Kauldron Synthesizer vs SynthScaper LE
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Kauldron Synthesizer
This app combines classic analog synth warmth with AI-powered sound design. It offers intelligent preset generation, extensive modulation options, and a powerful arpeggiator for creating rich synth textures.
- AI-powered preset generation (SPAWN²)
- Analog modeling oscillators
- Extensive modulation matrix
- Dual XY-pads for control
- Powerful arpeggiator
- AUv3 plugin support
- Over 900 presets
Read full descriptionHide full description
Kauldron is where classic warmth meets Artificial Intelligence. One of our toniest and punchiest synths, Kauldron features a completely new analog modeling technology. The full spectrum of rich synth textures is bolstered by the groundbreaking SPAWN intelligent preset generation system that allows new patches to be created at the touch of a button. Abounding with pure hard-hitting tones, Kauldron requires little to no FX or production gimmicks to sound big. Kauldron is designed with modulation and fine dynamic control in mind. The two fully-featured LFOs and the mod envelope combine with a wide variety of MIDI learnable controls to manipulate multiple parameters. Everything is easily set up in a clearly laid out ‘mod matrix.’ The dual XY-pads can be used for controlling modulation or a wide range of synth parameters. MIDI aftertouch can be routed via the matrix for even greater control over expression and tonality. Kauldron also debuts the next generation of our Artificial Intelligence preset creation system, SPAWN². Completely reimagining the groundbreaking SPAWN algorithms in our hugely popular Magellan, the new SPAWN² gives you unprecedented control over generating presets. In the expert mode, you can accomplish anything from subtle ‘variations on a theme’ to bold new sounds. In the basic mode, where Kauldron does all the thinking, you get preset after usable preset with just a touch. This is not simple randomization: it is the power of A.I. put to benevolent use! Kauldron also includes its AUv3 plugin version so that you can seamlessly run multiple instances in your favorite DAW. Powerful arp with both live & program modes; comprehensive MIDI features with effortless MIDI learn; over 900 presets; recording, sharing, these are just some of the features brewing inside Yonac’s Kauldron. Selected specs include, SYNTH • 3 analog modeling oscillators w/ multiple waveforms & true PWM • FM via Osc 2 • Maximizer module with drift, spread & voice count for huge, stereophonic all-synth sounds • New vAnalog filter design w/ ‘dirt’ overload for even warmer, harmonically complex tones • Dedicated filter ADSR envelope • Filter tracking, contour & more • Pink/white noise generator • Osc. phase reset & sync • Retro & modern glide algorithms • Virtual VCA envelope with 2 attack types • Poly/mono operation • Legato mode for buttery smooth passages • Extensive modulation options via the ‘mod matrix’ • 2 LFOs w/ BPM sync, keytracking, trigger mode & more • Assignable mod envelope • 23 mod targets • 11 mod controllers, including aftertouch, velocity & keytracking • 2 XY-Pads for controlling mod targets or synth parameters • Arpeggiator with live & program modes, 11 algorithms, gate, swing, note value, octaving & more • Stereo mod effect with chorus & flanger modes • BPM-syncable stereo delay • Studio quality reverb w/ 7 room types, damping, time & mix • 900+ presets in a wide variety of styles & sounds SPAWN² • Automatic preset generation via artificial intelligence • Generate infinite new, usable presets at the touch of a button • Expert mode lets specify Variation & Autonomy for each major synth module • 3 unique A.I. algorithms • Auto arp programming in any listed scale PRO FEATURES • AUv3 - use as Audio Unit instrument plugin on iPad & iPhone • Fullscreen AU mode • Extensive MIDI: MIDI learn, aftertouch, MIDI CC map save/share, KB mapping, program changes & more APP • iPhone & iPad Compatibility • Powerful YPAT2 preset management system • Classic or ribbon key controller • Ribbon controller: Poly aftertouch into Kauldron • Ribbon controller: Settable musical key & scale • Classic KB: Velocity w/ sensitivity setting • Tapedeck: Record, loop & share • Metronome • Tap BPM
SynthScaper LE
Create lush pads, psychedelic synths, and atmospheric soundscapes with a powerful, easy-to-use sound engine. Design unique multi-timbral scenes with three independent generators, a spatial mixer, and a versatile screen keyboard. Supports MIDI controllers and works standalone or with DAWs.
- Multitimbral sound engine
- Three independent sound generators
- Spatial mixer with reverb simulation
- Advanced screen keyboard with continuous tone control
- Sequencer/arpeggiator per generator
- Full MIDI keyboard and controller support
- AUv3 and Inter-App audio compatible
Read full descriptionHide full description
Lush pads, psychedelic synths and atmospheric soundscapes in an easy to use app with a powerful sound engine. SynthScaper LE has three independent sound generators in which you can use various presets from the large built-in library and create unique multi-timbral sound scenes. You can tune the general parameters that define the character of the sound of each generator and place them in a common sound space with the spatial mixer. The spatial mixer simulates two types of reverberating space in which you define the distance and position from the sound generator to the listener, the dimension of the space and amount of reflections. Use the "Random" option to get new ideas for your unique sound scenes. This option generates a new scene from existing presets and sets the generators' parameters to random values. Next you can adjust them to polish your special sound. The screen keyboard in addition to standard use has a special mode that turns it into a continuous area in which you can smoothly change the tone separately for each touch. This is ideal for creating a variety of soundscapes, drones and textures. The screen keyboard also has a simulation of velocity, adjustment of pitch and the rate of modulation, as well as a scale editor with a built-in list of scales. Each sound generator has its own sequencer / arpeggiator, so you can create a common sequence for all generators or separate sequences for each. Many different modes allow you to turn even the simplest sequence into a continuously varying melody changing just by pressing a single note. You can also record a sequence from the keyboard or copy it from other scenes. SynthScaper LE fully supports MIDI keyboards and controllers and can assign external MIDI controls to almost all parameters. You can assign sound generators to different ranges on your MIDI- and on-screen keyboard, and even only to MIDI or only to the screen keyboard. In addition, this app can auto detect the type of MIDI keyboard and automatically use extended controls such as knobs and buttons. For a list of supported MIDI keyboards and assigned controls see the app description. This app can work as standalone and can be used with any audio host or DAW apps that support AUv3 or Inter-App audio connection. SynthScaper LE is completely compatible with the full-featured advanced version SynthScaper and can import scenes packs created in the advanced version. Video demo: https://youtu.be/CNwVbW26s5o You can find more details about SynthScaper LE on the website: https://motion-soundscape.blogspot.com
Screenshots
Verdict
The clearest difference is update cadence: SynthScaper LE at every 3 weeks against Kauldron Synthesizer's every 49 months. SynthScaper LE also leads on price ($4.99 vs $9.99) and iOS requirement (11.0 vs 15.6). Kauldron Synthesizer's advantage is ratings volume (136 vs 24). On rating, review sentiment, 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
Kauldron Synthesizer costs $9.99 and SynthScaper LE $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.
On the App Store both sit at effectively the same score — 4.6 for Kauldron Synthesizer against 4.7 for SynthScaper LE. That said, the two scores are not equally well evidenced: Kauldron Synthesizer has 136 ratings behind it against 24, so its average is the more settled of the two. Written reviews are what separate them: 80% of Kauldron Synthesizer's written reviews are positive against 73% of SynthScaper LE's.
Kauldron Synthesizer ships an update every 49 months, SynthScaper LE every 3 weeks. The most recent releases landed on October 20, 2026 and October 24, 2026 respectively.
| Parameter | Kauldron Synthesizer | SynthScaper LE |
|---|---|---|
| Price | $9.99 | $4.99 — better |
| Rating | 4.6 (136 ratings) | 4.7 (24 ratings) — better |
| Positive reviews | 79.7% of reviews — better | 72.7% of reviews |
| Number of ratings | 136 — better | 24 |
| Update frequency | Every 49 months | Every 3 weeks — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Paid |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.6 | 11.0 — better |
| Further details — not scored | ||
| Size | 32 MB | 94 MB |
| Age rating | 4+ | 4+ |
| Developer | Yonac Inc. | Igor Vasiliev |
Customer experience
Kauldron Synthesizer
SynthScaper LE
Bugs and requests
Kauldron Synthesizer
Reported bugs
15 issues- Oscillators cannot be set to -1 octave
- Shrill noise
- No Bluetooth speaker output
- Fails to reload with Logic projects
- Cannot load into Logic Pro
Show 10 moreShow fewer
- Starts and quits on latest iOS
- AUv3 bug: receives notes regardless of track selection
- AUv3 implementation flaky, random crashes
- AUv3: plays all instances simultaneously
- Bug with Garageband: duplicates patterns
- MIDI learn functions not saved
- Sometimes glitchy
- XY pad movements not recorded as automation
- CPU killer on iPad 4
- No function to share sounds
Requested features
11 requests- Bring synths/effects to macOS
- Mac App version
- More comprehensive FX section (distortion/saturation)
- MIDI-out for arpeggiator
- Drum machine, PAD launcher, DAW
Show 6 moreShow fewer
- Browser download feature
- Sequencer in Kauldron
- Effects tool
- Version history
- More developer responses/support
- Dark mode option
SynthScaper LE
Not enough reviews yet to summarise bugs or requests.
In-app purchases
Kauldron Synthesizer
No in-app purchases
SynthScaper LE
No in-app purchases
Questions
Is Kauldron Synthesizer free?
Is SynthScaper LE free?
Which has better reviews, Kauldron Synthesizer or SynthScaper LE?
Do Kauldron Synthesizer or SynthScaper LE have ads?
Which is updated more often, Kauldron Synthesizer or SynthScaper LE?
Other comparisons















