First reports for the Two-Spotted Cricket in the North East of Italy date back to 2003 (see PDF file below).
The first two groups of singing notes refer to Field Cricket, the last two groups refer to Two-Spotted Cricket.
As you can see, in the first part of the waveform, relating to Field Cricket, the initial notes are less wide than the following ones, while in Two-Spotted Cricket they are all more or less of the same amplitude.
Also, Two-Spotted Cricket singing is faster than Field Cricket; this partly reflects reality, as, although depending on temperature and environmental conditions, Two-Spotted generally sings faster than Field Cricket.
The maximum frequency in Two-Spotted Cricket is approximately 600 Hz higher than in Field Cricket (see the above spectrogram).
And now a curiosity: on May 21, 2009, in the mountains of Verona (Monte Baldo), I recorded the song of a Barred Warbler (shown below); in the final part of the song we can see and hear the imitation of a cricket song (Field or Two-Spotted Cricket?), the three final notes, clearly audible in the audio file and clearly visible both in the waveform and in the spectrogram.
If we look for the imitated specie, we could first of all think to a Field Cricket, since this cricket is abundant in the environment where the Barred Warbler was singing; however, since the imitative learning period usually occurs in the first months of life, it is not unlikely that it could be the imitation of Two-Spotted Cricket, since the latter is widespread in the African wintering quarters of Barred Warbler.
This is not a scientific dissertation, but only an extemporaneous thought!