Blues Session Superlow. Covers: Chrom. Diatonic Bluesharp with plastic comb in Superlow tuning. Since 2003 Seydel has been working with tunings far below low D. Unbelievably double low F - that is two octaves below the standard key in F - has now been achieved. This is made with new reed profiles and with soldering up the reeds in the lower notes. A unique customised instrument. What can you do with it? Once you have heard the growling sound of this instrument, you will know. Here you can find the available tunings in major chords, however we can produce all other tuning variations on demand. With this harp we are emphatically the market leader!