It’s about emotion. don’t you think? The feelings engendered by my change in tonality sense suggest that what makes keys so special is the emotion they bring. This morning while I was doing early morning things such as watering the lawn and emptying the dishwasher, the Fine Music Radio announcer said that he would be playing the Nocturne from Mendelssohn’s incidental music to A Midsummernight’s Dream. This piece is one that for me epitomises what E major can bring. To me E major is the warmest of the keys – a radiant warmth, with a purring quality. I was all prepared to hear it in the disappointing facile key of F major, being the key one step above E major that my changing brain would bring it to me in. But, no, there was the all the warmth I remembered – I was hearing it in E major. I sat down and enjoyed the French horn solo and the ambient warmth Mendelssohn had written for me. Pleasure restored, joy experienced.

Why did I hear this in E major this time? I presume that the recording being played was marginally flat: the physics of this being that the frequency of the keynote was presumably below some tipping point in my central nervous system which determines whether I hear E or F major.

I recently had an experience where I tried to make use of this putative phenomenon. I am transferring the music on my gramophone records to digital format using a USB turntable and some software. I was putting together a Brahms CD and had a little extra space after transferring his 2nd Piano Concerto in B flat (or is it B?). A little piano music filler seemed appropriate – Julius Katchen playing Brahms’ Waltz in A flat, the most popular, was available on another record. A flat major is a serene, beautiful key, with a hint of strawberry mousse about it. Since I now hear this waltz in A major (my least favourite key) and not in A flat, I thought I’d change the pitch using the Audacity program. I slipped the frequency of the playback down until my brain said the music sounded in A flat, and saved. I burnt both the original and the lowered versions on to the CD.

When I played it back on the CD player later, I was surprised to hear my low frequency version in G major, the key below the A flat major I thought I’d engineered for myself. I seemed to have gone too far in lowering the pitch, yet when making the changes I was hearing the same digital sounds in A flat. Now it sounded very lifeless to me, deprived of its flow and colour low down in G major. Mr Katchen sounded as if he was playing it on the floor. So it is not only about physics and frequency and vibrations. Something else is happening. Could it be my mood (emotion again), or what I have recently listened to that may alter my vulnerable (nay wayward!) sense of pitch? I shall have to experiment some more.