I was editing a new Dorico score I made for brass and organ and decided to “play around” in the Play tab. I switched from Halion SE to Symphonic Orchestra in the default VST Instrument panel and got no sound–so I switched back to Halion SE, and still no sound. So then I started a new project with only one trumpet and got the usual trumpet sound on playback. But when I switched back to my original project it only showed one trumpet in Play but no sound. After more playing around (not knowing at all what I was doing) I got some weird string-like sounds from outer space. At this point I have no idea how to get back to the origninal brass and organ sounds for my project. I seem to have put that project into a strange state. I’d appreciate some help from the experts. I suppose (ie, I hope) I can get back to normal by setting up a new project and copying the written music into it (haven’t tried that yet), but I’d like to learn how to repair the damage, if its possible. (And what might I have done wrong to cause this playback mess? 
)
–N
You don’t need to switch to “symphonic orchestra”. That is just the name of the bundled sample library you get with Dorico (I don’t know why it even appears in that menu, unless it is relevant if you have bought some additional sample libraries that work with Halion).
You should have all the sample content available in Halion, if you search for the sounds you want and load them manually.
Have you tried going to Play mode, then “apply default playback template” in the Play menu? That should get you back to something that works, even if it’s not the sound you want.
To change a sound, open the Halion window (click the icon that looks a bit like an “e”), click the arrow at the right of the sound name in the "multi program rack, " and type something in the “search results” box if the list of sounds is too long or doesn’t seem to contain what you are looking for.
IIRC there is a buglet - editing the sounds etc only works “properly” (in the sense that Dorico remembers the changes) AFTER you have played something in the score. Starting and stopping playback before editing the sounds, even if you can’t hear anything with the current mess, might help.
Rob,
"…[in] Play mode, “apply default playback template” "
That worked! Whew! Thanks alot.
–N
P.S. I’ll await fullsome documentation on Play mode before “playing around” with it anymore.
P.P.S. In the mixer (F3), the far right entry, Reverb, doesn’t seem to do anything that I can hear, even at maximum setting.
Make sure that you have a reverb plug-in loaded into one of the inserts on the FX channel. By default Dorico loads REVerence in there, which is the convolution reverb that comes with Dorico, and you should find that it makes a difference to the sound. You can choose how much signal to send to the FX channel via the little horizontal slider controls directly above each main channel fader.