This is an old post, but I'm browsing and I see this question come up over and over without a totally clear answer, so I'm gonna leave a comment for the benefit of anyone who happens to be reading here as they try to figure out the ESX-1 they just purchased. This is the final draft of this comment. I deleted the original when I found some grammar issues and some points that needed to be clarified. You might delete the original reply to that so the original text (quoted in the reply) is no longer on the board.
The way the files saved to SmartMedia or SD card in the Electribes (both the ESX-1 and the EMX-1, but not the earlier ones) work is this: Each saved file includes every setting in the machine except for hardwired knobs like the volume and tube gain. This means that on the ESX-1, in each file you load or save when doing a "load all" or "save all," you are loading or saving three things: samples, patterns and songs. On the EMX-1, you're only saving patterns and songs because the samples are static. On both machines you can also load and save individual (rather than all) patterns from/to the card. With the ESX-1, you can also do individual loads/saves with samples. On neither machine can you load/save individual songs. To load or save songs you have to "load all" or "save all."
The structure of the loaded samples, patterns and songs is this: First, inside the Electribe you will find sound files called "samples." They reside in internal memory and are available for use in all patterns. You can hear each one by selecting a pattern and loading the sample into a part (parts are associated with a drum, keyboard, stretch, or slice button) and pushing the corresponding button (or in the case of synth parts, first the button then a keyboard key). The playback will reflect the sample audio data, processed with the filters, modulation and effects present on the part. Next, patterns are files which contain sequencing and settings data for how the Electribe plays back the samples when the pattern is being run (played). These settings are stored in individual parts within the pattern. Making changes in a pattern part (i.e., with the filters, modulation and effects) does not change the data in a sample because pattern parts are not sound data, but rather MIDI data which includes instructions on everything from how quickly to play, to when to make settings adjustments. Two (or 256) different patterns may use some or all of the same samples, and they may sound dramatically different because they have different settings in the modulation, filtering and, of course, sequencing data in different parts which might use the same sample. It's even possible to use the same sample on multiple parts within a single pattern and get a different sound for each part by tweaking the aforementioned settings to different values. Last, songs are built out of patterns which have been strung together, and also contain performance data, which means that you can adjust the settings and muting of the parts as you record them in song mode and they can be replayed, in song mode, with these changes in effect. It then sounds as if you're making the same adjustments again as it plays. Making song changes in this way does not affect the data in the pattern, nor, of course, the data in the sample.
I don't know that much about other grooveboxes, but it sounds like the other dominant paradigm is having different "kits" and then having patterns based on those. You can probably load different kits from a disk or over MIDI, and it changes the patterns and the sound (samples or synthesis settings) in the board. Here we have the difference between the Electribe boards and those other boards: Electribes are designed to use the Save and Load functions to make backups and to make mass changes in the contents of the entire machine, including samples, patterns and songs. To accomplish the same change for which you would typically use a Load command on these other grooveboxes and/or drum machines, on the Electribe you instead simply change patterns or songs because the sample library stored within the Electribe sample bank at any given time is large enough that you can have several "kits" available at once. The advantage is that the sounds from all "kits" are available to all patterns, and of course, it's quicker to change. However, the only samples available for immediate playback and use (without a reload) are those saved in the internal memory. The Smart Media/SD card's contents are not accessible to patterns without loading, and this can't happen on the fly; they only come into play with the "memory card" functions. If you sample library is larger than the maximum amount of memory in the Electribe, you'll have to maintain multiple backup files to contain it.
This is sort of limiting in a few ways. For instance, suppose you do run out of space in the internal sample library at a certain point and branch off with a new backup file for the Electribe. You develop a new library of samples, patterns and songs, and now you have two distinct sets of these. Now suppose that you want to take some samples from the first set (we'll call it Set A) and put them in with some samples from what we'll call Set B. On the EMX-1 (the blue one), this is a moot point. There is no difference between the samples in the two saves because the saved files on the EMX-1 do not contain sample data in the first place; they only contain sequencing data for patterns and songs because this unit is designed to keep its samples constant. There's no way to change samples on the blue EMX-1 at all (not yet and probably not ever).
However, on the ESX-1, using the system Korg has given us, the way to get samples from one set to another is to load individual samples and patterns from the save file (on the card) containing Set A while you have Set B loaded. If you're out of space in Set B, you'll have to delete some samples from Set B before you can load more (make sure you back up Set B before deleting or loading anything!). Say you want 50 samples from Set A; this process of individually moving them over requires a lot of knob twisting and button pushing, the disadvantage of which is in no small part the risk of mistakes as you get bored doing the same thing over and over again. If you do 50 samples like this, you probably will make a mistake. Here's where we have the big advantage offered by the app which is the subject of this Wiki. OpenElectribe allows you to open the save files from the ESX-1 on a proper computer and do some of those simple swapping functions using a mouse instead of a knob. Also, it will allow you to import sound files instead of having to record through the ESX-1's onboard audio inputs (no small advantage!). In the process, it also grants you the ability to craft your samples in a proper DAW (a frickin huge advantage). Overall, this is the program Korg should have given ESX-1 owners when they released these boards, as it makes the Electribe a useful piece of gear rather than a beautiful machine with a seriously under-realized methodology. Go Jeff!
Hope this clears it up for anyone looking. If someone spots a mistake in this post, please let me know!