CVOsc turns your iPad, iPhone, or Android device into a real-time oscilloscope for up to 16 channels of Eurorack Control Voltage or audio-rate signal. Capture from any DC offset enabled soundcard, overlay channels, record, and play back through DC-coupled outputs — all with per-channel scaling and live tuning detection.
Everything you need to inspect modular signals the way a bench scope would, plus the recording and tuning tools audio interfaces usually don't give you.
Stream every input on a DC offset enabled soundcard simultaneously. iPad and Android tablets show a 4×4 grid; iPhone and Android phones show a 2×2 grid and page through the rest.
Flip each channel between CV and audio-rate handling. CV uses volts with a 1 s time base; audio uses normalized amplitude with a rising zero-crossing trigger.
Capture any selected channels to per-channel CAF / WAV files with a JSON sidecar alongside the audio for signal type, scaling, sample rate, and timestamp metadata.
Assign each recording to an output channel and play it back through your interface. CVOsc checks the device against a catalog of known DC-coupled hardware before enabling Play.
Autocorrelation for audio, V/oct mapping for CV. Each selected pane shows the detected note and cents offset, so you can tune a VCO or quantizer against the scope.
Set the vertical range, DC offset, and time base on any channel. Units render in your locale (±10.00 V or ±10,00 V), and the trigger can be toggled per channel.
Pick the view that fits what you're chasing — an overview across every input, a focused look at just the ones you care about, or a stacked overlay for comparing shape.
A uniform grid of every input the interface exposes. Pages through 16-at-a-time on iPad or 4-at-a-time on iPhone. Tuning badges render per pane when enabled.
Only the channels you've picked, in the same uniform grid layout. Great for isolating a patch section or a subset of CV outs without losing per-pane scaling.
Selected channels drawn on top of each other in a single pane. Perfect for comparing phase, lining up envelopes, or checking that two VCOs track.
Plug a DC offset enabled soundcard into your device over USB (class-compliant USB audio on both iOS and Android).
Tap a pane to set signal type, range, offset, and time base for that channel.
Select channels, tap Record, and CVOsc writes per-channel audio plus a JSON sidecar to local storage.
Assign each recording to an output and replay through a DC-coupled channel on your interface.
CVOsc works with any class-compliant USB audio interface. Audio-rate capture works on every device; to see and play back CV you need a DC offset enabled soundcard. CVOsc ships with a built-in catalog of units known to preserve DC.
Grab it on your platform of choice. The iOS build covers iPad and iPhone from a single App Store listing; Android is a separate build on Google Play.
To see CV signals you need a DC offset enabled soundcard — an audio interface whose inputs and outputs preserve DC instead of stripping it. For audio-only work, any class-compliant USB audio interface will do. On iPad you can either use a USB-C iPad directly or a Lightning iPad with an Apple Camera Adapter. On Android, any device with USB Host support works.
Debug builds of the Android app fall back to a synthetic 8-channel sine generator when no USB interface is attached, so you can drive the UI without hardware. The App Store release always requires a real USB audio interface to show real signals.
Recordings live in the app's local storage on your device — in the sandboxed Documents directory on iOS, and in scoped app storage on Android. They stay on-device until you delete them or uninstall the app.
Yes. For audio-rate signals CVOsc runs autocorrelation on the last 2048 samples. For CV channels it averages the voltage and maps it under the 1 V/oct convention (0 V = C0). The badge shows the detected note and cents offset, and the cents label turns violet when the offset exceeds 10 cents.
iPadOS and iOS from the Apple build (iPadOS / iOS 26.4+), and Android 7.0 (SDK 24) and newer from the Google Play build. Same core engine, same feature set; iPad is the primary target.
On Android, the Tuner and Record/Playback features are unlocked via one-time in-app purchases through Google Play Billing. The Apple build ships with all features included.
Most audio interfaces strip DC from their outputs, which destroys CV. CVOsc ships a catalog of DC offset enabled soundcards known to preserve DC through their outputs. If your current output isn't in the catalog, the Play button is disabled and the app tells you why.
No. CVOsc does not collect, transmit, sell, or share any personal data. Recordings stay on your device. See the Privacy Policy for details.