(ricercare, (Italian: “to seek out”) musical composition for instruments in which one or more themes are developed through melodic imitation;)

Bach used this term to describe two pieces from ‘The Musical Offering’, one of which is the fugue we are performing tonight.

A fugue is a musical form of which Bach is the undisputed master. It consists of a single theme which is introduced again and again, each time by a different voice. So a four part fugue would have an initial statement of the theme, with three further entrances following sequentially. (In this fugue, there are six voices, so six entries in the first episode)

As each new voice enters, the previous voice continues with a counter-theme, which with Bach always flows seamlessly onwards, complementing the new entry of the next voice perfectly.

These blocks of entries or ‘episodes’ as they are called are the fenceposts of the fugal structure. Linking them are ‘Interludes’, music usually made up of small motives from the main theme. The interludes can be very different from each other in texture and atmosphere, and this fugue is particularly varied in this respect. Imagine that the episodes are home, and the interludes are journeys to another place, each of them with its own unique sonic environment.

A fugue can have any number of episodes and interludes and usually ends with a final statement of the theme by one of the voices.

Listening to a fugue is a unique musical challenge – one is being asked to listen and aurally acknowledge the appearance of the main theme whenever it appears; listen to the counter-theme too; and appreciate the skill with which the different contrapuntal lines are developed and interact with one another as the music progresses.

This is the theme of the Ricercare á 6 fugue – a perfectly balanced musical phrase in every respect.

Fugue theme

You can see from the score above how the chromatic descent from the end of Bar 3 fills up the space created by the first five notes.

And the counter theme which looks like this:

Counter Theme

One wonderful aspect of Bach’s fugues is that you can play them on any instrument whose register fits the part – a string quartet or a church organ, they all work beautifully.

Tonight we are using a full orchestra. The strings carry the body of the fugue, while the woodwinds and brass colour the thematic material, highlighting the themes and thematic fragments that make up the whole.

The following history of the Musical offering is from Wikipedia:

The collection (the works that make up the Musical Offering) has its roots in a meeting between Bach and Frederick II on May 7, 1747. The meeting, taking place at the king's residence in Potsdam, came about because Bach's son Carl Philipp Emanuel was employed there as court musician. Frederick wanted to show the elder Bach a novelty, the fortepiano, which had been invented some years earlier. The king owned several of the experimental instruments being developed by Gottfried Silbermann.[2] During his anticipated visit to Frederick's palace in Potsdam, Bach, who was well known for his skill at improvising, received from Frederick a long and complex musical theme on which to improvise a three-voice fugue. He did so, but Frederick then challenged him to improvise a six-voice fugue on the same theme. Bach answered that he would need to work the score and send it to the king afterwards. He then returned to Leipzig to write out the Thema Regium ("theme of the king").”