The Arp Schnitger organ in the Martini Church in Groningen is one of the most beautiful and hence most famous organs in the Netherlands. It was therefore thrilling when it was announced that this organ was recorded for a sample set, playable with the virtual organ software Hauptwerk.
Two months ago, december 2019, the sample set was released by Sonus Paradisi (http://www.sonusparadisi.cz/en/organs/netherlands/groningen-st-martini.html). It is a large instrument, 53 stops on three manuals and pedal. Sonus Paradisi also released a free demo, comprising 10 stops of the full sample set.
Immediately after it's release I started playing with and on this demo sample set. Though 10 stops is a bit limited, the demo sample set gives a good impression of the full sample set. And because the demo sample set is a bit limited, there are often not many ways to choose stops for a particular composition. Often there is just one combination that sounds good, perhaps two. And choosing from two possibilities is not too difficult.
As an example, here is a recording I made with this sample set of Christan Geist's prelude "Lofvad vare du Jesu Christ" (in other parts of the worls known as "Gelobet seist du Jesu Christ" or "Praise be to You, Jesus Christ")
The basic principle for this kind of pieces is rather simple. There is a part that is based on the choral melody, and that part gets a stronger combination of stops. There is a part that is the accompaniment, and that part gets a softer registration of stops, as to make the stronger part, or solo, clearly audible. And the pedal part get a not to prominent combination of stops as well. On the demo sample set there are only a few combinations possible. The solo can be played with the Principal 8' of the first manual (Rugwerk), with a combination of the Roerfluit 8 and Nasard 3 of the Rugwerk, with a combination of the Gedackt 8 of the second manual (Hoofdwerk) and the Vox Humana of the third Manual (Bovenwerk), or with, as I did here, the Octaaf 4 of the Bovenwerk, played one octave lower. The Gedacht 8' of the Hoofdwerk is for the acccompaniment and the Subbas 16' (coupled to the Hoofdwerk, something which is not possible on the real organ, by the way).
Easy!
Since last week I have the full sample set at my disposal. And now I can choose without restriction the combination of stops that sounds best to me for this particular piece. And things are not so easy anymore. With the full sample set there is a myriad of ways one can register this composition. The first choice is what family of stops to use for the solo voice: a stop of the principal family, a stop of the flute family, or a stop of the reed family? Or combination of principal and reed or flute and reed? Or even a combination of principal and flute (a combination that in some circles is frowned upon). Suppose I want to use a principal 8 for the solo voice, which one shall I use: the Prestant 8 of the Rugwerk, the Octaav 8 of the Hoofdwerk, or the Prestant 8 of the bovenwerk? Suppose I want to use a reed for the solo voice, shall I than use the Schalmey or the Hautbois of the Rugewrk, the Trompet of the Hoofdwerk or the `Vox Humana of the Bovenwerk? Or even the Basson 16 or the Trompet 16 playd and octave up? No, wait, that last one is impossible because than the solo voicve would go higher than there are pipes on this organ. The same questions are possible for the flute family: shall I use the Roerfluit or the Bourdon of the Rugwerk, the Salicet, Quintadena or Gedackt of the Hoofdwerk, or the Holfluit if the Bovenwerk? And to add further complexity, it is also possible to combine any of the previous mentioned stops with a higher sounding stop like a 4 feet (principal, reed or flute?) stop (sounding and octave higher) or a 3 feet stop (sounding) one and a half octave higher or a 2 feet stop (sounding two octaves higher). Or any of the 4 feet stop, played an octav lower. And then there is also the accompaniment to consider. And the balance between both parts.
Help!!
I finally settled on using the Prestant 8 of the Rugwerk as accompaniment, not as solo. The solo I play with a combination of the Holfluit 8, Nasat 3 and the Vox Humana of the Bovenwerk. In effect a combination of a flute, a principal and a reed. And for the feet Subbas 16 and gedackt 8. And then Geist's composition sounds like this:
Without any restrictions, it should be possible to choose a combination that sounds better than on the demo sample set. Or is it? The octaaf 4 is actually quite good as solo stop. As is the combination in this performance. Which one is the better registration?
One thing is for certain: I like my performance in this recording better than in the other. There is more ease in my playing and the timing is better.
Score: http://partitura.org/index.php/christian-geist-lofvad-vare-du-jesu-christ/