Mellotronists

kenmerb@... wrote:

>  In a message dated 10/14/2003 1:34:10 PM Eastern Daylight Time,
> charel196@... writes:
>
>> I was telling a buddy today about the inner workings of the MK2 and
>> he asked me a question I didn't know the answer to...since there
>> were
>> 2 speakers on each side of the tapes in close proximity to them what
>>
>> kept the magnets of the speakers from erasing the tapes?(even
>> gradually over time)
>
> ________________________Ken Merbler Added : ___________________
>
> This is a good question.  I think it's because the magnets are *at
> least* far enough away from the closest tapes so that they receive no
> damage.  I know that the magnets pose a significant risk to those
> close tapes when changing the tapes.  When I changed mine on MKII
> #247, I was warned about the tendency of loose tapes "diving" to the
> speaker magnet if given a chance, and this does erase them.  So, when
> I changed my tapes, I used a towel and a plastic bowl over the speaker
> magnet on each side, as shown on my web site.  But as far as tape
> erasure from normal use, I would say  that it's not a problem by
> design, although it looks like it would be. Ken M.

_______________________________________________________________

Greetings All,

The MK-I/II speaker magnets are low enough and  distant
enough not to cause any gradual degredation of tapes.
During normal operation ..... If a tape breaks,it will brush past
the magnet and partially erase the tape. LH Tapes 1-4 from
Gordon's ex-MK-I had noticeable drop-outs of audio.
Someone/something wasn't careful.....

The inverse squares law of physics applies to light , electricity,
and magnetism.   Ken M. was taking the proper precautions
during MK-II tape change.  I probably would have unbolted the
Wharfedales to make 100 % sure.

BTW, the JKMK6 has magnets even closer to the bottoms of
the M400 tape-frames within. No problems seen in two years +.
I installed mu-metal (mag. shield) adjacent to the spkrs.
to preclude a future disaster. My pro-active policy of safety.

That's why we 'Tron users cannot stress enough the need to
keep headblocks demagged,non-magnetized hand-tools,
electrical precautions when installing headblock cable,
yada,yada, yada.....

Cheers,  Jerry K.
(MK-I #124, 14,500 lines of flux within Spkr. RS/12/DD model. )