At the request of the 8^th Duke who commissioned the organ, the finest possible materials were used to construct the organ. The front pipes offer their silvery shine to a high content of tin (93%). All the pipes on show are fully functional, and those visible at the front of the organ are part of the Great 16’ double diapason tower. One of these pipes on the left hand side of the organ has a dent towards the top, apparently caused by a wayward cricket ball!

Most of the internal pipes are constructed from spotted metal, 50% tin and 50% lead. The magnificent thirty-two foot pipes are made from zinc, and were constructed in-situ, being impossible to transport in one piece.

Inside the organ, wooden pipes are made from Kauric Pine whilst the moving parts such as the swell-box shutters, and bases for the pneumatic levers are made of Honduras Mahogany, at an additional cost in those days of £400. The ivory and inlay work in the console area was created by an Italian company – the notes depicted are back-to-front, possibly the designers "signature" , or maybe just a drafting error.

The Organ Console : Choir, Great, Swell and Solo manuals from the bottom up.

The organ comprises four manuals: Choir, Great, Swell and Solo. The swell organ is enclosed in shutters, allowing the volume to be adjusted by the player. The Solo organ is also enclosed, apart from the Tuba and Gamba stops. The shutters are operated by foot-operated levers adjacent to the pedal board, which require the foot to be hooked under to pull up (and reduce the volume), or pressed from on top to increase the volume.

Perhaps unusually, the Choir organ is not enclosed, and also does not benefit from a swell-choir coupler. The limited number of stops available make this the least-used of the divisions, but the 8’ and 16’ Cor Anglais stops, and the 2’ Piccolo are attractive stops.

The organ solves the touch-sensitive action desired by organists in an interesting way. As electric-action organs emerged in the 20th-century, the ability to control the attack and release of a note was lost. Tracker actions allow direct control by the organist’s finger to the opening and closing of the valve that admits air to the organ pipe (or pallet, as it is known in organ circles). In an organ the size of that at Blenheim Palace, a tracker action would have been very heavy, so Willis devised and patented a “servo-assisted” tracker action.

 

 

The design was patented by Father Willis in 1884, under London Patent 15,114, and the patent diagram is reproduced below.

The majority of the organ operates on a wind pressure of 4" Water Gauge. The pedal reeds however operate at 8" Water Gauge, and the Solo Tuba at 13" Water Gauge. The Solo Tuba pipes are also positioned right at the top of the organ, on the outside, allowing the sound to carry well above the chorus. Trumpet Solos and Voluntaries work well on the organ as a result, and offer an inspiring sound in the library.

Internally the organ layout has the choir organ directly in front of the player, with the Great on top. The Swell organ is enclosed in shutters towards the rear of the instrument. The pedal stops are located above the swell box, with the large 32 foot pipes in a semi-circular arrangement at the rear of the instrument, due to the original location in the bay window of the library.

The Organ Layout

The organ tuning is significantly above concert pitch, making it a challenge when accompanying other instruments, which find it difficult to retune. Middle A on the Blenheim organ is at 450Hz compared with the standard 440Hz – this is 40% of a semitone sharp. A re-tuning exercise would be almost impossible – there are approximately 2300 pipes in the organ.

 

Inside the Organ - some of the 2300 pipes