Hi, Luca, I have listened to your recording of the Hum: It is great that you managed to record exactly what I hear when the Hum is present! I mean, the Hum itself sounds different, but there is always that "brown noise" which comes with the Hum in Hum contaminated places and I cannot mistake it. Your recording is amazing.
I wiill try to find some spare time to read your research. Meanwhile, if you feel interested in my own Hum recordings, please feel free to contact me. They are quite interesting... Have you been able to read Victor Nixon's findings on this forum? He sadly passed away last year and I believe that the Hum killed him. An electrical engineer, a very good neighbour in my new residence, has suggested that the Hum may be caused by the rectifiers which are used to transform the AC to DC (he said that they always have a lot of problems with them and the harmonics etc. they create). AC to DC is always used when there are electronics on the power lines! He also said that actually it was in Britain, in 1960s, when the "powerelectronics" has taken off (and when the Hum has started)... I am not only hearing the Hum but experience terrible body vibrations (and in my feet, constantly). I have always felt vibrations (since the Hum invaded my life) when I stand near CCTV cameras and security systems for remote control, also near the electronic tills for cash payments, next to cash points - where also DC is being used instead of AC.... This is worth exploring... Best Regards, Lidia 11 юни 2013, вторник, 13:18:31 UTC+1, Luca Rizzardi написа: > > Hi Trev. > I suggest you to use a pair of good headphones or a subwoofer. > I'm not sure I understand what you asked me: If you mean a spectrum peaks > analysis, here it is: > > > <https://lh5.googleusercontent.com/-MfBAFd2x0Og/UbcUeVLU-mI/AAAAAAAAAQ8/K_W_F60vTb0/s1600/Schermata+2013-06-11+a+01.34.54.png> > In the peaks, the signal at 30 Hz reaches levels of about 59 dB SPL, which > is conventionally just below the threshold of audibility, meaning that an > individual with an average sensitivity will not be able to perceive it, > while someone with a sensitivity even lightly above the media, in favorable > conditions, could hear it. > The spectrogram instead you can see it on the youtube video I linked! > > The instrumentation I used is of excellent quality: professional low-noise > Schoeps and Sennheiser microphones that go down very low in frequency and a > professional TASCAM digital recorder with battery operation to avoid direct > induction from the power supply (the signals at 100 and 200 hz are radio > signals from the mains). > The home owner, a hummer, could hear the hum during recording, I don't. > Sorry but my English is at school level, I don't speak it very well...I > hope I understand what you meant. otherwise re-explain it :) > > Thank you > > Luca > > Il giorno lunedì 10 giugno 2013 15:06:58 UTC+2, Trev ha scritto: >> >> Interesting work Luca.. >> I have to be honest and say it doesn't sound like my hum. Quite a low >> level to get through my PC speakers maybe didn't help. >> Did you get a harmonic frequency analysis at the same time- ie:spectral >> spot freq peaks? >> What I did pick up was a wider band, less pointed steady hum, than mine. >> I know that your measuring gear could be getting part of the story, >> though- Hum is notoriously difficult to nail. >> ie: It could be co-incidental hum related noise at your location. >> The big ?? is- was human hum pick-up detected at the same time and with >> similar modulation? >> Regards Trev >> >> >> On Friday, 7 June 2013 00:48:10 UTC+1, Luca Rizzardi wrote: >> >>> Hello. >>> I'm Luca, a sound engineer from Italy. >>> I am not a hummer, but I spent the last 9 months studying The Hum, with >>> the assistance of my university advisor and two hummers of the area. >>> I studied a lot of the theories and publications about the phenomenon >>> (in particular those of Chris Barnes and Tom Moir), analyzed testimonies >>> and data from different forums like this and The World Hum Map and >>> Database, studied the behavior of the phenomenon and formulated >>> my hypothesis. >>> Finally I have successfully recorded The Hum. >>> >>> On this link <http://www.youtube.com/watch?v=MhNCdzA6Fmc> you can >>> listen to my recording and see the spectrogram. >>> Frequency of the noise is around 30 Hz. >>> >>> This is my >>> thesis<http://www.scribd.com/doc/144697878/Luca-Rizzardi-Conservatorio-C-pollini-Padova-The-Hum>, >>> >>> unfortunately in Italian language. >>> I would be happy to exchange some opinions with you. >>> >>> Luca Rizzardi >>> >>> >>> >>> >>> -- You received this message because you are subscribed to the Google Groups "Hum Sufferers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/hum-sufferers?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
