Traces of Official Special Surveillance Devices Found in Leaked Recordings

Examination reveals unsuccessful attempt to delete markers from Special Surveillance Devices (SSDs) in leaked recordings
Екип на Биволъ

Repeated sound markers (beeps) in the range 5,8 kHz have been found in the leaked recordings from conversations between two former Bulgarian judges, exposing corruption, lobbying and trading influence in the judiciary, in a case now-known as “Yaneva Gate”. The files have been processed and attempts to delete the markers have been made, but traces of them have remained.

This raises doubts that the recordings have been made with SSDs. The same markers were found by Bivol in other leaked recordings that flared in 2010 another scandal known as “Misho the Beer”.  It was officially proven that these recordings have leaked from official SSDs.

In the “Misho the Beer” recordings, the markers were with a frequency of 2.56 seconds in the range of 3,25 kHz. In the “Yaneva Gate” recordings, the frequency is 5.12 seconds, multiple of 2.56. The range, however, is different – 5,8 kHz, with lower harmonics detected in the range 2,7 kHz.


The markers (beeps) can be heart and visualized very clearly in the spectrogram  at the end of the first recording from Season 1 where there are long pauses and at the end Yaneva says: “I believe I have functional immunity”


The analysis of the recordings shows that they have been transcoded from the compressed format MP3 to AAC, then decoded to WAV files without compression. Filters have been applied as well, and it is quite possible that this was an attempt to delete the markers.

In an earlier article, Bivol wrote that the “beeps” characteristic of recordings made with SSDs could not be heard in the “Yaneva Gate” ones. For comparison, the markers in the recording “Misho the Beer” could be heard with the naked ear. The periodic beeps in the recordings “Yaneva Gate” became apparent after multilevel noise filtering and frequency reinforcement.

With their strict frequency, the markers ensure the authenticity of the recording and lack of editing. Stable tones in the lower part of the spectrum have been detected as well, and they also showed no signs of editing.

Until now the official position, voiced by Prosecutor General Sotir Tsatsarov, was that the recordings have not been made with SSDs, thus they are illegal. The new discovery, however, imposes the imperative to have a full and independent expert probe to investigate the markers and compare them with the official ones, and to make a full and independent review of the use of SSDs in taping the protagonists in the conversations.

Bivol has provided the files and the information on the markers to the Ethics Commission of the Supreme Judicial Council (SJC) – the body in charge of the probe, which turned to our editorial office with an official letter on December 1, requesting these files.


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