Continuo from previous post .
Up to removing old hardened surround impregnation . Entire procedure is already explained here, but I’ll try to illustrate it and explain more thoroughly .
What you need is :
– Alcohol (Etanol) 96%
– cotton rug
– small container for Alcohol
– small brush ; that sort which is bad for any painting , but perfect for purpose – around 10mm wide , plastic threads – so it is semi-hard ….. perfect for applying some force , which we really need here .
And poor old boomer’s surround is looking pretty lousy …… resulting in Fs of ~60Hz .
K3808/K3809 is having 35Hz fresh from Tannoy , somewhere in mid of 1980-ies .
I have strong opinion that every Tannoy driver equipped with impregnated cloth surround is having exactly same issue , if older than 10 years or so …….
Prepare nice stand for spk – be creative 😉 …….. it will stand more firmly and rotate easy .
Then …….. read image captions ….
Alcohol soaking/cleaning swipe steps explained per phases ; in fact – for soaking you need less angles (slightly less wet brush for soaking per Stroke 1 , to avoid leaking alcohol to cone ) but for brushing/cleaning you need them all , always drying a brush between strokes :
Say that 3 times circling around are enough for a day ; in fact , you can do back side of surround (no more than 2 circles for it ) same day :
So – first day – 3 times around for upper side and 2 times around for back side ; from top picture look , to something as shown here :
you can clearly see rubber residue ; not bad for 3 times around
Count on 5 days fun – prepare nice muzak , coffee , (tobacco optional) and after some
(3 + 2)x5 times around , you’ll have drivers ready for applying special ZM Rat Glue mixture 😉
Rat tutorial in next part ….
