Dorico and Vienna Ensemble Pro


Dorico is compatible with Vienna Ensemble Pro (VEP) from VSL. This is a program used to host virtual instruments and effects, and distribute CPU time (if the case) between networked computers. It can also be used on a single computer to get advantage of the added goods to a host program.

  1. No need to reload sounds when switching projects. If working on several pieces based on the same instruments, you can ‘decouple’ VEP from the host, and the virtual instruments and effects are not unloaded and reloaded. Dorico allows for not loading instruments when switching projects, but VEP’s decoupled mode offers an even smoother solution.

  2. VEP lets you save templates. You can then rewire the collected instruments from the host.

  3. VEPs is reported to be particularly efficient with CPU and memory management.

  4. One can start composing without having to first load instruments. Just don’t launch VEP, and only launch Dorico. You will be able to write music without the sounds.

Dorico is compatible with VEP, but probably not yet optimized. I’m experiencing huge VST Audio Engine and VEP CPU loads when used together. There are other issues reported by other fellow composers.

I would personally like if VEP was not considered one of the many possible add-ons, but the fundamental one. A bit like NotePerformer, it is hard to imagine using Dorico without it.



I continue experiencing huge CPU times with Dorico + VEP. Reassigning instruments is particularly problematic, with incredibly long waiting times and high CPU from Dorico and VEP.

Is this something that will being kept under observation, or there is no hope it can be solved? It continues to be my belief that VEP has to be considered an integral part of Dorico.



We certainly don’t consider VEP an integral part of Dorico. Dorico has plenty of integral parts as it is! But we know that a number of our users use it, and so within reason we are of course motivated to ensure that it works properly.

What specific operation are you referring to when you say “reassigning instruments”?

Daniel, it’s reassuring to know that VEP is not out of consideration.

In particular, this one:

  1. In Setup mode, open the Player’s box.

  2. Click on the Instrument’s setup dots (…).

  3. Choose the Change Instrument command .

  4. Choose a different Instrument.

At this point, the long wait begins. But it also happen when creating a new player/instrument. And when moving an instrument to a different position, or to a different player.

Here is spindump taken while creating a new player/instrument, with CPU over 600%.



This is pretty fast for me on Windows. With VEP and MIR already open and my standard libraries loaded, changing an instrument from Alto Sax to Tenor only takes a few seconds:

Sorry, I don’t really know how to read that spindump file. What sort of delay times do you get in Dorico’s application.log file?

(You are using 4.2, right? I think this was much slower on 4.0.)

I’m using v4.2 on Mac Mojave.

This is the latest log I find. I’m not sure how to read it.



Yeah, I don’t know how to read that one either. Did you check the application.log file? It looks like it might be at /Library/Users/your-username/Application Support/Steinberg/Dorico 4 on a Mac. Just curious where your times differ from mine.

No, I was sure it was that one! Here is the right one:



96083 ms, yikes!!! Mine was only 356 ms above. You’re getting warnings that the instrument isn’t in the template though, maybe that’s what’s causing the issue.

What might this mean? I’ve a template that tries to include everything. But it is true that I’m editing a file coming from someone else. But I applied my own playback template over it.


My experience with VEP is quite sobering. Dorico has now become so potent that the use of VEP does not actually bring any relevant advantages for me, but rather a number of problems, such as e.g. B. the lost independence and flexibility (I don’t use standard instruments, everything in one file principle), or problems with the memory handling between Dorico and VEP, where some things can go wrong, which you only notice when you reload later…

So I don’t use it anymore, but I have freedom and a clear head and I can always make good use of a few minutes of loading time…

If you edit your Playback Template, are you sure you added your Endpoint Configuration that uses VEP and contains the Oboe d’Amore? If you click Endpoint Configurations and select the one you added, is the Oboe d’Amore actually listed there? I’m guessing somewhere in the chain there’s some disconnect so Dorico can’t actually find it.

Actually, not! My woodwinds endpoint configuration for that library doesn’t include Oboe d’amore. Good catch!


EDIT: Just reviewed my template. Oboe d’amore is there, and correctly routed. Yet, it didn’t appear in the list of instruments, when originally writing this post, after opening the Edit Endpoint Configuration dialog from the Playback Template dialog…

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After adding it, does that bring the time to switch instruments back into the “normal” range?

While it is still high, it’s much better than before. So, I know where to check to see what causing this delay. Thank you!


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