Owning an XpressO Synth

Updated 15 July 2023

I’ve owned a DynaSample XpressO (XO) synthesizer since Febrary 2019 and I’m still learning about it. The developer, Ingo, has been very supportive. It’s a great synth, but it’s complicated, the User Manual is not up-to-date, and the display is not intuitive. I thought that I’d like to document all the items that confused me. It may help others.

I will be adding to this summary as the synth develops, and as I use more features.

So, in no particular order, here goes…


Ingo provides regular updates for the XO program, and the XO-Update_ReadMe.pdf file tells you what has changed. I generally apply all updates, however, I recently learned a hard lesson. I hadn’t done a backup for quite a while, and the latest update had a problem (maybe a download error, I don’t know). Anyway, the update said it had applied itself correctly, but the synth failed on re-boot. The result was a non-working XO. I had to download the full operating system and re-install it (not an easy job). On top of that, I lost all my user presets and instrument settings.

So, the advice is:

  • do a backup of your settings and presets (see Configurations, and Backing Up, below) to an external USB memory stick prior to applying upgrades.
  • If you’re really keen, you can do a full backup of the system (Menu: Util> Complete Internal Drive Backup to USB). You’ll need a 16GB USB3 stick. If you use USB2, it works, but it takes forever.
  • make sure you have the originally-supplied USB stick with the complete system on it, just in case everything else fails. This will have an out-dated system on it, but you can then go through the upgrade process to get it working properly.

Preset Storage

The XO comes with Factory Banks F0-F8 and User Banks U0-U9 of 128 slots each. The Factory banks cannot be changed and contain presets for a large range of instrument sounds. Each of the Factory banks groups similar types of presets (eg Wind instruments for wind controllers, Keyboard instruments for wind controllers, etc), and many of the presets appear multiple times over the various categories. The idea is that you save your favourite factory presets into the User Banks, and and then edit them to meet your taste.

You can change the currently selected bank by pressing the left two buttons together, using the right knob to choose the bank name, and clicking the right knob to select it. You can change the name of your User banks to suit your needs. For instance, I have a “Favourites” bank with presets I use regularly, and a “Busking” bank where the instruments are defaulted to “C” transpose so I can use them with backing tracks.


The various settings of the synth (as opposed to the sound presets) can be saved and loaded. These settings include things like be the way various MIDI instruments are configured, the default volume, the default reverb, etc. There are hundreds of settings. This function is found in the Utilities>Internal Backup. You can save to one of 5 locations (named 1-5).

This function is useful for, say, different gigs you play at, or for different instrument combinations you use.

USB Instruments

USB WARNING: plugging stuff into the front USB ports is fiddly. DON’T force the plug in if it doesn’t go in easily. The surrounding casing is quite a distance from the USB sockets, meaning that you can get a lot of mis-alignment, and it’s possible to damage the socket. The casing is also at an angle to the socket, so it’s easy to think that you have it lined up when you don’t. The best solution is to plug in a short USB “extension” cable so you can see what you are doing. In addition, the casing doesn’t allow for “fat” USB connectors (eg: USB memory sticks).

When you plug in a USB instrument, the XO assigns an input number/letter to it. This can be A, B, C or D. The XO tells you when you plug in the instrument which input it has been assigned to. You can also find out after plugging in by calling up the Midi Monitor (pressing button 3 and 4 together) and playing a few notes. You can then configure settings for that particular instrument by adjusting settings for its input letter. Adjustments that I have found useful are:

  • Global>Create Velocity From Dynamic CC. This allows you to ignore the velocity sent by the instrument, and determine it from the CC value after a certain time delay. This is used for instruments that don’t send good values of velocity (the Aerophone is one)
  • Global>Dynamic Control Selection. This configures the synth’s response to the incoming dynamic (breath pressure).
    • dCC – this is the Continuous Controller number for the input. Usually it is 2, for “breath”
    • crv and ctype- this for configuring the curve applied to the incoming CC values. This is useful for my EWI-USB that has no adjustment to the breath curve – it has only “gain”. The XO manual shows the curves available. I use a single type curve with a -30 crv value. Positive values make the volume less sensitive to light blowing , and negative values make it more sensitive (counter-intuitive). I like to boost the response to light blowing.
    • mult – the % multiplier. This simply applies a % to the overall values of the incoming CC2. This is useful if the instrument doesn’t send the full range of CC2 values. Ingo recommends the Aerophone needs a multiplier around 175%
  • Utilities>USB MIDI Input Offset. This increments the input letter that the XO assigns to USB instruments. A reason for using this is that if you use the DIN MIDI socket (and that is always assigned to input A), and you will want USB devices to be assigned to higher values, so as not to conflict. Whether you need to use this depends on whether you use a DIN input device, and what letters are assigned to your USB instrument(s). For instance, my EWI-USB gets assigned to “C” so it doesn’t conflict, but some of my other devices assign to “A”.


The XO provides the ability to configure the EWI-USB when you plug it in. You can turn on or off the sending of a SysEx message to the instrument to configure it. If you have a EWI-USB you need to check these settings prior to plugging it in for the first time – your settings in the instrument may be overwritten. The on/off setting is located in Utilities>Transmit EWI SysEx at Startup and Reset, and the EWI settings are located in the 4 options following that one. If your EWI-USB is connected, and the “Transmit” is on, any changes you make take effect immediately and are stored in the instrument.

One final note about the EWI-USB: there is a function under Global>Retrigger where the XO tries to fix problems with stuck notes. Make sure it’s turned off with the EWI-USB. When it’s on, you occasionally get no note sounding no mater how hard you blow. It happens when you’re playing at low volume and you re-start a note. As far as I can determine, it’s only an issue with the EWI-USB.


I always realised that I could tune the synth to match other instruments, but never had to do it, until, at a performance one really hot day all the other instruments in a concert band I play with were playing sharp, and the conductor asked me to re-tune. I was insulted! My instrument was beautifully tuned…. So I had to learn quickly – How much do I retune? Here’s a handy hint:

The synth is tuned to 440.0Hz, and that is what is shown on the display when you call up Utilities>Mastertune. The smallest difference in pitch that most people can detect is around 10cents (one tenth of a semitone). At 440Hz that is equivalent to about 2.5Hz. So changing by less than 2.5Hz is a waste of time. Try numbers like 2.5, 5.0, 7.5Hz (10, 20, 30cents). Failing that, just remember that the right-hand knob clicks once per cent, so 10 clicks are 10 cents are 2.5Hz

Reverb, Ambience, Delay

Sometimes you want a quick way to adjust the above settings for everything. This is done by going to Global>Reverb, Global>Ambience, and Global>Delay, as appropriate. You can turn them on/off or adjust the levels/type. Each preset has its own versions of these, but these settings are the overall control.


This function is in Global>Transposition settings, or by pressing buttons 2 and 3 together. I have set Autotranspose to “on”, so what happens is that a preset that has its Autotranspose Interval set to -2 will be automatically transposed to that when it is loaded. If Autotranspose is set “off”, then no transposition is done unless you do it manually. I change the names of the presets so that they include the Autotranspose Interval (e.g. “C Clarinet”).

Editing Presets

Firstly, let me say that I am no expert here. The only times I have done editing of presets is when the sound has annoyed me enough, which hasn’t been often. I thought here I’d mention the most frequent edits I do.

  • Edit>Legato Transition. This controls how one note changes to the next note when played in legato mode – when you slur onto the next note. Refer to the manual for the descriptions of the individual settings. I find that tweaking them individually from min to max gives you a feel for what they do. the adjustments are made immediately, so you can fiddle and test at the same time.
  • Edit>Breath Noise Amount. This controls the background breath noise. Again, refer to the manual for the descriptions of the individual settings. I find that tweaking them individually from min to max gives you a feel for what they do.
  • Edit>Autotranspose Interval. This controls the interval that the pitch of the preset is adjusted if the Autotranspose option is on. If it is set to -2 for a clarinet preset, then when the instrument plays a “C”, a “Bb” will sound. See discussion above about Autotranspose
  • Edit>4 Band Equalizer Settings. I’ve found that the response of my loudspeaker/amp is a factor in how “realistic” a preset sounds. In particular some of the bass response “booms” too much. This feature adjusts the output of the preset in 4 different frequency bands, and I’ve had to reduce the bass frequencies for the presets that cause problems.
  • Edit>Edit Preset name. This enables you to change the name of the preset. This is useful for when you have made a significant change to the preset, such as changing the Autotranspose interval, and you want to differentiate it from other presets.

Playing More Than One Instrument

You can have more than one instrument providing MIDI input to the XO. The XO allows 2 instruments (max number of voices). To separate them you need to program the instruments to different MIDI channels – see your instrument manual to learn how to do that.

Next, you need to configure the XO to link your instruments’ MIDI channels to the presets you want. The main screen on the display shows only the preset that is selected for the current “Edit Channel“. The current edit channel is shown on the bottom right of the main screen. “EC1” means that you have channel 1 selected. To assign a preset, you need to first assign a bank to the channel:

  • Select BnkNo from the menu
  • The screen will show the Edit Channel (left side) and the Bank Number/Description (right side).
  • Adjust the channel and the bank to the ones you want (left knob to switch between channel/bank, right knob to adjust)
  • Click OK (right knob)
  • Repeat this for any other channel

To adjust the preset within the bank you selected for the channel, first you have to set the edit channel. You can get that from the EDIT>Select Edit Channel. Check that the EC value is what you wanted, then choose the preset you want. Repeat this for each channel.

The XO will remember your edit-channel/bank selections for the next power-on, but you will have to re-select the presets for each channel.

Backing Up

You can back up your Settings (eg: breath curves, USB instrument settings, reverb, etc), Chord Maps and User Presets. Backing up to the internal folders is useful if you want to return the XO to a particular state after testing, for example. Backing up to USB is appropriate before doing an upgrade of the software, as it is possible that the disk drive is corrupted, and you will have lost all your user settings (ask me how I know this).

The table below shows the options that are available and where to find them in the menu system:

What to backup/restoreFrom -> toWhere?How?
GLOBAL SETTINGS. This saves or loads all the machine settingsXO -> USB
Util>Save and Load All Global Settings <-> USBSelect either Save/Load/Default
Note that "Default" overwrites all the current settings with defaults
GLOBAL SETTINGS and MAPS. This saves or restores the settings and maps to internal folders in the XO.XO -> internal XO backup folders (one of five)
Internal XO Backup folders (one of five)-> XO
Util>internal Backup all Settings and MapsSelect the backup location or the restore location. Click OK
restore6 to restore9 contain settings for particular instruments (eg EWI)
User Presets and Chord MapsXO -> internal XO backup folders (one of five)
Internal XO Backup folders (one of five)-> XO
Util>Intern.Backup of all Presets&ChordMp BanksSelect the backup location or the restore location. Click OK
User Preset BanksXO Factory -> XO current bank
USB -> XO current bank
XO current bank -> USB
BkCPSelect the option you want - copy internally, from USB, Backup to USB. Click OK.

Update History

  • 15 July 2023 – added note on EWI-USB retrigger
  • 30 Oct 2020 – added Playing More Than One Instrument and Backing Up
  • 28 Oct 2020 – added Updating, expanded USB instruments and EWI-USB
  • 15 Jan 2020 – fixed typos
  • 14 Jan 2020 – Original