Blue Box should be used as an educational tool and utility. Blue Box should not be used for any illegal purposes.
Blue Box generates two frequencies in combination to produce a dual tone signal. Do not play these tones at high volumes through head phones, as with any high volume sound it is possible to cause hearing damage.
Since decoding is software based, sampling and evaluating the incoming sound is processor intensive. Blue Box’s performance may differ between devices with different processors.
Tones that are less than 100 ms with pauses that are less than 100 ms are difficult to process in software. Future versions and processors may increase the reliability of faster tone sequences.
If you need touch tone decoding for higher speeds, a hardware solution is recommended.