High bass key
The all natural tuning is also called 'high bass key', which might refer to the pitch FF being
used rather than EE on the 'téad leagaidh' 'string of lowering'. Bunting gives no Gaelic
equivalent for his term 'high bass key' which (perhaps in analog to the relationship between
the terms 'the sisters' and 'na comhlaí') might indicate that it was a indirect translation of
'téad leagaidh'.
However, unlike 'téad leagaidh', 'high bass key' might imply that tuning the string to FF
involves changing from a normative EE pitch, there being no 'low bass key'. As a term
existing solely in English, this might reflect the practice of Bunting's time when 'leithghléas',
which utilised the EE, was the normative tuning on the Gaelic harp.
On the other hand, 'high bass key' might reflect the movement in pitch in the bass when
settings of pieces are transposed by retuning, for example, from G major up to C major. The
term may reflect a practice of raising songs out of their harp vocal range into a higher key
for a purely instrumental performance. Some Carolan songs may have had their vocal
ranges expanded for instrumental purposes in connection with such a technique.
In contrast, the Cardiff MS Havod 3 illustrates that 'is gywair' (low tuning) on the Welsh harp
is 'rightly called the C tuning' but also says that this tuning 'may be as high as one wishes
and as low as the lowest of all', implying G as a kind of middle.
Another possibility is that high bass key, via the FF string is a direct reference to major
modes which had their finals on the note F where those of other modes were on C. The seòl
slinneadh suggests how this may have worked.