It should be mentioned that the Concerto da Camera No. 2 that was posted by Thalbergmad is an arrangement for solo piano. It is not to be learned with the intent of performing it with an orchestra as certain piano parts were changed to better reflect the orchestral parts. The actual solo part is slightly different than this arrangement. I don't know who arranged it that way but it could have been the composer or the publisher who arranged it for initial publishing. (Who, during the 19th century, would have had the privilege to play with an orchestra?)
As to the first chamber concerto, it is also an arrangement for solo piano. But the piano solo part seems to be intact with just additions (in smaller noteheads) for key orchestral parts; the orchestral exposition is in smaller noteheads as well. The orchestral parts would be played if performing the work as a solo piece or omitted if performing with an orchestra.
Also indicated are the "tutti" and the "solo" parts to make it easier to distinguish what is to be played or omitted (if performing with orchestra, of course).
I am looking for the actual solo part of the 2nd chamber concerto but I do not know if it is actually published by Billaudot or any other publisher without having to purchase the open score which would be too expensive.
Topic: Alkan´s Concerto da Camera nos.1-3 for orchestra