How the SPD-SX stores kits, waves and backups

The Roland SPD-SX keeps everything on a card, in a folder layout you can open in a Finder window. Knowing that layout is what turns the two awkward questions into ordinary ones: which file is actually the backup, and why a Mac sometimes refuses to see the card at all.

Sources: the SPD-SX Editor project's own functional documentation, and Roland's SPD-SX Owner's Manual. Facts are cited from both. None of Roland's text is reproduced here. Firmware and models differ, so if your unit's menus disagree with this page, your unit is right.

A project is a folder with three parts

What the hardware calls a project is a folder skeleton on the card, with three directories at the top level:

KIT WAVE SYSTEM

The sample files themselves live one level further down, under WAVE/DATA.

The practical detail is which folder you point a computer at. It is the card’s root, the level that contains those three directories, not one of them. Software that expects a project and is handed the inside of WAVE is being shown a fragment, and a project that appears to be missing its kits is usually a project that was opened one level too deep.

A project holds one hundred kits, and always one hundred

The count is fixed. Roland’s Owner’s Manual states it twice, once in the text introducing what a kit is and again in the specification table, and the SPD-SX Editor project agrees: a newly created empty project is built with one hundred initialized kits already in it.

That is worth internalising, because it changes what organizing a card means. A project is not a container that grows as you add material. It is one hundred slots that all exist from the beginning, most of them empty on a fresh card. The question is never how many kits you are allowed, it is which slot a kit sits in and what is sitting in the ninety-odd you have not looked at.

A .spd backup is an archive, and there are two kinds of them

The .spdfiles the hardware writes are archives. In practice they come in two different flavours: some are ZIP archives and some are tar archives. This is not a distinction between a Roland file and a third-party file either, because Roland’s own factory backup is part of the same picture.

One consequence, and it is the reason this section exists. The extension does not tell you which kind you have. If you rename a .spd and hand it to a tool that only understands one of the two formats, it will work on some backups and fail on others for reasons that look random from the outside. Anything that claims to read .spd files has to handle both.

USB Storage or MIDI, and why a Mac sometimes cannot see the card

The unit has two USB modes and they are mutually exclusive. One cable, one setting, two entirely different things on the other end. The setting is at:

Menu ▸ System ▸ USB Driver

• USB Storage is the mode for moving projects to and from a computer.
• MIDI is the mode for playing and editing live over MIDI.

So when a Mac does not show the card with the SPD-SX plugged in and powered on, this setting is the first thing to check and usually the answer. Nothing is broken, the unit is simply answering a different question than the one the computer is asking.

Older units name the same setting differently. Roland’s Owner’s Manual for the original SPD-SX documents it as USB MODE, with two values: one it names for use with Roland’s own SPD-SX Wave Manager software on a computer, and one it names for USB audio and USB MIDI. It is the same single choice under two different labels, so if your menu shows those, use them.

What the hardware plays

From the specification table in Roland’s Owner’s Manual: the data format is 16-bit linear PCM, as WAV or AIFF, at a 44.1 kHz sampling frequency.

Anything not already in that format has to be converted before it can live on the card, which is why bringing in a modern high-resolution sample is a conversion step rather than a copy.

Every sample carries exactly one of eight tags

The wave tags on the hardware are a fixed set of eight slots, and there is no such thing as an untagged sample: every wave sits in one of the eight, which is why one of them always ends up being the catch-all for whatever did not fit the other seven. The order the slots appear in is the hardware’s own field, not something the naming decides.

This one is documented by the SPD-SX Editor project rather than by the copy of the Owner’s Manual these facts were checked against, so treat it as a fact about the units that project was built and tested against rather than as a claim about every revision of the hardware.

Working on a copy, and what we make

Everything above is true whether or not you use any particular software. A card is a folder, a backup is an archive, and the single most valuable habit is the least technical one: copy the card before you change anything on it, because a project is one hundred slots and there is no undo on a card.

SPD-SX Editor is the Mac app we make for this. It opens either a card root or a .spd backup in both of the flavours described above, and works on it as a project. Nothing on this page needs it.