Three Hums, the last link in the chain, tying yours down! Firsthand experiences combined with anecdotal clues have lead to scientific measurement. Most modern Hums are type 3 i.e. electricity transmission network related. By Dr C. Barnes, Bangor Scientific Consultants. Email scienceconsultants@yahoo.co.uk

Abstract

The Hum is defined and after considering its history, some common cases are briefly reviewed. First hand reports are now being taken from individuals outside the author’s family and not living in the author’s home county. One individual experiences maximisation of the Hum when parked immediately underneath super-grid conductors adjacent to a High Pressure Gas main in addition to within her home in the Wye Valley. This is a classic Hum type 3 experience. A review of Hums past and present suggests that the original Taos Hum, most Hums recently reported in the UK and even the Zug Island Hum may be type 3. It appears that in locations with type 3 Hum the background AC magnetic field is pulsatile. A possible cause of this is power system harmonics, sub –harmonics and inter-harmonics all known to be worse close to wind generation or in industrial areas. The author has developed a powerful armoury for investigation here and hopes to report further in the near future.

Introduction

The Hum is a generic term for an annoying, often nocturnal, noise which occurs sporadically around the World and is only heard by a small percentage of the populous and not easily, if at all, audio recorded.

Early Hums, the so called ‘Hummadruz’ date back to the industrial revolution and were said to sound like a distant swarm of bees usually at dawn or dusk and thus are very probably ascribable to atmospherically propagated factory noise (ref). Scientists at Southampton University have advocated the same simple explanation for today’s Hum, let us call this Hum type 1, the boring one! Quite frankly, in the view of the present author, if this is all there was to the Hum more and more cases could and would be solved using acoustic and infrasonic ray tracing methods.

Hum type 2 amounts to something somewhat similar to type 1 only of more local origin and usually lower in frequency. Hum types 2 are the most easiest to trace. It is estimated by the present author that between 16-30% of all Hum cases are probably type 2 in origin. A good example is the was the called Kokomo Hum wherein audio signals at 36 Hz for a cooling tower were beating with infrasonic signals at 10 Hz from two compressors. This would lead to a Hum with a more pulsatile sound and that of the classic idling engine often described today and often not easily screened by traditional ear plugs. Hum type 2 falls more into the realm of Low Frequency Noise and there are other examples in Journals such as Journal of Noise and Health.

Hum type 3 aligns itself with the formerly more mysterious. Perhaps the original Taos Hum is a Hum type 3. Hum type 3 have been particularly characterised by their apparent lack of traceability and recordability Over the years the present author has shown Hum type 3 to be not that mysterious after all. In that their sources haven’t been traced, it is probable that the recent manifold outbreaks of Hum in the UK and Ireland over the last six or so years to 2012 appear to be Hum type 3. Firsthand experiences of the author combined with anecdotal clues from other hearers and the report of an environmental Health Officer in Sudbury UK (personal telephone communication) have lead to more accurate scientific measurement which confirms definite involvement of the UK power grid and possibly also the High Pressure Gas Distribution System. Interestingly amateur Hum investigator John Dawes has cited involvement of the power grid since the 1970’s originally with an electro-gravitational theory. More recently Dawes appears to have come round to the author’s way of thinking that under certain conditions a space physics connection, depending on the positions of the ionosphere D-layer and possibly Sporadic E may be important for the enhanced perception of Hum Type 3. Further the author is convinced that Hum type 3 as distinct from types 1 and 2 is a magneto-acoustic phenomenon.

This does not detract from the fact that the prime mover is anthropogenic.

Evidence for Power Grid and possibly Gas

In addition to the many recent internet publications of the present author which have been based almost exclusively around his own personal experience and anecdotal reports from his Hum hearing wife, son and sister-in-law, the present author now has access to a lady Hum hearer who is a resident of the Wye Valley in Wales UK. Just like the author and his wife, the aforesaid lady also hears the Hum and perceives it to maximise in a parked vehicle under power lines which are simultaneously adjacent to High Pressure Gas Mains. It is highly instructive to make a comparison of a number of World Hums, figure1.

WORLD HUMS AND SUSPECTED CAUSES
Date	Location	Cause +/or frequencies if known	Hypothetical cause - not proven
All	Hawaii	Volcanic Action
1970's	UK (General)	?	Gas mains and traffic - Fox New Scientist
1990'S	Taos USA	?	Hi pressure Gas/ Hi AC magnetic fields
1990'S	Kokomo	Industrial 36 Hz + 10Hz not all stopped-3 causes?	Industrial area noise + power grid harmonics
1970's	Bristol UK	?	Idling Trains / Suspension Bridges/Electricity Harmonics
1970's	Largs Scotland	?	Ferries/ Trains/Pumped Storage Hydro
2000's	North Shore NZ	56 Hz also 33 Hz component
2004 -now	Bangor Wales UK	Sometimes has magnetic 'comb' component	Pumped Storage/ Electricity grid /Gas mains/Wind farms
2006	Minffordd Wales	? Near supergrid/ near Pumped storage	Electricity Grid/ Pumped Storage
2008	Loch Ness		Pumped storage/wind farms
2008	Sudbury UK	Dissappeared after supergrid and gas main replaced
2009	Bondi Australia		Sewage Plant
2010	Llanidloes Wales	Extension on wind farm	Noise/Electricity harmonics
2011	Woodlands uk	Started after road collapse went away after publicity	Changes in under road service pipes
2011	Windsor Canada	Detroit Zug Island Steel Industry	Noise/Electricity harmonics
Mar-12	Kerry Eire	?	High pressure Gas /Fracking/Seismic Survey
Apr-12	Wye Valley Wales	?	Hi pressure Gas/Electricity Grid
Apr-12	Llandindrod Wells		Wind farms/Electricity Grid
Apr-12	Nr Haverford Wales	?	Hi pressure Gas/Electricity Grid

Figure 1

From the above table most relevant to type 3 Hum is Sudbury UK which happened in 2008.

A first hand personal communication form the then environmental Health Officer to the author confirmed that when a section of 132KV circuit was replaced together with an old gas main, Hum reports from the

vicinity ceased.

The present author has previously made measurements showing just how very subtle changes in the low frequency acoustic and magnetic spectra radically alter Hum perception for him and his family. This is particularly with regard to harmonic, sub-harmonic and inter-harmonic components of the power grid, some of which are pulsatile and these spectra have been published elsewhere. The author has also previously reported on the effect of 50 Hz magnetic field strength under power lines using a home constructed field meter. The sense circuits of this field meter were tuned to 50 Hz and it generally produced a stable output i.e. not able to confirm association with the aforementioned pulsatile spectra.

New measurements

Recent new measurements ( 24^th /25^th May 2012 ) have been made in and around the author’s house and under a section of super grid at Cyttir Lane Bangor using a Cornet ED75 field meter which is magnetic field capable from 1-600mG 50 Hz-15 KHz and RF capable form .1-8GHz.

In all cases the magnetic field is seen to pulsate in a pseudo-random manner by at least +/- 30% in value and sometimes by as much as +/- 50% in value. The pulsation appears to have a slow component between 0.5 and 2 Hz and a faster component that it is just about possible to estimate by eye i.e. about 30 Hz (ref). The pulsation is evident both in the author’s house and under the super- grid. This is highly striking and relevant as such frequencies appear in Hum spectra previously recorded. Some have said the Hum is due to RF. In actual fact RF levels were seen to minimize when the Hum maximized. This may just be coincidence or there may be something more to it. Further investigation is planned to take place. The results are shown in figure 2 below:

Time /Location

Mag field uT

RF Field mW/m^2

Bangor (Home) 7 pm

.05-.1

0.004-0.008

Bangor (Home) 7 am

0.05-.1

0.0007

Power Lines 8.30am

.5+/-.3

0.0077

Figure 2.

Discussion

The results raise important conclusions for both the Hum and power systems stability. Power systems are

meant to have THD of no more than 5% but clearly in terms of magnetic field something strange is

happening. Since type 3 Hummers are sensitive to magnetic components as well as noise ( personal

experience and personal communication) this is not good news and possibly more than any other single

cause could account for all or most of the new UK Hum and Irish cases. Interestingly Ireland has not long

gone on a DC interconnector with the UK. Another recent place with the Hum is Windsor, Canada and

their Hum has been ascribed by some as tentatively Hum type 1 arising from Detroit’s’ Zug Island which

has oil refineries and steel mills. However, metal smelting is notorious for introducing harmonic, sub

harmonic and inter harmonic into the mains because of heavy current thyristor systems and arc furnaces.

The hypothesis here is that Windsor Hum may be as much type 3 as type 1 and this might account for why

its EXACT location has not yet been traced.

Further Work

It is now imperative that the magnetic work is repeated at sites which do not suffer the Hum. It is hoped to report on this in the very near future. It would seem at least for type 3 Hums, the connection with the power grid is now fully sewn up as per Dawes original suspicion. The jury remains out on gas main contributions but in addition to generating their own LFN just as power lines, they will act as long under- earth antennas and by electromagnetic induction the voltages they acquire contribute to seismo- electroacoustic effects.