A creative bass synth sequencer for creating electro melodies or dirty phat & funky acid techno 303 style basslines.
Inspired by the acid house music scene. An IOS exclusive, compared to a modern equivalent to Rebirth (Rebirth was a popular tb - 303 clone a decade ago).
Look at the video tutorial for a how-to guide. Listen to what you can create easily with 2XB303.
Create electro, house, techno, edm or synth sequences using standard step functions as seen on various sequencers like the Roland SH 101 synthesizer. Your synth sequences can also be generated randomly.
Easily capture whatever you hear and export to AudioShare, Audio-Copy, Email or iTunes Shared Folder.
Support for Audiobus 3 routing, Ableton Link, IAA (Inter App Audio)
Tweaking cut-off & decay Env-Mod & glide & accent etc for that classic sweet-spot acid growl Tap to dials to swipe up & down for fine adjustment of knobs.

The sound was first compared to a Cyclone TT - 303 synthesizer & tweaked to extend sound shaping beyond a just bass maker. Waves have optional harmonic version, noise, LFO, glide speed & PHAT/ BASS, and great effects. This is designed to give more electro music creativity beyond an acid synth 303 bass maker to create dynamically fluctuating overlaying electronic patterns. A good addition to any electro, drum and bass, acid, techno, house and any other EDM fans

Use the keyboard for the following cool tricks:
[Sequence/Control/Transpose]: Transpose both channels simultaneously while playing.
[Sequence/Control/Pattern]: Instantly switch to a saved sequence while playing. Keys correspond to stored program numbers, starting from the current program thats loaded (key 1 is your current program, key 2 is current program+1). Highlighted keys show stored programs. This is great for building up live tracks, or instant crossfading between programs. You can also "Hold settings" so it locks settings like effects.

METRONOME: Toggle drum beats -better than tick-tocks to accompany your bass lines

LFO auto control low pass CUT-OFF and/or PITCH. The pitch level can give a vintage synthesiser effect subtly detuning with low SPEED or faster for chaotic random pitches.

EFFECTS (Global/master are in yellow.)
OVERDRIVE, COMPRESSION adjusts threshold, ratio, & gain. This is a global effect.
ECHO tempo synced with feedback & wetness.
SAVE ALL. When not playing, save to memory.

Ableton Link syncs with apps .Enable for precise timing without syncing. Press LINK button at the bottom for settings.
MIDI sync with External, Virtual or Audiobus. 2XB 303 can be master or slave. ( any simple class-compliant USB should work but some may need to be power assisted)
Virtual MIDI In is always on. If you send from another app AND receive MIDI clock then you will be receiving both MIDI CLOCKS. Choose only one unless you want double tempo (which can be interesting).
While Ableton Link is enabled you can send clock. This means you can use one app to control 2XB303 synth alongside external hardware sequencers
MIDI note data is sent out on each channel

Record a fixed length, default to 32 steps. Can be changed in settings.
Arming the sampling with CAPTURE (flashing). Starts at counter 1 (ON).
PLAY CAP to listen to your super cool sampled acid synthesiser loop.

Audiobus 3 and IAA (Inter App Audio) Support. Route audio to mix or record into other applications
Audio can be routed via IAA into apps like Apple's Garageband.
Garageband will also sync your sequence for excellent multi-track recording.

To save you press "Save all", it then flashes. Now choose destination ("!" means its occupied ) then press "Save All" to confirm.

What’s New

Version 2.2

Added support for Bluetooth headphones and speakers.
Previous updates:
Too fix a possible conflict in the Audiobus and Inter-App-Audio nodes. This could cause the nodes from not showing up or behaving properly in some apps.
Last update:
A consolidated list of app updates all rolled into one taken from the sister app 6X806 Noise Drum Synth:
BPM increments now give increments of 1 for single tap or 5 with a double tap.
Captured audio loops exported to Audioshare and Email now adds BPM and date/time to file name.
Better dial control: Now you should be able to swipe up and down the knob levels quicker while maintaining refine control. It also snaps to min/max levels instead of wobbling.
INIT button for quickly clearing the currently loaded pattern to start a fresh program. Found in System/Settings.
Minor update to the UI to bring style up to date with 6X806.

Ratings and Reviews

4.5 out of 5
4 Ratings

4 Ratings

Madyetmellow ,

Not bad

Not bad. Since rebirth has been removed from the store and Technobox 2 won’t work on iOS11 and later there’s no other way to have 2 303s without using something like AUM or in a DAW. I could mention Rhythm and Xenon. So that’s in its favour. Sound quality is ok, but there are single box 303 emus on iOS that sound better. Troublemaker and Bassline being the best of the bunch. It’s not bad but at the moment it feels more like a toy and the sound needs a bit of work. With future updates it might get to the acid levels of rebirth or Technobox 2 which were the benchmarks as far as dual 303’s on iOS. If they got it sounding as good as BassLine with its soaking wet squelchy acid bass farts this would be the best Roland TB-303 emulator on iOS. The sound is the only thing holding this back giving it another star. Hopefully it will get further updates as it has great potential

Doesn’t sound very much like a real Roland TB-303 if I am honest, or any of the other 303 hardware clones but then you aren’t paying between £200-£1,000+ twice for hardware.

Give it a go. It’s easy enough to make sounds and work the sequencer and for some people it will sound real enough for them not to know the difference between hardware/software/analog/digital.

Updated & Edited. Knocked the score up one star as it’s nice to have a responsive developer. I look forward to future updates and adding another star as the app progresses. Pretty sure given time this could be one of the best on iOS.

Re-review - The last update has made it better and more practical and getting nice, unique sounds that I can’t get out of the standalone hardware. I got over the not being quite like the hardware sound and have found it useful and huge fun using alongside my TB3 & TB03 hardware and am now appreciating it for the differences it brings. Thanks dev. Looking forward to future updates. Not one for long reviews until now but this is has grabbed me and have found a use for it in my live stuff.


Worth getting

Good latest update 😎👍

Developer Response ,

Hi thanks for your great in depth review. I appreciate the time you put in to give feedback. I understand how you think its not entirely close to the real 303. I decided to add many more features and the engine runs through a few different filters - like a pre - split high pass, re-merged post low-pass. Kind of like a notch effect for the "phat" level. Some other had to be sacrificed for the LFO too as well as the many effects that are time synced, but as I wanted to be able to create much more than the 303 type sound from noisy drones to bleeps and all other kinds of electro sounds, I hope this was worth it. Ill always be looking to improve it where I can or add many other features by request. Thank you again

dEzholy ,

Not bad.. could be better!

Needs better control of knobs, very sluggish and unresponsive at the moment.

Tempo adjust needs to be better, not just in increments of 5.

Midi learn for controls would be great.

Hopefully will get better with updates....

Developer Response ,

Hi. I hope the latest update addresses the sluggishness. Now the dials have been reported to behaving very well. Also the BPM now goes either 1 or 5 increments.
Thank you

App Privacy

The developer, Rob Wilmot, has not provided details about its privacy practices and handling of data to Apple. For more information, see the developer’s privacy policy.

No Details Provided

The developer will be required to provide privacy details when they submit their next app update.


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