inspired by the digital synthesizers of the 80s and 90s. It offers a vast library of presets, advanced synthesis features, and built-in effects for creating rich, retro-inspired sounds.

**Highlights:** 64-voice hybrid digital poly synthesis, 1GB+ of original samples, Stand-alone, IAA, and AUv3 support, Vintage-style arp/step sequencer, 3 LFOs with fun routings, Dual independent per-layer filters, Built-in FX suite

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly premium | $4.99 | per 7 days |
| Weekly premium | $4.99 | per 7 days |
| Yearly premium | $9.99 | per year |
| Yearly premium | $9.99 | per year |
| D1 PCM Expansion-01 | Free | one-time |
| Platinum Expansion PCM EXP-01 | Free | one-time |

**What reviewers like**

- 🎨 Excellent sound quality
- 🎹 Versatile and inspiring presets
- 👍 Intuitive and user-friendly interface
- 💰 Great value for the price
- 🔥 Cutting-edge digital synthesis

**What reviewers complain about**

- 🐛 Occasional crashes and stability issues
- 🔋 High battery consumption
- 🔒 Lack of Audio Unit (AUv3) support
- 🤔 Some presets not easily usable
- 🕰️ Slow loading times in certain DAWs

**Reported bugs**

- Presets not loading correctly
- MIDI note dropouts and latency
- Crashes when used with certain DAWs
- Compatibility issues with newer iOS versions

**Requested features**

- Add Audio Unit (AUv3) support
- Improve MIDI integration and responsiveness
- Implement a built-in recording/sampling feature
- Expand preset library with more genres and styles
- Add more sound design controls and modulation options


### Spectrum Synthesizer Bundle

[App page](https://appshunter.io/ios/app/spectrum-synthesizer-bundle/id1467384251)

This app provides a bundle of four professional audio unit synthesizers and one effect, inspired by popular eurorack modules. Explore diverse sound design possibilities with multi-mode oscillators, modal synthesis, string generation, and granular sampling. Compatible with DAWs and AU hosts for creative music production.

**Highlights:** Multi-mode polyphonic oscillator, Modal synthesis, String generation algorithms, Granular sampler and looper, Modulation LFO and ADSR envelope, XY touchpad and modulation matrix

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

**In-app purchases:** none

**What reviewers like**

- ✨ Incredible sound quality
- 🎶 Deep modulation capabilities
- 💡 Distinct and unique character
- 🌊 Excels at fluid soundbeds
- 🎹 Great for MIDI keyboard use

**What reviewers complain about**

- 🐛 Crashes more than it should
- ⚠️ Description misleading (granular synth missing)
- 🐛 Modal synthesizer doesn't work alone
- 💥 Creates massive feedback on macOS
- ❌ UI stripped down

**Reported bugs**

- Crashes more than it should
- Modal synthesizer doesn't work on its own
- Creates massive feedback on macOS
- Songs won't export from GarageBand iOS when plugin is enabled
- Lots of crashes since previous update

**Requested features**

- Bring back granular synth or remove from description
- Create a standalone version
- Bring back old UI as an option
- Advanced version with standalone apps, proper GUI, and extensive modulation/control
- More Mutable ports (Ripples, Stages)


## Frequently asked questions

### Is AudioKit Digital D1 Synth free?

AudioKit Digital D1 Synth is free to download, with in-app purchases available.

### Is Spectrum Synthesizer Bundle free?

Spectrum Synthesizer Bundle is free to download, with no in-app purchases.

### Which has better reviews, AudioKit Digital D1 Synth or Spectrum Synthesizer Bundle?

Spectrum Synthesizer Bundle is rated higher. AudioKit Digital D1 Synth averages 4.8 out of 5 from 2.1K ratings, while Spectrum Synthesizer Bundle averages 4.8 from 135 ratings.

### Do AudioKit Digital D1 Synth or Spectrum Synthesizer Bundle have ads?

AudioKit Digital D1 Synth shows ads; Spectrum Synthesizer Bundle does not.

### Which is updated more often, AudioKit Digital D1 Synth or Spectrum Synthesizer Bundle?

AudioKit Digital D1 Synth ships an update every 3 weeks, and Spectrum Synthesizer Bundle every 4 weeks. Most recently, AudioKit Digital D1 Synth was updated on November 2, 2026 and Spectrum Synthesizer Bundle on November 3, 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.*