Thanks for extra info Luca, most helpful. I do have a sub woofer -but will listen again.. Trev
On 11 June, 13:18, Luca Rizzardi <[email protected]> wrote: > 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/AAAAAAAAAQ...> > 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-pol...>, > >> unfortunately in Italian language. > >> I would be happy to exchange some opinions with you. > > >> Luca Rizzardi- Hide quoted text - > > - Show quoted text - -- 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. For more options, visit https://groups.google.com/groups/opt_out.
