well, i'll throw my hat in the ring too.
Disco and Northern soul are easily recognisable and distinguishable by the soul fan. Its not a set criteria it's a feeling and mood.
for example tracks such as teddy prendergrass Do me, Sister sledge thinking of you, dina carrol aint no man and DJ genesis Tribute to betty wright are clearly disco records - anyone who cannot see that is blind to musical style and most probarbly tone deaf.
70's tracks such as fantastic johnny c, carstairs, eloise laws are 70's stylee northern soul - they have that angst, that 'feeling' that sound that tugs at your heart as opposed to just making your beer jump on the table.
There are then those which fall somewhere in-between - Harold melvyn where are all my friends, four tops i just cant get you out of my mind, holland dzier - new breed kinda woman. These are those where we think 'is this soulful enough to be called northern or not' in this case i would say yes they are but should be played out in moderation.
The acid test is that if you are going to play a record and you ask yourself 'is this disco' - it is and it shouldnt be allowed near a deck unless you are promoting the night as such.
I really think that most soul fans dont mind what other people like - the only reason that this debate rears its head is that they feel cheated.
Promoters of nights that feature this disco style continue to advertise their nights as 'Northern Soul' when it clearly is not a large part of the time.
I can see why they do this - because if they advertised that they were going to play disco music they wouldnt get anyone in. They wrap it up in the all consuming 'Nothern Soul' strapline knowing that soulies will come to their gig and hoping that it will attract a few that like the disco and will come back.
This is why this debate comes up again and again - Northern soulies feel cheated when they spend their time and money going to a gig advertised as 'Northern Soul Night' only to find that a significant part of the night is taken up with music that even a deaf mute would know is disco.
These poromoters that do this know exactly what they are doing - so they play SOME northern soul, maybe 50% - but that's not what they told the soulies it would be. Playing some lets them continue to fool themselves that they are running a northern soul night when in fact it isnt.
If you want to stop this kind of debate then advertise your gig for what it is. Crossover, Modern, Disco whatever you want to call it. But don't call it Northern Soul.
We advertise our gig as 75% oldies Minimum - that means we will play mostly northern soul with a sprinkling of the 70's, crossover tunes - basically a northern soul night that caters lightly for the modern fans but that advertsises as a northern soul night and is what it says on the tin.
Northern Soul Trading Standards Department