Loopy Pro: Create music, your way.
What is Loopy Pro? — Loopy Pro is a powerful, flexible, and intuitive live looper, sampler, clip launcher and DAW for iPhone and iPad. At its core, it allows you to record and layer sounds in real-time to create complex musical arrangements. But it doesn’t stop there—Loopy Pro offers advanced tools to customize your workflow, build dynamic performance setups, and create a seamless connection between instruments, effects, and external gear.
Use it for live looping, sequencing, arranging, mixing, and much more. Whether you're a live performer, a producer, or just experimenting with sound, Loopy Pro helps you take control of your creative process.
Download on the App StoreLoopy Pro is your all-in-one musical toolkit. Try it for free today.
MIDI Mapping - and why everything is off by an octave
I keep running into iPadOS apps that seem to map MIDI notes differently, always an Octave off from what I expect. This issue has driven me nuts for a couple of years, and I never understood why it keeps happening. I’ve even seen YouTube channels like Sound For More and The Sound Test Room observe this and they just acknowledge it and move on.
I decided to drill down into this and figure out what the f**k is going on. The first thing I noticed is that when I found MIDI notes charts at various places on the web that they seem to be inconsistent as to how things are mapped. Sometimes C3 is outputting note 48, sometimes it’s sending 60. On
apps with keyboards that show both the note name and the MIDI number, (like the built-in keyboard in AUM) you can see exactly how things are mapped. Likewise, some apps that receive MIDI input show both the MIDI number and the note/octave (DigiStix 2 a good example). But sometimes you only have the note/octave to work with (e.g. Beat Scholar). A MIDI monitor is handy to see what is really getting passed around for those. (Stand-alone I like Protokol, and for an AUV3 plugin I’ve been using MIDISpy).
The bottom line is that there are two standards for mapping note/octave to MIDI notes. The good news is that MIDI note values always range from 0-127, and “Middle C” is always mapped to note 60. The “standards” vary only in how they map the note/octave name to those values. I discovered the explanation for this on the Vanderbilt University website, and included that explanation and a link to it in the attached MIDI notes chart, and included it here:
The most common MIDI note mapping designates MIDDLE C (note #60) as C3 (C in the 3rd octave). However, another convention was adopted by Yamaha Corp. for their synthesizer products which parallels the Octave Designation System used in Music Education formulated by the Acoustical Society of America. In that convention, Middle C is designated "C4". The "C3 Convention" is the most commonly used octave designation system on standard MIDI keyboards, but both conventions are in common use. The important constant is that the note range values are 0-127, and “Middle C” is always 60.
I hope this is helpful.
Comments
Actually there are 3 conventions; Xequence Keys uses C5 as middle C, MIDI note 60.
Also, Beat Scholar uniquely allows you change the convention between C3 and C4, so it tries to satisfy all users.
There is NO standard for octave numbering. The MIDI standard is based on note number. Middle C is note 60.
What octave middle C is , is not part of the standard . Octave numbering disagreements pre-date MIDI.
Middle C as C3 or C4 are the most common — Yamaha and Roland use different numbering. Both are very common.
There is no standard for note octave naming. That omission goes back to the original MIDi spec. As @uncledave mentions, there are at least 3 conventions. It's nice when thoughtful developers include an offset setting, but it's also one of those things it's easier just to get used to.
Thanks for the additional comments. The bottom line is, as @espiegel123 points out, the important bit is the MIDI notes number (Middle “C” = 60) but the assignment of octaves has no single standard, so relying note/octave designations can be problematic. As @wim says, it’s just something we need to be aware of and deal with.
@uncledave I didn’t know about that feature in Beat Scholar. Right now I’m having serious trouble getting it to work as an AU since the most recent update. Too bad, as it’s my favorite rhythm tool. I’ll use others for the drum kits, but Beat Scholar is great for those of us that have been formally trained on drums as it carries over the idea of beat sub-division.
It's a feature of the new (free) Beat Scholar Mobile, which apparently replaces the original app. Check the thread on the app, where this was discussed. Not sure if the original Beat Scholar iOS app has this. It's in MIDI Display in the preset menu, long press on the preset name near the top.
From a programmer perspective, midi note 60 would be C5 because you can then derive the pitch class and octave number with modulo and division operations.
Eg
60 % 12 gives us pitch class 0 (c)
61 % 12 is pitch class 1 (c#)
Etc
60 / 12 = octave 5
61 / 12 = octave 5
Etc.
(we’re doing integer division so no decimals)
FWIW, octave numbering on keyboards pre-dates MIDI and was a pedagogic tool to help students identify middle C by counting up from the lowest C on their keyboard. On a standard 88-key keyboard, middle C is the fourth C hence C4. Many keyboards had fewer octaves and middle C was the third C (C3). That is why they are the most common octave designations.
I meant to say “ideally, from a programmer perspective” and that’s just cause the math is easy!
But convention of course is a different thing…., One of the many places where music practice and the math don’t line up perfectly!
Thanks. Found it! And I deleted and re-installed the app so it’s working again…
Excellent point!
I would have said, if we have 128 possible notes and the lowest note is a C, that should be C0. This C-1 / C-2 junk is dumb.
With C0 being 16.35Hz (with A440 tuning) we'd miss the super lower frequencies while still keeping things 'in tune' so here the C -1 and C -2 actually do make sense
Since the point of octave numbering was to help people find middle C on their keyboard, I think that if there were to be an octave numbering convention, C0 would be middle C with negative numbers being octaves below middle C and positive numbers the octaves above.
That's great idea! really... not being snarky... it makes unambiguous sense!
Let's do it in Loopy Pro! As someone once said , standards are great, everyone should have one of their own.... make it an option of course (sigh...)
I actually kind of like the negatives. It helps me mentally keep track of if I’m higher or lower than “Middle C”.
I see your point, but there is some utility to designating the notes in a negative octave range; those are outside the playable range of any instruments and can safely substitute in some applications for CC messages. I use those in Iconica Sketch to switch articulations and to select different patterns and to launch instances in Atom2. Doesn’t preclude doing this, of course, but it’s nice to know where the “extra” notes are.