iVCS3 vs OB
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
iVCS3
This application emulates the iconic EMS VCS3 synthesizer, a pioneering portable synthesizer from 1969. It recreates the original's unique sound generation capabilities, including its oscillators, filters, and patch matrix, allowing users to explore its distinctive sonic palette.
- Official EMS VCS3 emulation
- Three oscillators (2 VCOs, 1 LFO)
- Noise generator
- Voltage controlled low pass filter (VCF)
- Patch board matrix
- Joy-stick controller
- Voltage controlled spring reverb
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iVCS3 Official EMS VCS3 emulator The VCS3 was created in 1969 by Peter Zinovieff's EMS company. The electronics were largely designed by David Cockerell and the machine's distinctive visual appearance was the work of electronic composer Tristram Cary. The VCS3 was more or less the first portable commercially available synthesizer—portable in the sense that the VCS 3 was housed entirely in a small, wooden case. The VCS3 was quite popular among progressive rock bands and was used on recordings by The Alan Parsons Project, Jean Michel Jarre, Hawkwind, Brian Eno (with Roxy Music), King Crimson, The Who, Gong, and Pink Floyd, among many others. Well-known examples of its use are on The Who track "Won't Get Fooled Again" (as an external sound processor, in this case with Pete Townshend running the signal of a Lowrey Organ through the VCS3's filter and low frequency oscillators) on Who's Next. Pink Floyd's "On the Run" (from The Dark Side of the Moon) made use of its oscillators, filter and noise generator, as well as the sequencer. Their song Welcome to the Machine also used the VCS3. The bassy throb at the beginning of the recording formed the foundation of the song, with the other parts being recorded in response. The VCS3 was also a staple at the BBC’s Radiophonic Workshop, and was a regular (and most frightening) sound generator for the Dr Who TV series. Many fo the monsters and atmoshere;s created for the show came directly from the VCS3. Description The VCS3 has three oscillators (in reality, the first 2 oscillators are normal oscillators and the 3rd an LFO or Low Frequency Oscillator), a noise generator, two input amplifiers, a ring modulator, a 18dB/octave (pre-1974) or 24dB/octave (after 1974) voltage controlled low pass filter (VCF), a trapezoid envelope generator, joy-stick controller, voltage controlled spring reverb unit and 2 stereo output amplifiers. Unlike most modular synthesizer systems which use cables to link components together, the VCS3 uses a distinctive patch board matrix into which pins are inserted in order to connect its components together. Keyboards controller DK1 keyboard controller Although the VCS3 is often used for generating sound effects due to lack of built-in keyboard, there were external keyboard controllers for melodic play. The DK1 in 1969 was an early velocity sensitive monophonic keyboard for VCS3 with an extra VCO and VCA. Later it was extended for duophonic play, as DK2, in 1972. Also in 1972, Synthi AKS was released, and its digital sequencer with a touch-sensitive flat keyboard, KS sequencer, and its mechanical keyboard version, DKS, were also released. (See: en.wikipedia.org/wiki/VCS3)
OB
This app emulates the classic Oberheim OB-X synthesizer, offering its rich sound and behavior with added enhancements. It focuses on sonic quality and includes micro random detuning for authentic analog warmth. External effects are recommended to further shape its versatile soundscapes.
- Oberheim OB-X emulation
- Recreates original sound and behavior
- Added enhancements to original design
- Micro random detuning
- Rich and good sound quality
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OB-Xd is based on the Oberheim OB-X. It attempts to recreate its sound and behavior, but as the original was very limited in some important ways, a number of things were added or altered to the original design. OB-Xd was designed to sound as good and as rich as the original. It implements micro random detuning. Also, like many synths of the OB-X's generation, the OB-Xd has no internal effects so its sounds and textures can be greatly enhanced by the use of additional processing like chorus, reverb, delay, etc.
Screenshots
Verdict
The clearest difference is in-app purchases: OB at none against iVCS3's 10. OB also leads on price ($14.99 vs $19.99) and iOS requirement (15.0 vs 17.0). iVCS3's advantage is review sentiment (91% vs 57%) and rating (4.9 vs 4.4). On update cadence, ads and device support 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
iVCS3 costs $19.99 and OB $14.99 up front. iVCS3 sells 10 one-off in-app purchases. OB asks for nothing beyond the download.
iVCS3 holds the better App Store score, 4.9 against 4.4. Both are backed by a comparable volume of ratings — 206 and 65 respectively. Written reviews point the same way: 91% of iVCS3's written reviews are positive against 57% of OB's.
Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on October 21, 2026 and October 15, 2026 respectively.
| Parameter | iVCS3 | OB |
|---|---|---|
| Price | $19.99 | $14.99 — better |
| Rating | 4.9 (206 ratings) — better | 4.4 (65 ratings) |
| Positive reviews | 90.7% of reviews — better | 57.0% of reviews |
| Number of ratings | 206 — better | 65 |
| Update frequency | Every 2 months | Every 2 months |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | Free — better |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 17.0 | 15.0 — better |
| Further details — not scored | ||
| Size | 107 MB | 25 MB |
| Age rating | 4+ | 4+ |
| Developer | apeSoft | DiscoDSP LLC |
Customer experience
iVCS3
OB
User reviews
iVCS3
From 206 App Store ratingsWhat we love
- 🚀 Faithful recreation of the original
- 👍 Powerful and versatile sound
- 🎨 Gorgeous vintage interface
- 💡 Additional features beyond the original
- 🎛️ Excellent integration with MIDI and other apps
Room to improve
- 🐛 Occasional crashes and bugs
- 🤔 Steep learning curve
- 🔍 Difficult to navigate the matrix
OB
From 65 App Store ratingsWhat we love
- 🎶 Incredible sound quality
- ✨ Inspiring creative tool
- 🎹 Faithful emulation of classic synth
- 🎛️ Great for programming
- 🎚️ Useful presets
Room to improve
- 🐛 Unusable UI on older devices
- 💻 Poor GUI scaling on iPad Pro
- 🎛️ Controls unresponsive or misaligned
- 📉 Limited functionality without updates
- 🤷♂️ No clear upgrade path
Bugs and requests
iVCS3
Reported bugs
3 issues- Presets not loading
- Crashes on iOS 15.04
- Sampler not functioning properly
Requested features
3 requests- Mac compatibility
- Improved preset management
- Expanded sampling capabilities
OB
Reported bugs
13 issues- Crashes in Audiobus
- Cannot use in MIDI section of Audiobus
- Preset browser issues (scrolling, cut off banks)
- Automation bug with cutoff freq
- UI issues on iPad Pro (buttons misaligned, text cut off)
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- App suspends on iOS 14
- No virtual keyboard in standalone app
- AUv3 crashes when adding second instance
- UI messed up in AU
- Knobs don't line up with display
- Wonky controls
- Programmer page without menu, cannot save/open patches
- LFOing filter cutoff jerky
Requested features
19 requests- Add last/high priority for mono patches
- Increase polyphony to 8 voices
- MIDI Learn functionality
- Preset browser improvements (categories, scrolling)
- Adjustable keyboard size
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- GUI scaling/layout redesign for iPhone
- Skins for GUI
- MIDI keyboard in standalone mode
- Effects
- Preset manager
- Zoom functionality for AUv3 on iPhone
- Fix knob turning bugs
- Add patch select in DAW apps
- GUI color scheme options
- Manual in settings
- Import presets
- Layering sounds (like original OBXa)
- White pinstripes on blue background (cosmetic)
- Mod wheel customization
In-app purchases
iVCS3
- Red Sky Lullaby - 180 PresetsFree
- Singe Difficile by RUST(i)KFree
- RUMBLEFree
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- OLD GRIT - COLLECTIONFree
- JEC 2018 Iconic PinkFloydFree
- JEC EMS-50Free
- SINAPSYA - Under The Dust$2.99
- LALA - Sonic Pleasures$3.99
- JEC Mega Bank$4.99
- Essential EMS Modifications$6.99
OB
No in-app purchases








