Prestant And Octave

[Malcolm Farr]

In some of his larger instruments, Cavaille-Coll included both a Prestant 4' and Octave 4' in the Grand-Orgue. The former was part of the jeux de fond, while the latter was part of the jeux de combinaison.

 

Am I right in thinking that one of the main purposes of this arrangement was, using the ventil arrangement, to enable:-

1. the addition of the Octave (as part of the jeux de combinaison) to the fonds 8' or 16' and 8'; or alternatively

2. the addition of the jeux de combinaison to the fonds 8' and 4' or 16', 8' and 4'?

 

In this way, one would seem to have the greatest possible flexibility at 4' pitch.

 

Regards,

Malcolm F

[Pierre Lauwers]

The jeux de combinaisons are on a heavier wind than the jeux de fonds. Cavaillé-Coll often placed some soft reeds among the jeux de fond, only to provide them with a lower pressure, and reversely, some louder voiced flue stops with the jeux de combinaisons. He saw the organ as a whole, not as we do today one division at a time. The role of this louder octave you may compare with what is to be find in english organs that have:

Octave 4' I

Octave 4' II

 

With the I louder and with a wider scale.

 

Best wishes,

Pierre Lauwers.

[nfortin]

I think it would be uncommon to see Octave I and Octave II stops on a single manual in this country, but it is not uncommon to have both a Principal 4' and an Octave 4' on the great of larger organs. It seems to vary which is the more powerful stop of the two.

[Pierre Lauwers]

Of course the naming is undifferent, the basic principle remains the same. When you have many 8' flues, you need a bit more 4' stops with differing power and tone.

 

Best wishes,

Pierre Lauwers.

[Guest Echo Gamba]

I have sometimes seen a 4' Gemshorn doing duty, presumably, as a smaller Principal on the Great. Once, even, as the ONLY Principal: http://npor.emma.cam.ac.uk/cgi-bin/Rsearch...ec_index=D04993 Anyone know of any others?

[heva]

'Our' Hill organ has a 4' Gemshorn on the swell which in holland could have been named an 'octaaf 4'' (on a secondary manual).

It's quite 'stringy' in the bass and becomes more 'diapason' in the treble.

 

A truly remarkable stop; combined with the 8' oboe, close the box and play big chords - micro-full-swell, or nice to play as an echo stop against the big principal 4, or in the low octave in big chords as a string against the lieblichgedeckt (underpinned by the bourdon16') .....

[bombarde32]

I have sometimes seen a 4' Gemshorn doing duty, presumably, as a smaller Principal on the Great. Once, even, as the ONLY Principal: http://npor.emma.cam.ac.uk/cgi-bin/Rsearch...ec_index=D04993 Anyone know of any others?

 

A Gemshorn can be of better blend especially in a small room, due to the conical pipes absorbing some of the higher overtones. I know of at least one smallish church organ where the main 4' Great Principal is actually a Gemshorn, even though it is not actaully described as such on the drawstop.

 

I have also seen (by many builders, esp. Osmond) the stop 'Gemshorn' which is stringier, and turns out to be a slotted Violin Diapason of sorts, which is, of course, definitely NOT a Gemshorn.